does anyone have the engine hi idle specs for a d8n with a 3406 in it regards
Tractor (or even better - engine) Serial Number...?
The 3406 went in 1000.s of diff. machines.. The speed could be anywhere from 1800-2600.. or higher. GOTTA HAVE a SN..
What are you attempting to do that you need to know this? Only reason I ask is if you're diagnosing operational issues, that's fine. If you're digging around in the fuel pump, there might be other pertinent info you should have, and without knowing that fact the guys might not share something important.
Turn it no higher than 2600 "no-load" & expect a 10% drop in rpms when its working.. THATS how its designed.. IF it drops lower than around 10% u have an issue.. ..could be a fuel "supply".. or a governor issue.. or your doing something w/ the machine its not designed to do..??
A badly adjusted decelerator linkage will cause a decrease in high idle rpms.
I think you better check your book, 3406 is almost all 2100 high idle although some fire pumps could go 2300. Bob
9tc is the tractor 70v25461 is the engine, customer bought this machine 12 months ago and the engine gradually gets hot and so the transmission gets hot aswell on a 30 degree celcius day and above. seems to take a over 10 mins for it to gradually get temp down to say 85 degrees on engine 95 transmission. water pumps been replaced , thermostat, fan pulleys, radiator, coolers cleaned, im just wondering if the high idle is incorrect and not having enough revs. this machine has done it since his bought it regards
Keeping anything with a little age on it cool is a challenge in hot weather, 30°C is 90°F, that is damn hot for a tractor that size. Is the operator an experienced one? If he's working the snot out of it, it might just be the way it is.
Machine S/N is 9TC01550. Dates from October 1987. Not new, or even new-ish ........ Is that 10 mins to cool down to 85DegC coolant temp with the transmission in neutral and the engine at somewhere close to High Idle..? Belly guards all nicely cleaned out..? Does it black smoke when working hard..? How many hours on the engine & radiator since the last rebuild..? The list of parts you posted that have been replaced. Genuine Cat parts used, 2nd hand parts, or "will fit"..? Coolers cleaned..? What happened to need coolers cleaned.. ? Trans or TC failure..? I'm not a fan of cleaning coolers, prefer to replace them. Any chance it could have something like a wrong turbo or wrong injectors (or both) in it..? Has anyone tried using an infra-red gun to take the temperature of the hose going into the top of the radiator and the one going out at the bottom to check radiator efficiency..? