7XM00754 Did a full maintenance before a job, changed oil, trans, hydraulic, both fuel filters, crankcase filter, the air filters were still very clean. Changed oil. I didn't know that there are 2 trans filters, one for steering and one for forward/reverse so I only changed the forward/reverse and not the steering. Inside the trans filter housing were some metal shavings. I forgot to check any screens. Temp is going up to around 200-210. I went and got a laser thermometer, it would say between 190 and 200. Not sure if it would be hotter if I ran it hotter. Symptom is it takes longer to engage in forward or reverse when hot. Steering works fast and strong. Sometimes if I push down hill then stop and try to reverse or even go forward it will not move even with full throttle. This is the only symptom besides higher temp
Also, the wires going to the trans filter sensor are bypassed, connected together. Nothing is connected to the trans filter sensor. Dunno what this would do
Same tractor as your previous thread with the possibility of oil in the radiator. Why start a new thread..? The symptoms you are descrinig could all be related. Have you had an engine oil sample analyzed yet..? If not, why not..? Is your 190-200 engine coolant temp or transmission oil temp..? If it is transmission then the high temp alarm usually sounds about 240, so you are a ways away from that. Did you ever consider reconnecting the filter switch wiring and see what happens..? I would imagine someone else got sick of changing transmission filters because the plugged filter alarm kept sounding (anything to do with the "metal" particles you found maybe..?). Better to find what the problem is and fix it instead of simply disabling the alarm, don't you think..?
Figured they weren't related but now that you say that I feel a little dumb! That's the trans oil temp. There are 2 trans filters right next to each other, one for forward/reverse and one for steering. Steering is consistently 150 degrees. Other is 190-200. Engine and coolant temps are fine. I thought the running temp should be under 190. Good to know it can go up to 240. No alarm ever went off. Oil and coolant samples are sitting next to me now ready to be sent out tomorrow. I will connect the wires and see what happens, also going to get a second trans filter for steering and probably get a sample of both fluids as well. I also remembered when the trans was hotter, I'd be pushing down hill and when I was toward the end I would decelerate and it would fall out of gear and roll forward quickly as if in neutral. So symptoms are falling out of gear when decelerated, longer time to engage in forward or reverse, sometimes when attempting to go in gear on a steeper hill less than 2:1 it would not move but engine would rev full. Hanging on the edge of a cliff playing with tapping brakes until reverse engages sucks! Ha
If you haven't already done so I think you should be adding a transmission oil sample to the ones you have already taken. When you changed the transmission oil and filter you should have also removed and clean the screens. There are two of them. The transmission breather should also have been cleaned at the same time. The two filters next to one another are actually for the power train and the hydraulic system. When you open the cover the filter on your right is the power train (transmission) and the one on your left is for the hydraulic system. (There is also a second filter for the hydraulic system inside the hydraulic tank). Another reason that you really need an O&M Manual. You have a machine that's probably worth close to $100k, how come you don't have a $50 manual, and for that matter how come no $100 Parts Manual either..? What Part Number filters are you using..? There may be a reason why someone disconnected the plugged filter warning on the power train filter and it's related to the type of filter being used.
I will get 3 more kits and send more samples. There are 3 filters over the right fender. One is accessed from the top and is the hydraulic filter. On the side there are the two transmission filters. Cat said one was forward/reverse and the other is steering.. but they also gave me the wrong water/fuel separator filter so who knows. I forgot to check the screens and need to find where they are located. I did not see any screen inside the trans filter housing. I did not know about the trans breather, I asked if there is one but I don't think the person knew what they were doing. Trans filter number 132-8875 or AG26B1. The filter on the machine that I replaced had a different number. I will get it tomorrow.
I have to apologize. The LH filter as you look at it is for the steering system, however it is listed in the Hydraulic Lines group which initially gave me the impression it was part of the hydraulic system. Which in fact it is because there is no separate hydraulic tank for the steering. The correct filter element for that housing is a 132-8875 - more on that below. The O&M Manual would show you the location of the two screens and the breather. Is the $50 for a manual starting to look more & more attractive..? A clue, the screens are nowhere near the filter and neither is the breather. The correct Part Number filter for the transmisison is a 343-4464. There is a Service Article regarding false plugged filter events (the alarm going off in other words) if the 132-8875 element is used in transmission application. Basically the 132-8875 is a quite fine filter relatively-speaking and the restriction it generates in the oil system can cause the filter to bypass and thus set the alarm off in certain circumstances. This may be why someone disconnected the wiring to the bypass switch. Quote - "Contamination is one of the major causes of transmission control system failure. Some power train oil systems used Ultra-High Efficiency UHE filters. The use of these filters frequently caused the oil to bypass the filter [and set the alarm off] . The use of UHE filters in power train oil systems is no longer recommended." (The 132-8875 is a UHE filter) So in summary you have two identical filter housings right next to one another that are supposed to have different Part Numbers of filter elements inside them. Cool or what...? This is the illustration for the hydraulic (steering) lines. This is the illustration for the Power Train (transmission) lines. It doesn't even show the steering filter yet both diagrams are of exactly the same location on the machine........
Awesome info! Sounds like I need to get that other filter and switch it with the UHE then move the UHE to the steering I wonder if that would have any cause on my symptoms
Just wanted to confirm that I need one of both filters? Put the UHE filter on the steering and put the other filter on the transmission? Then I also need the trans breather, check trans screens and take oil samples
Yes. One of each. 132-8875 UHE goes in the steering and 343-4464 goes in the trans. The breather will probably only need cleaning with parts cleaning colvent, brake cleaner, or diesel. (it's metal). Did you get an O&M Manual eventually or do you need the locations of the two screens..?
I was able to locate the screens. I cut the old filter open and it had lots of metallic shavings. When I opened the filter housing to put the proper filter in, there were metal shavings in the housing that was cleaned out 6 operation hours earlier. I cut open the incorrect 6 hour used filter and there was very little in it but there was some stuff that didn't look metallic. Obviously the steering system is very dirty. This time I collected the oil from the housing in a clear bag to see it instead of a black container. I didn't realize how black it is. The dipstick makes it look so clear. I've taken a sample of both the steering and the trans oil and sent it in. I sent in all the metal shavings to CAT premature failure department and they will tell me where the metal is from. When I get a new steering filter tomorrow and replace it, that will let me look for contaminants in the steering system for the first time. It looks like it might be motor oil in the hydraulic system, CAT will let me know. They said motor oil won't hurt the hydraulic system. I will check the screens when I change the trans oil by mid next week sometime. I did reconnect the trans filter sensor and with mid to high rev the light blinks.
The shavings were from the transmission filter housing and not the steering filter, correct..? I know you sadi that you changed al the filters by did you change the oil in either the transmission or the hydraulic system..? (The Cat dealer is correct BTW, engine oil will not hurt a hydraulic system.) It appears that you have found the reason why the trans filter sensor wiring was removed. I'd suggest that you do nothing until you have changed the oil next week. The correct oil for the transmission is an SAE30 that meets Cat TO-4 specification. Don't be tempted to huy parts store brand, use a good quality (major oil company) product, or even use Cat oil if they have any sort of promotion. Often Cat oil is discounted if you buy filters as well and becomes as cheap as anything out there.
Correct, shavings in transmission housing and filter the first time then more shavings in the housing the second time when wrong filter was replaced. I haven't opened the steering yet. I asked for every filter but Cat was having a bad day and didn't know there was a steering filter. I did change the hydraulic filter but not the steering which runs off the hydraulic as well. I did send in a sample of hydraulic and transmission oil Hmm I've been up all night fighting with myself and whether I should take another day off and change the trans oil or work and buy another filter when I change it. I think I will just use the excavator to move the dirt being dropped off in to a pile so they have room to drop off more and spend the rest of the day changing the trans oil on the dozer.
I did not change the hydraulic or trans oil. I will change both
It was recommended that I warm up the trans oil before draining because if it's cold less impurities will come out. Do you agree?
Any oil generally drains better when it is warm, and therefore is more likely to bring out any contamination with the oil when you pull the drain plug. The manual actually states to get the transmission oil warm before draining it. Make sure that you pull the two screens and clean them when you drain the transmission oil (note that there are 2 oil drain points, one on the torque converter housing, the other on the transmission). Take photos of what you find on each one. The reason for saying that is that one screen is for the suction from the torque converter (illustration below) and will be crucial in deciding if the metal you found in the filter housing is coming from the transmission or from the converter. It will be necessary to disconnect a hose to remove each of the screens. Make sure that you have a new O-Ring for each hose, because guaranteed the O-Rings you remove will be flat and hard. You do not want to risk the possibility of creating an air leak on the suction side of the tranmission oil system by re-using the old O-Rings.
I think if you have repeated contamination of the trans filter you better prepare for a complete trans and torque rebuild. I would start by pulling the trans pump. The symptoms you list like loss of trans pressure sound like a failing trans pump. Make sure you do the auxiliary drive gear bearings and rear crank seal while you have the torque converter out.
Loss of trans pressure as in the one time it wouldn't reverse or while I'm decelerating going down hill it falls out of gear and wants to go 100 mph off a cliff? Or both?
The symptoms you describe above could be related to the pump starting to fail and could also possibly explain the presence of the metallic particles you found in the filter housing. HOWEVER, you also say you found non-metallic particles. These could easily be friction material from transmission clutches but without photos of the particles it's difficult to give an opinion. So given the combination of particle types it's highly probable that more than one component in the powertrain is going South at this time. The failure to engage reverse or falling out of gear when decelerating downhill could be related to either a pump problem or low oil level in the transmission . When working on steep sloes you can actually add 10% above the normal specified capacity of oil in the transmission to prevent the possibility of the transmission pump sucking air. Do you know how many hours are on the transmission or torque converter in the tractor, also do you know if ther have ever been overhauled..? I will add one other component to the list - the powertrain oil cooler. If (as seems increasingly likely) you have to go into components like the transmission and the converter as a result of large quantities of particles in the system, it would be false economy not to replace the cooler at the same time, because it will be at minimum partially plugged.
Have you gotten the sample results back yet. I would likely wait to plan out any repairs until I got all the information in. I would hate changing oil and then have to dump it because something inside a component of a system was coming apart.
I was going to send the repair history but it says it's been deleted. I asked them to resend it to me. It has about 32k hours on it. They said it they rebuilt the trans, torque converter, engine and turbo in the last 4k hours. The papers did kinda show that if I remember correctly however I didn't see any history for one of those components, I don't remember which. Honestly I think they're full of crap though. I said before I buy it, repack the front pistons, fix slight leak on the pump of whatever is directly under the seat, change oil, etc. Well the left final drive failed, maybe because it had no magnet but the oil was black. Changed right side oil, black. Trans oil, black. Hydraulic oil, almost black. Front pistons very slight leak. They probably didn't do anything they said they did. Who knows they're just a salesman, the dozer came from a pipe job in Canada.
Results should be back Monday, I'll let you know. The results will be back before oil is changed. Thank you for the heads up!
Back to your post #21 for a moment if I may. I see a transmission & torque converter in the list but no trans pump or powertrain cooler. Hmmmmmmmmm.........
So far Cat said the old filter had some clutch material and also metal. They're seeing what type of metal now. The sos samples are not done yet. The newer incorrect filter that was used for 6 hours did not have metal or clutch material Still working on getting maintenance history
Here is a screenshot of part of the maintenance history
Currently has 4,600 hours
Pictures are of the trans screen. The torque converter screen was missing but there was absolutely no metal or anything inside it when I drained it.
Have to wonder who and why that converter screen was removed????
So there is a powertrain cooler? I had cat do the trans oil change since it was the same cost as me me more to buy the oil and do it myself. I asked them to bring a trans breather and they brought the wrong one (third wrong filter so far from Cat) I asked the tech what is responsible for cooling the trans oil and they didn't know. It looks like a new trans pump was put in 1,000 hours ago
Yes I agree. What a bummer. When I bought it I told them to please fix a small leak under the seat on some part, they said they did and when I was under there today I saw they never fixed it so who knows. I did hire a tech to go over the whole thing before buying and he totally missed the bypassed trans filter alarm, nasty trans oil (just checked dipstick which was misleading) and also missed a broken left final drive. Good learning experience right? At least now I know how to check most everything myself now for future purchases. After changing the oil today I did go down a steep hill to park it and I decided to check if it would fall out of gear while fully decelerating, it did not. It acted perfect. Which leads me to wonder if it just did that because it was 210ish degrees or if because the oil was a little low in the trans.. not sure I'll have to find out when I run it this week. I'm asking cat to come out next week and do another trans oil change and while they're out put a new torque converter screen in and check other filters. Oh by the way, there was some bark and tiny tiny sticks in the transmission when it was drained. Cat told me they had a different dozer that came off a pipeline job that had bark in the transmission, they did a couple oil changes and it works good now. They didn't say it had metal though so mine may be different. A different tech told me those metal chips are normal wear and tear and built up because of the oil not being changed when it should be.
I'd love your opinion on the metal in the screen being usual for a machine weighing 95k pounds and not being maintained properly. All oil was gray and black. No milking or anything. I am going to have the oil drained and filled again next week as well as adding the missing torque converter screen and checking trans pump pressure. Any other things you think I should check?
Screens are always going to catch the odd piece or two of something. That's why they are supposed to be removed, inspected, & cleaned every time the oil in that system is changed. As usual the devil is in the detail - WHAT is in the screen (as in where did it come from - you can usually tell) is just as important as the quantity of material trapped in the screen. The one thing you don't know is how long a time has passed since the one screen that was actually installed in your tractor was removed. That's why a quality maintenance programme is so important, unless you know when that screen was last removed (was it 1 year, 5 yrs, or 10..?) nobody can tell whether what's the material trapped in it is a critical sign of a failure or not. There is actually a categorizing system from 1 to 5 of how to report the contamination found on magnetic plugs & screens. I'll have to see if I can dig it up.
Good to hear from you Nige! Hope all is well. I have no clue but by the looks of everything it has been a long time. Were you able to see the maintenance record? I did confirm the dozer has a trans oil cooler. Is there a way to see if it is failing or not? I'd like to test the trans cooler and trans pump. Then I'll do the oil change in a week and add the torque converter screen. Again, it did not fall out of gear going down hill fully decelerated after the oil change. So far it hasn't seemed weak like when it wouldn't go backwards uphill that one time that freaked me out. Hopefully I caught this in time. I did have the metal in that picture sent to Cat, hopefully they will get it tested soon. So looks like it's another week to two weeks of waiting to see if more metal accumulates. That dozer moves so much dirt so quick so I won't have enough dirt to test the trans temp "issue" until tomorrow or Friday. I'll let you know. I'm still waiting on the sample results I sent in 2 weeks ago for engine oil and coolant. If I find oil in the coolant I will most likely replace the oil cooler since there seems to be a slight engine oil disappearing act which would also be the oil cooler from what I'm told, since there are no leaks
The only way I can think of to get some idea if a transmission cooler is working OK is to take some inlet & outlet temperatures using an infra-red thermometer. From the final drive issues you had before, and now all this, I would say that most of the maintenance work that the seller allegedly committed when you bought the tractor to never got done. So why not give it a birthday..? Oil & filters (the correct ones this time) from one end to the other as a start, maybe do a valve set on the engine as well. I would also have suggested coolant as well but in view of your comments I would hold off on that until it is confirmed that the engine oil cooler needs replacing or not. If the cooler is replaced it would be an idea to change coolant after that and also change the thermostat.
Excellent suggestions! I will check the temp before and after the trans cooler. I agree they didn't do squat, I have replaced everything except coolant (waiting on results),t breather (cat sent the wrong one twice), and hydraulic breather. If you look at the maintenance record, they put a new engine in 1,000 hours ago. What do you think about that? It was done by an actual company, can't remember which one. I've asked them to resend the record because the email says it was deleted on their end so I only have the screenshot. If records say new engine by an actual company 1,000 hours ago would you still recommend a valve set?
Valve set should be done on a new or rebuilt engine when it is first built and also at the time of the first engine oil change, (250 or 500) whenever that is. After that it reverts to the 2000 or 4000 hour intervals as called out in the Maintenance Manual. Regarding your transmission breather (actually "power train oil lines breather") see below - 9G-5127 is the Part Number unless someone has been messing with it.
That picture looks like what cat sent but when they looked at it, it is different. Hmm I wonder Ok I'll check out the valve set
Take a photo of what you actually have installed as a breather on your tractor and post it up. If possible I will try to identify what Part Number it is. I just looked and the Part Number is the same for every 7XM-prefix tractor out there. Maybe someone at the previous owner started getting cute...?
What is this bottom warning light?
Plugged hydraulic oil filter. I thought you had a manual for this tractor..? I seem to remember the subject coming up before.
No I didn't get the manual yet, I'm going to get it now. I thought it was low hydraulic pressure but I'll take a clogged filter any day! I got the filter Friday, I'll get oil and put it on I had issue with the trans filter being bypassed but this is it for warning lights so far So far it's running way better with the trans oil change. Still no results on the sos samples, I'm getting pretty annoyed at that. One of the temperature gauges does still get hotter than I'd like, I'll take a pic. I'll take the pic of the trans breather too
Here's the link again ........... https://catpublications.com/ Put SEBU6891 in the box and hit Search. $46 for a downloadable Adobe pdf version.
I called Cat and asked what's up with the oil samples, it's been a long time. They said they'll call me back. The hydraulic oil was very clean but I got a bypass light on it so I changed it and the filters. I never had an issue with raising the blade but right after changing the hydraulic oil the blade does not want to lift. Neutral high rev it stays down. Forward and reverse it lifts VERY slowly, way to slow to actually work. I checked the manual for a way to bleed air from the hydraulic line and found nothing. I called Cat and they said they self bleed and don't know if a way to manually bleed. Does this sound like air isn't bleeding if it worked perfectly right before the oil change?
First up. What type and viscosity of oil did you use..? Cat filters or "will fit"..? Part Numbers..?
I thought it should be 30wt but I called Cat and they said use 10w30. I asked if 30wt is fine and they said they won't lose their job by saying the wrong thing so use 10w30
I'd have put 10W in it if it was mine, but it shouldn't make any real difference. Did you go with SAE30 eventually..?
I changed it yesterday, it has 10w30 in it. Is this wrong?
It’ll work fine. I was just worried that you may have put 30wt into it. Filters..? Also did you recheck the oil level after you’d run it for a couple of minutes..?
Both filters are new Cat brand. I used the correct model number you sent on a previous post. It was the steering filter not trans
What about re-checking the oil level..? It may pay you to just unscrew the tank cap a little to relieve any pressure and to get the sight glass to read correctly. Just to be sure take the cap right off and look down the hole to make sure you can see oil. Sight glasses have been known to lie..... Any strange noises from the hydraulics..?
I will unscrew the cap to relieve pressure and look inside. It was tilted right when I first looked which had it way full then I went to even ground and it's just above full. I'll be back at the dozer in an hour or two to take the cap off. No noises coming from hydraulics however I was in the cab behind a very loud engine I'll ask someone to pull up on it while I listen
Take a wrench with you and while you're there pull the breaker relief valve off the top of the tank and see if you can a) suck air through it, and b) blow air through it. You should be able to do the first but not the 2nd if it's in good shape. If it looks or tests the least bit suspicious, the Part # is 191-5439. they are supposed to be part of a 2000hr PM, but I'm willing to bet yours has never ever been changed.
Sounds good. I'll look for that part. The tank always has pressure so probably doesn't work
I zoomed in so my personal info isn't there. First one is the engine oil. Second is the coolant
Apparently the tech who took the trans and hydraulic samples as well as the metal shavings from trans screen over a week ago never turned them in. Then the guy in service never scheduled the next trans oil change so I can check for new shavings. They were supposed to come out today. I'll keep you updated. Looks like the coolant and engine is doing well.
The coolant looks OK, did you change it recently or is that what was in the machine when you bought it..? If you haven't changed it then next time ask the dealer to do a Level 2 (complete) analysis on it, the results you have are for a Level 1 (basic) analysis. How many operating hours were on the engine oil that analysis refers to..? Reason I ask is that I can see figures that worry me, even though the dealer analysis comes back with the interpretation that it's OK. This is the problem with analysis of a single sample, the clue is to look for variations over time and a single sample result does not give the information to do that. Also IMHO the lab should put a caveat on all analysis interpretation where the oil hours are not given something like "impossible to give a full interpretation of these results due to unknown oil operating hours". Without the oil hours it would need a crystal ball. The viscosity is slightly on the high side for a 15W/40, should be low 14's - so I look at the soot (ST) which is the number right next to it. 48 equates to 134% on the old soot measurement scale. The number would give me conniptions unless the tractor was working at 10,000ft+ of altitude. I assume the that's not the case with you so the implication from the numbers is that the engine has major combustion problems - incomplete combustion to be exact. Lastly the Lead (Pb) at 5 is much higher than I would like, usually it bounces around between 0 and 1 on a good engine. Here's my thoughts. If that analysis above relates to oil from the previous ownership with unknown (probably high) hours, then go about 200 operating hours and change the engine oil & filter again. Take a sample and see how the analysis turns out. I think we can take it as a given that you were lied to regarding the seller changing all the fluids and filters before you bought the tractor. Last question - do you have to add oil to the engine on a regular basis..? If yes, how much and how often in terms of operating hours..?
Yes the analysis was on fluids from when it was bought. I'll have a level 2 done. Do I need a level 2 on the other fluids? It went to 28.5k hours then the hour meter was replaced and it has 4,500 now. So there is about 4,500 hours between the samples. Yes I was having to add about half a gallon to 3/4 a gallon of oil a day when it was running 10 hours non stop. I have been constantly looking for an oil leak but can't find one. I thought it might be the engine cooler but there's no oil in the coolant apparently which I think there is and the sample or something isn't correct but maybe I'm wrong. It's usually worked around 3,400 altitude.
Also, for the blade not coming up issue, if I put it all the way down I can slowly pull it up with high rev, if I stop half way hen try to go up again, no joy. It worked perfect before the drain and fill of hydraulic oil 10w30 Going to do a pressure test asap. Need to locate where the pressure test is, I assume under the black box on the top front where the hydraulic hoses connect?
As far as hours on actual engine oil, this is unknown. The guy totally lied like you said
No. Only coolant analysis has two levels - 1 & 2. Normally a Level 1 is done every 500-1000 hours and a Level 2 every 2-4000 operating hours. Approximately how many gallons of fuel were you burning in a typical day..? The normal way is to relate how many gallons of fuel are burned for every quart of top-up oil added, provided that the engine has no visible external oil leaks. Testing the implement pressure is not as simple as it is on some machines. The test points are under the floor and you need to remove both the operator seat and the floor panel to access them. See the illustration below. If you want a full procedure send me a PM with your email address.
Roughly 100-110 gallons of fuel a day to 3/4 a gallon of oil
So that works out to approximately 35 gallons of fuel per quart of top-up oil. Anything less than 60 gallons of fuel per quart of oil is classed in the "investigate the cause" part of the chart, so your engine is burning somewhere close to double the amount of oil that it should be per gallon of fuel burned if it was in good shape. The oil is not going into the coolant based on the results of the coolant analysis. So I would guess that the engine is starting to get "tired", and the oil will be going past the piston rings and up the exhaust stack, and the engine is coming towards the point where it will need to be overhauled.
I can suck and blow through the relief valve. Blowing is harder but I can. I did see 3 wires going to the control handle for raising and lowering the blade, they broke off when I touched them. I think this is for the trigger though and nothing to do with raising and lowering the blade. The blade still twists strong. I'll reconnect the wires if I can
The specification of the breaker for opening under pressure is 25psi. Unless you can blow that much (normal humans can blow around 1psi give or take) the breaker valve is foobarbed. I suggest that you replace it.
The relief valve would cause the blade to not go up correct? What do you think about those wires? Probably nothing to do with the blade right?
Can you take photos of the broken wires, or at least give some idea of colours and/or numbers. Every wire has a number marked down the outside of it at about 6" intervals. That will help identify what their function is. The purpose of the relief valve is to create 25psi of pressure in the hydraulic tank so that when the machine is at operating temperature oil is pushed into the implement pump. If the RV is not working as designed the pump has to suck oil, not have oil pushed into it. This will affect pump performance and could potentially affect the speed at which the cylinders move. A new RV is about $150, and your existing one is toast either way. Question: Your problem is that the blade goes up and down more slowly than it should. If you get the blade half-way up and stop, then try to tilt the blade to the left or the right, does the tilt function also work slowly, or does it work at normal speed..?
At all times the ripper and blade tilt work strong and good. Before a drain and fill the blade went up normal and strong. After the drain and fill the blade does not want to go up. If I go up, stop half way then try going up again it fails. To answer your question, if I go up and stop half way the tilt still works perfectly
Here's a picture of the wires on the blade control I don't think they have anything to do with the up and down function
I agree. The end of the bulldozer control handle has been replaced at some time with one that contains the (red) trigger switch used on a machine with dual tilt cylinders to tip the blade forwards and backwards. Your machine does not have dual tilt, or at least it was not built with it. If the blade tilt function is working fine then it would appear as though there are no issues with either the oil level or the oil flow from the pump. I'm now starting to wonder whether when you drained or refilled the oil something that was stuck in a corner somewhere has now moved and is now either blocking something mechanically or hydraulically. First up, does the blade control lever move as far as it's supposed to backwards and forwards (blade up or down), or at least move the same distance as it moved before you changed the oil..?
I was thinking the same thing, I changed the oil and filter because I was getting a new bypass light so maybe it was something lodged in a corner that when drained went to the bottom of the tank just to tease me. The actual control does move forward and backwards as it always has, full motion. I was hoping to have Cat test the flow since they know exactly where to look but it looks like they're going to miss the trans oil change this Friday as well. I called them twice today and they keep saying they'll send another quote and schedule me but haven't yet. They did find the oil samples they misplaced last week so hopefully we'll have a report for the trans and hydraulic fluids as well as metal shavings soon. They did say there is clutch material and metallic shavings, but that's all they can tell me so far.
Got the sos samples back. First picture is hydraulic oil. Second and third are both Trans, maybe they sent the same thing twice
You might want to check the quick drop valves on the top ends of the lift cylinders. I've had one or the other stick open and do what you are describing.
Thanks for the tip! I'll check them out, how would I make sure they're working correctly? I'll try looking on google
Found a lot of info on how they work and such, no info on how to troubleshoot them. Google is saying on the D8R series 2 dozers the quick drop valve is under the black box on the top front of the dozer over the radiator. I've been itching to open it up, maybe it was a sign haha. Just gotta figure out what to do after. More google
The ones I'm familiar with were just a piston assembly in the valve block on the top of the cylinders. When you put full pump flow to drop the blade, the pistons would shift and allow rod oil to flow directly to the piston side of the cylinder and it would gravity feed down. Usually something was broke in the cylinder and stuck in the valve. I think those machines also had the poppet valves in the pistons than would contact the top of bottom of the cylinders and allow oil to bypass around. You might check a part drawing to see what is in the piston, the drop valve and that black box you are talking about.
Maybe this will help. I've seen it before where a lump of something got jammed in the spool of the QD valve, but in that case the blade lift function quit working completely. Remove the tin box over the top of the assembly and start looking under the two covers #9 & #10. Anything that is wrong with it should be pretty obvious.
Oil analysis results. The first result is apparently hydraulic because it states oil viscosity is 10W. However the actually measured viscosity (12.2) is more like a 30 than a 10W. Silicon is high at 15, ISO Code is 22/13 which is relatively-speaking "dirty". If this was the oil that was drained then resample in 250 hours and see how the new oil is performing. The second and third results are in a sense duplicates. One contains the same results that are on the other. Again there is elevated silicon and particle count plus aluminium, iron, etc. No need for immediate panic but you'll have to keep sampling to establish a trend. It could be nothing more than wear caused by the high levels of silicon (dirt). Clean that up and it may be all that's required. It may require more oil & filter changes to get things cleaned up.
I was going to have the trans oil changed again after 30 hours to see if more metal is in the screen and also put the missing torque converter screen on. Is there any reason I should wait for another hundred or two hours before l adding the missing torque screen? The screen is important right?
The screen is fairly coarse and only stops large particles. Usually if there is debris in it something in the torque is failing . In that case you’re into rebuilding pump and torque anyway. I guess you could get starter or gear failure parts in it too.
Yes this is the first oil change since I bought it so unknown when the last time it was changed. When I drained the torque it had no particles but that doesn't mean the particles when downstream somewhere. It would be wise to put the missing screen in so I can change the oil in 250-500 hours and then see if there's new particles in the screen correct? If there's no screen I can't tell if there are particles
I understand where you're going with this, but here's my 2c. The screen should go back into the converter suction as soon as practical, but at the same time I would also be looking at where contamination could be entering the transmission/converter hydraulic system. You remember that we spoke about the breather for the power train system earlier (9G-5127 - Post #36 on Page 2). I would replace that, make sure that locations such as the power train oil filler cap and the dipstick were not letting dirt in, etc. I'd do all that before even thinking about changing the oil again. I would do all the other stuff to make sure that nothing could get into the transmission oil system that shouldn't be there. If you can't keep contamination out what's the point of changing the oil..? I recall that you reconnected the wires on the transmission filter housing. Is it still throwing warnings for plugged filters..? If changing the filter makes the light go out, keep changing them, it means that the filter is pulling contamination out of the system IMHO. For the hydraulic oil I would replace the 191-5439 breaker relief valve on the hydraulic tank (again, dirt can get in there) sample the oil and change the filter every 250 hours, and see how the oil analysis goes. One of the most important factors to consider when you send off oil samples is to make sure that all the necessary information is completed on the form that accompanies the oil sample. Without that info any lab would be struggling to make a good interpretation of the analysis: - 1. Oil changed - Y/N.? 2. Filter changed - Y/N.? 3. Operating Hours on oil..? 4. Approx. quantity of oil added since the last sample was taken.
I understand. When I reconnected the powertrain filter wires it would blink the bypass light at medium to high rev. Then I put in that wrong filter they gave me which would still blink at medium to high rev. I then replaced that filter with the correct filter the next day and it has not given a bypass light since so I guess it isn't that dirty. I'm going to get the picture of the spot for the trans breather today. I think the Cat tech was wrong in saying it looks like something else. I'm going to order the hydraulic valve today as well. There is lots of dirt in the valve. I'm going to buy a fuel gauge for the tank I fill from so I can start keeping track of how many gallons I actually put in each day and how much engine oil I add each day. I know the dozer came from a pipe job in Canada so maybe it was in higher elevation? The next 250 hours will answer a lot of questions with the next sos sample.
Are you talking about the Quick Drop valve on top of the hood..? Post some photos before you go buying a valve. It may be it just needs cleaning, and probably the rest of the hydraulic system might need a bit of an internal spring-clean as well
No was talking about the pressure valve on top of the hydraulic tank. I can blow/suck air and it has dirt in it. I opened the quick drop valve, 100% clean. Spring looked great. Wasn't stuck depressed. The other side, plunger side I guess, I could push it in and out easily and hear the fluid moving in the ram. Looks like it is working properly
Sorry, I misunderstood you. So we know the quick drop valve isn't the cause of the problem. I don't know how far you want to dig into the system but try this as a suggestion to check for internal blade lift cylinder leakage. 1. Remove the tin covers #1 on the top of both lift cylinders. 2. Pull the pins & disconnect both blade lift cylinders from the blade. 3. Retract both cylinders so that the rods are retracted inside the barrel and they don't move any further. See if you can't put a sling or something on each one to prevent it from floating down. 4. On both cylinders loosen (DO NOT REMOVE) the hose connection under the tin coverthat is circled. That is the return line when the cylinder is moving upwards. 5. Start the machine, set the engine to High Idle and slowly move the blade control as though you are trying to raise the blade. Observe the loosened connections, are you getting a steady flow of oil out of one or the other cylinder, or even both..? If you are the cylinders are leaking internally and appear as though they need resealing.
Sounds good, I'll get it done. I should have a pressure test today as well. I believe you sent a diagram on another reply for which part to hook the gauge up to for lifting the blade?
I'm going to get a pressure gauge. To make sure I get the right one, is 0-290psi good? I don't think the pressures should be over 60, correct?
Personally I would do the cylinder line leak test first. Remember that to test pump pressure the operator seat and the cab floor both have to be removed . You will need a 5000 or 6000psi gauge. The specified pressure is 3500 +/-65psi on Test Point A below. Procedure is as follows: - 1. With the engine at HIGH IDLE, move the bulldozer blade tilt lever to the maximum TILT LEFT or TILT RIGHT position. After the cylinder is at the end of the stroke, the implement pump is at the stall condition. 2. The pressure reading should be 3500 ± 65 psi. Note: Do not hold the machine in the implement stall condition for more than 15 seconds at a time. Wait 1 to 2 minutes before going back to the stall condition.
Just curious, why does the pressure test for the two front lift cylinders require tilting of the blade to test? There is a separate third smaller cylinder on the right side of the blade arm that does the tilting. I figured you would put the gauge on the pump then pull back to lift?
The main implement (hydraulic) pump supplies oil for all the functions. Blade lift, blade tilt, ripper (if equipped). To a certain extent it doesn't matter which function you move, but the presence of the QD valve on the blade lift circuit could be sufficient to skew the results. The accepted form of testing pressure a tractor implement pump is to use the blade tilt circuit.
Blade lift has topping valves that open when the pistons reach the end of their stroke. They allow oil to bypass through the pistons so they don't impact on the ends of the cylinder barrels. I do seem to recall a separate pump for the rippers though. I think it was piggy backed on the main pump. That could be model specific though.
First picture is where I believe the trans breather goes? It just has some thing with a hole in it. Is this the right spot? Second picture is the trans breather. Third picture is the pump and fourth is the gauge. The gauge doesn't match the connections on the pump. I asked cat if they're the same and they said yes. Going to call them now. Are the two rounded spots on the pump where I hook up to? Is that the correct trans breather location? Also I did the Piston test, I had them fully in, with connections cracked. I pulled back for up and at first nothing then oil started leaking faster after a while, seemed like it wasn't getting pressure at first then started to
So I got a good look at the trans breather now. It's just completely missing the breather and the little adapter that goes with it. Will go back for the adapter. The gauge is the wrong gauge, they say I need a different one that's $1,000. I think I'll try to find an adapter for this one or something
If that gauge is for the pressure range you want to measure I say BS on the dealer. I'm going to assume you want to check pressures a the two point with the red arrows in the picture below. If that is where you need to hook up the gauge you need one of the 187-3546 Couplers from Cat at about $56.00 and a hose to connect the coupler to the gauge. The hose could be purchased any place that make hydraulic hoses as long as the know what pressures you will be measuring.
Awesome thank you. I'll get that part, get a hose and test the pressure. Yes those are the spots I'd like to hook up to. Looks like those are quick connect parts that can be taken off and possibly use the gauge I have but I'd rather get the hose and connection.
You can get the coupler and hose along with any pressure range gauge you might need for far less money than a Cat dealer wants to charge you at most any hydraulic supply house. Spencer hydraulics and Motion & Flow Control Products. Inc are two good suppliers that I believe are nation wide.
And it might be a good idea to get new rubber covers to keep the dirt out of the fittings. I might be able to get the Cat numbers or the place John C suggest might also have them at a better price.
Dust Caps are Part Number 6V-0852. $4 each from Cat. Talking about your trans breather. You have something missing from the machine. See below. I believe that the hose in your photo is Ref #41. You can confirm that by checking the Part Number on the aluminium tag about 2" down the hose. Is it 9U-8249..? If that hose is open you have dust falling straight into that opening and ending up in your power train oil system. See the sketch below. There should be a tee that connects into a tank (maybe), the illustration is not 100% clear and I'm not there at the machine. I think you are missing items 38, 39, 40, 42, & 43. You have a new breather 44 and you have the end of the hose 41. It just need to be determined exactly where the tee #39 actually installs. There must be a connection very close to the end of that loose hose shown in your photo with (I would hope) a plug in it.
Good long distance catch, Nige.
Yes would be handy to know what that tag says in the image that ends with 8226-JPG Here is what SIS shows for the location of the transmission breather:
I'd be interested to know what is in the hole where the tee is supposed to screw into the case of the machine - arrowed. If that is open like the end of the hose then major amounts of dirt have been getting into the transmission via the back end of the machine as well as what has been getting into the converter via the open end of the hose. From the looks of the photos that machine needs a good pressure washing in the area of the Hell Hole before the floor goes back in. I can see at least one oil leak, there may be more under all the dirt. After all the effort to remove the seat and raise the floorplate IMHO it would be time well spent to get things cleaned up under there and fix any leaks that are visible before putting the floor back. But BEFORE hitting it with the pressure washer all the open holes, such as the hose for the missing transmission breather, ought to be closed up or fixed. You don't want to be washing dirt into the machine systems.
On another note,My D8R handbook states that speeds on the implement pump can be slowed or sped up? I had an implement pump failure a couple of years ago,s/x pump from Cat was around 5k. Put clean up filters in it and worked fine to this day. However,I swear it worked slower on the lift,but it doesn't really affect the job. I also change the engine oil,fuel,steering and tranny filter every 250 hours with new engine oil at 250 hours,tranny oil 2000 hours and final drive oil every 500 hours. Hyd oil at 2000 hours too. I only use Cat oil and filters,and some will say I'm throwing good oil away.
I'm looking for the breather and T location now. Between the trans and torque converter would be under the floorboard more toward the front right? I don't see anything toward the back
Here's the breather I believe. That hose that connects to nothing is something else. It's directly under the left side of the seat. I'll try to get a number off it. Everything is pretty dirty
6Y4046 F01 This is the tag on that hose
You are correct. That is the breather. 6Y-4046 is one of two hoses on the steering lines. I wonder (out loud) if someone has bypassed a filter somewhere..? Can you find where the other end of that same hose goes..?
So far I followed the hose and it goes under the left fender area. Will have to take more apart to follow it
I’ll see if I can post up some info regarding where the hose goes. Not too good, but you might get the idea. This is looking from the front of the tractor towards the back. It appears as though they come from the steering pump and end up somewhere on top at the test points for the system (circled). Although the 6Y-4046 don't go all the way to the test points. It only goes as far as the connectors #46.
So that hose is disconnected on both ends. It also has damage in the middle. I think it was replaced and just left there because it's tied to another hose with a clamp. I looked at all connections down there and don't see any disconnected. So I think it's just a trash hose and they didn't want to take the time to unclamp it. Also found this little electric cover. 'Cause you know, burly men don't need instructions. (It was just sitting free on the bottom after I cleaned everything) By the way, did you know these machines are actually yellow when clean?
I'm off to get the pressure hose for the gauge and the quick connect end. Again, I did the cylinder leak test, cylinders all the way retracted, loosen hose, pull back to lift. At first no change then fluid did stream after about 5 seconds. You would think a lot more fluid would gush out so I'll do the pressure gauge test. If the pressure is good that means repack the cylinders? That was one think I said needed to be done before I bought it but they obviously didn't.
So I sent a picture of my machine that looks like it matches A and B. You said tilt the blade all the way then I connect the pressure gauge to A and tilt the same way and read pressure then connect to B and do the same thing? Both can tilt left and read pressure from both separately?
Answering your last point first. Blade on the ground, connect the quick coupler and gauge to Test Point A. 1. Start engine and set throttle to High Idle. Note the pressure on the gauge, it should be around 435psi. I know the gauge you are using is a 6000psi one and it won't be totally accurate at that sort of pressure, but it will give an idea. 2. Reduce engine speed. Raise the blade so that the lift cylinders are about half-way. Stop lifting. Tilt the blade all the way to the Tilt Left or Tilt Right position (makes no difference which). When the tilt cylinder will not move any more, keep the control in the full Tilt position and raise the engine speed to High Idle. Record the pressure on the gauge
As John C posted earlier, the blade lift cylinders have valves in the pistons that when the cylinders are at full stroke oil can pass from one side of the piston to the other, so what I suggested will not work. Instead try a lift cylinder drift test. 1. Check the hydraulic oil temperature. Use the temperature along with the table below. Make sure you get the hydraulic system at least a little bit warm. 2. Lift the blade until the cutting edge is approximately 300 mm (12 inch) off the ground. Put the dozer lift control lever in the HOLD position, stop the engine. 3. Measure the extension of the lift cylinder rods from the lift cylinders. Record the distance that was measured. Wrapping some insulation tape around the chrome rod gives you a good point to measure from. 4. Record the distance and check the time that the cylinders extend. Compare the readings with the chart below.
I'll try this lift test. However I can tell you that the blade stays up forever, doesn't really go down on it's its own. The rippers go down over a shorter time, an hour or so, but the blade stays up
The quick connect doesn't fit :/ Seems too big. I'm asking cat if they have a smaller one
You need to make sure all the pressure is out of the circuit you are plugging into. You will need to make sure all the implements are on the ground first, removed the hydraulic tank cap slowly and let off the air pressure and then move all the controls around with the engine off to make sure all the pressure is gone.
I can push the inner circle on the male part in with a tool and it keeps leaking. Do I push until the leaking stops? It still won't connect
Can't get the gauge on so I pushed the tool in the quick connect while the machine was running. I got a nice shower. Must be the cylinder or something wrong with the control. When I pull it back it doesn't have any pressure. I wonder if it got disconnected somehow
Moved 1.25"
I got to the control. The one that controls up and down has some black build up on it that looks like a tiny leak. Could that be the issue?
Is that lever moving when you move the big control lever?
Yes it is moving up and down. Also on the quick connect the gave me I think it's too big. When it's "closed" I can completely push t on the dozer connect and wiggle it around
However it does have pressure and spray everywhere when the engine is on
I can only remember one size for the fittings on the Cats. You shouldn't be able to wiggle it around though.
Any opinion on the valve connected to the lever having oil on it like that?
Is there a procedure to bleed the hydraulic line and pump?
I think that is just oil the is seeping out of the flanges on the casting. The unit does look like there is another lever inside that moves the spool. If it was me I'd clean that off with air pressure and maybe some brake clean or ether and see what it is all about. Sometimes there is a piece of linkage in there that might be amiss. If you have a parts book you might be able to see what is inside it.
Are you saying it only moved 1.25" in the time it should have moved 1.5" at whatever the temperature of the hydraulic system was at the time..? You do NOT connect that type of quick coupler to a running machine under any circumstances. You must stop the engine, wiggle the blade and ripper controls to relieve any residual pressure that may be in the hydraulic system, and ONLY THEN connect the quick coupler to the test point. What did you get for a quick coupler..? The Cat Part Number is 6V-4144. The inside diameter of the coupler in the RH photo should be about the same diameter as the outside diameter of the machine test point in the LH photo. If that is not the case you were sold an incorrect coupler.
I didn't have a tape measure with me so I just marked it with my finger. It was easy to see. Yes it went down about 1.25-1.5" in the proper time. As for connecting the coupler, I tried several times with the machine off but it's way too big, with the coupler locked I can put it all the way on and wiggle it around. On the other post I was told it was part number 187-3546. I can get the new part number if that's needed instead, I did have a custom hose made so I hope it uses the same connection! So I get 6V-4414? I actually used a screw driver to push so that I saw fluid come out. Since I couldn't get a reading I just wanted to see hat oil spray so I have an idea it's working. Nige, any opinion on that pump valve slight leak? Could it have air in it because of a slight leak? Someone else is saying their convinced there is air in the system. Is there a prime procedure?
Going to go get the right coupler, I thank everyone for their help and don't care that the part number was wrong. I'm very grateful for everything. Nige, if you happen to have a diagram that shows the supply and return hoses for the blade lift that would be great. Someone who works on military d7's told me to crack the fitting at the cylinder and pull back on the handle then while pulling tighten it, then do the same for the return at the cylinder then return at the pump. Just like brakes on a car. Hopefully that will be the culprit. Otherwise if pressure is good and I bleed it properly it must either be a repack cylinder job or rebuild pump job. We shall see. Nige, you said it is standard to use the tilt for pressure test. I noticed the tilt has 1 valve, the ripper has 1 valve and the lift has 1 valve. The lift valve is leaking slightly, I guess class 1 leak. Is there a way to test the lift valve in case that's bad while the tilt is good?
Based on the drift test I think both of your lift cylinders appear to be pretty good. If the piston seals were failing and the hydraulic oil was hot I reckon you would almost be able to see them creeping down while you looked at them, That's how bad "bad" cylinders are ……. Let's get a reading of pressure on Test Point A with:- 1. Engine at High idle and all the blade controls in neutral. 2. Engine at High Idle, the blade half-way up and the tilt control held hard over with the tilt cylinder at the end of its stroke. Do it with the tilt in both directions and see if it makes any difference. I suspect it won't. 3. Engine at High Idle, blade on the ground with the tilt in the centre, pull the handle to full raise and watch the pressure gauge. Report exactly what it does. A while back when we were discussing your oil analysis results you may recall that I pointed out that the viscosity of the sample that came out of the hydraulic system corresponded to an SAE30 oil. I wonder if the previous owners had this performance issue (possibly caused by something worn in the hydraulic system) and "fixed" it by switching to a higher-viscosity-than-normal oil to hide the problem in order to sell the machine..? You've changed the oil back to a 10W and now the problem in the lift has reared its head. I just wonder if the two are related..?
All functions are fed from the same pump, this test is designed to check the pump function. Get that one done first and we'll see where we go from there.
John C has been following this thread. Here is the Hydraulic System & Implement Pump SysOp. Somehow I get the feeling that the pump is not upstroking when blade lift is called for.
In reviewing that first schematic, I believe Nige is correct. It looks like the compensator valve spool above the blade control spool might be stuck in the wrong position. It is normally open because of the spring pushing it to the left and has what is load sense oil pushing along with the spring. Pressure oil from the pump pushes against the right side of the valve to close it. If that valve is stuck in the wrong direction, no oil goes to the blade lift function. Looking at that drawing reminds me why I absolutely hate the way Cat tries to explain how a hydraulic circuit works.
150 psi sitting, 700 psi doing everything else
Here is a picture of the trans screen. It has rubber/plastic in it.
Let's put the transmission screen on the back burner for the minute - although the black particles look like bits of burned clutch material a) there isn't a whole load of them and b) if you have no idea when the screen was last removed you can't say for certain that they accumulated in the last few weeks for example. That material could be months or even years old. Please correct me if you had the screen out recently. Can you explain the "150 psi sitting, 700 psi doing everything else" comment..? Does that mean 150psi pressure with the engine at High Idle with no blade control handle movement, and 700psi if you stall the tilt function..?
It's not the best Hydraulic SysOp I've ever seen, that's a fact. See if the Hydraulic Schematic helps at all.
Yes it's at 150psi high idle and 700psi high idle stall
Another tech is saying that since the rippers and tilt are working I can't blame the pump for the failed lift. What do you think? Air in the lift line?
Sorry, I don’t agree with him. If you stall the tilt and are only getting 700psi instead of 3650 or something similar that the specification says then the pressure you are measuring is way low. Even though on the face of it the ripper and tilt functions appear to be less affected than the blade lift that doesn’t mean they are working 100% as they should. You are measuring a pressure that is only 20% of what it ought to be. That ain’t right.
So the pump must be rebuilt or replaced?
Only if that is what the problem is. Right now all we know is that the pump is not developing the amount of pressure that it should do. The implement pump is a variable piston type (read the 2nd attachment above) and has a hydraulic control circuit that effectively tells it when to perform. If that control circuit is not functioning as it should then the pump will not work correctly even if there is no problem actually inside the pump itself.
What is the fix/test to see if it is upstroking?
I'll have to download the complete pump performance testing procedure. It'l be tomorrow. When you see the procedure your first thought may be that you'll probably want to get someone in to do the work. It will be much more complex than what you have tested so far and require a large-ish number of different guages, one of which I'm fairly sure will be a differential pressure gauge.
Sounds good. So it looks like I need to have the main control valve taken out and torn down/looked at. Is the main control valve what the level directly connects to that's sitting on top of the pump?
Nige, I see I must have given the wrong information on the coupler. I have spent a good amount of time trying to find information on the couplers and adapters but seem to be going in circles. I did find one place that referred to the 187-3546 coupler and it seems to indicate that is a coupler of pressures up to 8,700psi So I'm thinking Cat uses two different coupler systems based on the maximum pressures being tested. Is there a reference paper somewhere that puts all this in one place? Would also be handy to have a listing of the fittings the couplers mate with giving the thread types and sizes. To Robert0769, I apologize for giving the wrong information
No problem at all, it led to the right information! I appreciate all the help
By the way, I drained all the oil in the trans and torque converter today and it only drained 15 gallons total. Then 15 gallons to fill. I asked cat if it all drains from the rear screen and they said yes.. but then they tell me it takes 45 gallons. Little strangeness there I wanted to report. Kinda makes me feel like I'm nuts
You missed something for sure if you only got 15 gallons out. Did you drain the main tranny case from the big plugg directly under the machine
That schematic is wonderful. Testing to the pump means you have to read two pressures at the same time. You will need output pressure on the pump plus load sense pressure going back to the pump. Pump pressure should but around 300 PSI higher than the load sense pressure. If the difference is there you have a pump problem. If there is no difference, then you have a problem somewhere else. Since you haven't done it before and are having problems interpreting what we are getting at, I would suggest getting someone with experience to help you. As far as the pressure tests go, did you check pressure on the ripper circuit as well? I see that implement pump also supplies charge pressure to the steering pump. Out of curiosity, how did the steering work for you?
Could you perform this check please. it is a simple test of the resolver system that controls the pump out put warm machine hydraulic system engine at high idle hold lift lever to full lift position while holding lift lever operate tilt control both ways while holding lift lever operate ripper control both ways while holding lift lever operate the steering control both ways if in one of these positions the blade lifts, you may have a faulty resolver on that circuit John I see that implement pump also supplies charge pressure to the steering pump. Out of curiosity, how did the steering work for you? The implement pump only supplies charge oil to the steering system when the steering system charge oil is below approximately 290 psi Mark
I think sleeping on it overnight was the key. I may have hit the jackpot. There IS a bleeding procedure for the implement signal circuit, but it's hidden away in the Testing & Adjusting section and quite frankly I only came across it by accident while reading through a 60-page document. I must be sad...….. First, let's get oriented. Below is a couple of views of the implement pump. The pump pressure control valve is circled in the two views. I'm not sure which of the two views relate to the way the pump is installed in the tractor so I included both of them. The valve may be on top of the pump, it may be on the side.
Next, here is a closer look at the pump control valve. The bleed screw #18 is circled. The bleeding procedure is: - 1. Stop the engine. Wiggle all the control levers (lift, tilt, ripper) to release any pressure in the system. 2. Unscrew the bleed screw 3 turns ONLY . ( Will require a metric Allen Key to fit the plug) 3. Start the engine and run at LOW IDLE ONLY . A small amount of oil may come out of the bleed screw during the procedure. The following steps may cause the implements to move. Be prepared for that and ensure that people keep well away from them. 4. Move the blade tilt control lever to full tilt in one direction for 5 seconds then return it to neutral. 5. Move the blade tilt control lever to full tilt in the other direction for 5 seconds then return it to neutral. 6. Repeat steps 4 & 5 for the Blade Lift control lever. 7. Repeat Steps 4 & 5 for the Ripper control lever. 8. Close the purge valve before stopping the engine. NOTE: It is important to perform the procedure in the order of Tilt->Ripper->Lift because it starts at the cover end of the implement control valve and works to the other end. Performing the procedure in any other order is not guaranteed to get all the air out of the implement signal circuit.
Here is a photo of the pump position on the machine
Mark, is that the bleed screw that I've circled..?
Robert,when my D8R implement pump failed,the ripper and steering seemed perfect,however it was stopped immediately. If I recall,the tank and lines were drained as best as possible and all filters removed.We also took part of the tank apart to remove any debris. In fairness,the filter and tank were clean but we still used clean up filters for the first day or so. The pump itself was fed with oil as well prior to firing up the engine.I wasn't present to see it bled,but it's worked for 3 years since.I have changed the hyd oil on it myself a few days after the fault,but I genuinely can't remember any problems with bleeding the system. I think I just let it idle and operate the blade and ripper with the filler cap off? For the record,there was just one of the 4 valve chambers at fault,so I got 2.5k of my 5k back a month later.
A lot of good things to try now. The pressure from the pump was 700 for tilt, lift and ripper. The only way to get the blade up is to pull up and tilt at the same time. The blade does slowly go up in reverse but not forward. I did not do any steering while looking at the gauge. I will do so. I do have a question, picture number 1 is the side view of a pump I've been testing at Port A.. and picture number 2 is the top view of the main valve I believe. Am I correct so far? So where is the main implement pump? Is the implement pump picture number 1?
I did not, Cat said no need to touch it since the rear screen housing drains it all. Much more knowledgeable here it seems. I mean I asked them for the main valve body rebuild kit and they refused and said my only options with them are a new one or rebuilt one, they will not sell or make a list of parts for me to rebuild myself
If you follow the lines from the Test Ports A and B backwards it will lead you to the implement pump. Sounds like you need a Parts Manual
I've used four different allen wrench sets and none of them fit because there is no clearance between the valve and the pump. The short sides are all too long. I'm thinking maybe if I get a allen bit and use pliers.
That is the correct part right? It has port A going directly to it and matches in shape. However it does not have a bleeder hole as shown on the picture next to a hose outlet. I'm suspecting it may not be the same thing
that's it Nige it is similar to the G and H series graders and uses the same procedure to bleed the signal line Looking at the ops picture he has the allen key in the wrong fitting. The bleed screw will be underneath the signal hose. the hose will need to be loosened and moved out of the way Mark
Yes I agree, I see where the hose is in the way and needs to be moved, however there is no bleed screw there. I had a friend look too in case I'm seeing things but it's all solid. I'll get a better picture
Zooming in on the component where the bleeder should be. There is only a hose, not a bleeder nut
What about this? Test point B leads here
Due to the age of the machine the pump or compensator has probably been up dated and in that case is self bleeding tell us more about what happened for the simple resolver test Did the lift feel like normal when you operated the tilt control?
It does not lift when operating the ripper. For half a second it did lift but then stopped and didn't happen again. It does not lift when tilting up however since one side is up with tilt it won't go down unless I push down. Sometimes in reverse it raises very slowly
Looks like I need to have the control valve rebuilt and if that doesn't do it have the pump replaced. Must have been a coincidence that it happened right when I changed the hydraulic oil
In order to remove the control valve I'll have to drain the hydraulic tank correct? It will gravity flow all over if not?
Go back to one of my previous posts regarding your oil analysis results stating it was unusual for a machine to have SAE30 oil in the hydraulic system, especially one that came from somewhere up North. Was the previous owner masking an existing problem by putting a higher viscosity oil in the hydraulic system and you exposed the problem when you switched to SAE10W30 oil..?
You feel I should try putting 30wt in?
At this moment I really don’t know what to suggest, all I can say is that if it had 30wt in it before possibly the reason was to try to cover up a problem. If you want to give it a try with 30wt then go ahead. If that “fixes” the problem then at least you know that something is wrong in the hydraulic system that at some point will have to be properly diagnosed and fixed.
I generally keep my nose out of threads when I have nothing intelligent to add, but is there really enough of a difference in the viscosity of 30wt vs. 10W30 when cold to matter? If it doesn't lift now, I sincerely doubt it's going to magically lift with 30wt.
An SAE 30 oil is approximately 2.5 times the viscosity of a 10W when cold. It may make a difference.
At this point you would be money ahead to get a professional out there to do the diagnosis and find out exactly what is wrong. It's not doing you any good to keep jumping around between here and the machine trying things and all we can do is suggest what might be going on.
10W, yes. I haven't read the whole thread, but you said in post #173 he put 10W30 in, and 10W30 is a bunch thicker than 10W, in my experience.
Before you pull the control valve, and it is a pain in the ar$e to remove, have a look at the main relief valve, as it is common across all controls. At this stage you have nothing to loose
Any chance someone has the model number of the unit? Going to have someone come out
How do you mean, model number..? I thought that all along we've been talking about a D8R....
Yes Cat is busy for 3 weeks and a different company asked for the model number of the pump/control valve. I don't see a model number tag
Everything on that tractor is Cat-designed and built. No model numbers AFAIK. If the company is asking it indicates they have never dealt with one before, so are you going to provide the training tool for their people to learn on and be paying them an hourly rate at the same time..? Just thinking out loud.
Agreed. After I posted asking about the model number I called cat back and put myself on the waiting list. I'll wait for cat
Asked Cat to come out with a flow meter and anything else they can think of to diagnose. They said they'll bring it and they can figure out if it's the valve or pump Guy gets out here, doesn't bring flow meter, does a pressure test I did and says he can't tell what y would be and there's nothing else to diagnose in any way. Talked to management they said they'll have him come back with a flow meter.. I said no disrespect but I need to know which part to send in so they can fix it so if he can't do that then don't send him back. Talked to a friend who used to work for cat who said they got rid of field techs with lots of experience and only kept the shop master techs so don't expect to find anything out. We'll see if tech comes out with flow meter but other than that looks like I'm guessing at which part it is. Pump or valve
They sent out a different the who took off a k4 or something like that. They said the pump is dumping almost a full bucket of oil when it shouldn't be dumping any. They said the pump is bad and needs to be replaced
They also said the hydraulic system is full of dirt. Weird but I wonder if the person who put dirt down the engine oil fill also put it in the hydraulic oil fill.
Sure don't want to put a new pump on a contaminated system.
How would they know the system is "full of dirt?"
Said he cut the filter open and it's full of dirt and metal. I think it's weird since I just replaced that filter and haven't run it but I wasn't able to be there, dad passed and had to go out of town. So I'm going to clean the hydraulic tank/hoses and replace the pump I guess. I'll call and ask where the filter is and if they have pictures
????
Pretty much
Just got the quote from cat to replace the pump. For labor they said it would take 60 hours to replace the pump and flush the hydrologic system. Anyone have an opinion on this? This cat dealer has been jacking me around since day 1 and 60 hours to change the pump sounds excessive. I was hoping to spend a few thousand having them do it but I can't stomach 10k in labor over 1.5 weeks for a supposed professional to change it
Hey Nige, any chance you or someone else has the procedure for replacing the pump? Like torque specs and stuff?
I was thinking no more than eight hours on site if they brought the pump and all the seals and suction hoses. It kind of has that giant sucking sound Ross Perot was talking about all those years ago.
My 2c. The hydraulic system is full of ****, that much is obvious from the oil analysis. To install a replacement pump in a system as badly contaminated as this one apparently is - that's just asking for another failure, either the pump or something else in the system. If the dealer is quoting 60 hours (Question: Is it a quote or an estimate and they bill on actual hours.?) to replace the pump AND to perform all the necessary cleaning/dialysis on the complete implement hydrauklic system which of course includes the steering then the time may be justifiable to a certain extent. The fact of the matter is that this particular tractor is a very tired dog. The OP has had the wool pulled over his eyes at every turn by the seller from the time he looked at buying it, that much is obvious from the amount of trouble he has had with it simply because in a previous life the tractor was not cared for. My opinion, other options may be available.
I have changed one of these in a good day on a D8R.Heavy old job and 8 or 10 hours. However,my system was pretty spotless and I kept returning myself to change the filters. In your case,it seems your system is badly contaminated and the other 50 hours of coming and going may not be enough. I've never had to completely clean a system out on a hidrive,but it could entail removing every single hose or even rods to clean it up. Back in 1994 we had a bonny D9H that blew a pump good style. It unfortunately wasn't cleaned out properly and spent a year breaking down afterwards nearly bankrupting it's owner. I believe it scored all the rods and barrels in the end.
I got the remove and install instructions for the hydraulic tank and the pump from Cat. I realize it's a heavy job but it's crazy simple. No torque specs or anything. I'm going to open the tank and clean it out, look inside hoses and decide if new ones are needed then replace the pump. Cat said it has a refund of $1,700 when I return the core however they said if the core is damaged then they'll give less which sounds scammy to me since the only time you return a core is when it's been damaged but whatever. Get it done and go to work. As soon as I'm able I'd like to find a different D8 however by the time t comes to that I might have already rebuilt the whole dang dozer haha. Then there's always the risk of another snake salesman tricking me. One thing I learned.. before buying a used machine pay for samples of all fluids, open up the final drive to inspect and look at all sensor connections to make sure none are bypassed. Almost makes me wonder if I'm a rare find in when I sell a used car or something I actually fix it all up nicely and don't hide anything. Treat how you want to be treated. I'll let you know how the install goes. I'm also buying a GoPro to film the whole thing so if the blade still doesn't lift I have proof for Cat that I did it all correctly
The idea of a Remanufactured hydraulic pump (which is what I assume you are buying) is that you have to hand back to the dealer a worn out component that is capable of being rebuilt and then to be sold again to someone else. I show the implement pump as Part Number 0R-8503. Price is just over $3k with a $1700 Core Credit. A new 9T-8346 implement Pump Gp shows as $4860. There are three possible scenarios - Full Core Credit, Partial Core Credit, and No Core Credit. Your old unit will be inspected at the dealer against a set of specific criteria. In other words is it complete, does it rotate, etc, etc. If it passes all the inspections then you get full Core Credit, $1700 in your case. If it only passes certain of the inspections but not others then you would get Partial Core Credit, if it "fails" the inspection cirteria you get No Core Credit. So you would be in for almost $4800 under those circumstances. The price of a Reman component of any type plus No Core Credit refund is equal to the price of a brand-new component because that's what Cat has to put into their parts system to replace the unusable one you (or anyone else) handed back, even though the brand-new one goes in a box with a "Reman" label on it. A percentage of all Reman components are actually brand-new because obviously not every old component that is handed back is in a fit state to be rebuilt.
Pro tip. If you buy a Cat reman part, don't throw the box away. If you don't return the old unit in the original box you won't get a full core credit.
My learned friend makes a very good point. Do NOT throw the box away....... Acksherley there ought to be some "Do's and Dont's" paperwork in the box with the Reman unit telling the buyer what they are supposed to do, returning the Core back in the original box being one of them. But of course who ever reads them..?
I actually got Partial Credit on a 3304 block where the rod had exited the side of the block in trade for a short block Reman. I sure didn't ask why and I signed the paperwork as fast as I could. Then I went inside and paid my account in full before they could change their mind.
Hello Nige, I am new here and and wanted to say thank you for having me in the group. I am wondering if you can help me with finding a wiring diagram for a wheel loader; CAT 930h. Looking to find the source of power to a couple diodes that supply power (or are in line with) to the fuse that controls the front and back main external lights. (Would be headlights and tail lights). I found two completely burnt diodes under the fuse box and when i replaced both diodes, after extensive “wiring short” hunting I only have power to the diode supply wires (one diode 24v supply is blue other diode 24v supply is yellow.. both wires on output of diodes are purple) if I turn the head light switch on to either position 1 or position 2. Is this normal? Also is it normal that this machine allows head and tail lights to work with key out of ignition? Also wondering if you could help me find a wiring diagram for the magnets on the joystick? With kick out switch Engadged, i have green light on both the magnet switch on the boom and magnet switch by the bucket. But no power to the magnets on the joy stick
To get the correct schematic you will need a serial number as there are a few of them for 930H SWL you would get more response if posted in the wheel loader section Mark
And one other thing is have the thing assembled if it is say a pump or starter, at least make it look like it was when removed!
Thank you for the suggestions. They didn't have me sign anything or tell me anything or send paperwork with instructions. I'll make sure to have it assembled and sent back in the box that was given to me. It's just a plywood box but I'll make sure. Going to get a GoPro to film the whole thing now then heading to the machine.
I contacted Cat and asked exactly what they did to see the pump is bad. They said it's a K-strain test. Disconnect the highlighted hose, full throttle stall a component and it should give 1.5 gallons a minute or less. They said at idle without stall it was dumping 5 gallons every 10 seconds. Hopefully this makes sense to someone and you agree.
translation -- K-test will be case drain test which measures internal leakage of the pump Mark
And if it's dumping that much oil the pump is most definitely foobarbed.
Not wanting to derail this thread, but I sent you a PM.
Robert, Cat will play fair on your core charge. I stripped my failed D8R pump out of curiosity and it wasn't too bad. I got about 1500 back if I recall
I was thinking about stripping the core myself just to see if it's totally broken then see what they refund. So I finally got time to work on the dozer. The hoses took 1 hour to get off, the trans pump took 20 minutes (2 bolts), the implement pump has 4 bolts. I took 3 off in 10 minutes then fought for literally 5 hours on the bottom bolt. The housing was in the way. I made 3 trips to a store for different tools until I finally realized I needed a swivel ratchet wrench. Once I got that I had it off in 20 minutes. Total tear down about 7 hours with the 5 hour hell learning curve. Put implement pump on in 10 minutes, all bolts on in 10 minutes, forgot to hand tighten one bolt and it got stuck against the pump frame so took bolts back off a little to hand tighten that last bolt and tighten with wrench. Add another 15 min. Trans pump was a breeze, 10 mins to install and tighten bolts. About 45 minutes to install. I asked cat for all seals including o-rings for hoses. They said it was all there but they forgot the o-rings. So I'm going tomorrow morning to get the o-rings and expect 1-1.5 hours to put hoses back on. So total install will be about 2.5 hours. If I needed to take the whole thing apart again I bet I could do it in 3 hours. Even with my 5 hour wrong tool mistake, a guy (me) with no mechanic experience on heavy equipment did it in less 10 hours without the right tools, 1/6 the 60 hours Cat said they would need. Adds to my mistrust of Cat. That along with them trying to charge 8 hours for the diagnostic.. then I said hey you called me at 9:30am and said it's done so why 8 hours? Then they responded saying oops you really owe 4 hours, our bad. Mhmm... Oh and they were also going to charge 20 hours to clean all hoses.. but also had all new hoses on their parts list, which hoses are custom built and non refundable so I said I'll get if needed, but still they said they were going to charge 10 hours to clean hoses.. new hoses.. very dubious. Now for the dirty hydraulic tank. All hoses are clean but I cleaned them anyway with water and rags then let dry. Took 30 minutes since hoses were already off and only had 3 hoses connected to the tank. I tore down the entire fender around the tank and opened the tank, used a electric gun so that whole process took 10 minutes. There was about 3 hand fulls of dirt and rocks inside the tank. Good thing the tank sucks oil from the middle. Covered the intake, took a hose and blasted everything out then wiped with non lint towels. 15 minutes. So cats 20 hour quote to tear down and clean took me 1 hour. Granted I didn't hook up a bladder and run everything to clean out any oil in the hydraulic pistons but since none of the hoses had any dirt in them even with the tank having dirt, I'll probably either change the hydraulic oil once or twice very quickly OR disconnect the return lines from the blade and ripper and let it spit out that old oil. Either way it will be taken care of quickly. The whole process was very simple. It was hands on with heavy stuff but simple. Tomorrow is the big test to see if the pump was really bad or if it's a stuck valve. I'm still very skeptical of Cats diagnosis for two reasons, one they said they cut the hydraulic filter open and it was full of dirt and metal. Reason for skepticism is they didn't cut it open, and when I cut it open it contained no dirt or metal. Then two, they said they removed the line in the picture below and that's the k screen test which should give 1.5 gallons of oil at full rev and stall however mine gave 5 gallons in 10 seconds at idle. From what I just experienced with those hoses and oil, I find it hard to believe the one tech working by himself was able to disconnect a hose while holding a 5 gallon bucket way down there then turning the machine on from up top without spilling a little oil..then on top of that if they took out 5 gallons like they said the tank should have been 5 gallons lower but it was totally full. But then again they do have OSHA on their arse for any drop so maybe he did do it clean, but doesn't explain the filter not being cut or having dirt/metal and also why the hydraulic tank was full when they said they removed AND wasted 5 gallons. Tomorrow will tell if they really did a correct diagnosis
Dozer is up and running again. 3,500 psi at stall for ripper, tilt both ways. 1,000 Pai for lift which I assume is because of that recirculating thing that made it so I couldn't do the test on the lift cylinder by loosening the hose and going to stall then looking for more oil spilling out. Back to work tomorrow. I'm going to keep the gauge on permanently ha
This is the hose used for case drain to test the pump. When removed, at high idle stall it should leak 1.5 gallons a minute.
What's your plan going forward for replacing filters & (maybe) changing oil again to get any residual dirt out of the system..? I would suggest to run the machine for a short time and have a sample of oil analyzed, but make sure that your request for the analysis includes a test for the ISO Cleanliness Code. It's not included in a standard test AFAIK. Post your results back here.
I was going to drain and fill again after a short while but I'll do the sample first instead and let you know. I will probably go around 80 hours and change the filters if the sample is good or change oil and filters if needed. I'll ask for the additional info I really appreciate everyone's help
I'd go no more than 50 hours before taking another oil sample and changing the filter at the same time. Call me suspicious, but...…….. do you have any idea how all the dirt might have got into the hydraulic tank..? Do you have/had any disgruntled ex-employees or similar..? Have you considered using the locking mechanism on the caps if they have them..? (If not it's simple to install)
DITTO, DITTO S.Calif, locking fill caps are required. Disqruntled everyone, almost. Even use locking night switch (master electrical switch) is a good idea. Switch from 777 trucks have locking feature.
I have all compartment locks on all my kit.These systems are too open to contamination from disgruntled people
We have locks on engine, hyd. and trans. compartments as Iam terrified that someone will empty a fire extinguisher into one. More often than not, we leave fuel tanks unlocked, figuring that it is better to lose some fuel rather than have them stick a crowbar through a plastic tank or go looking for trouble elsewhere on the machine.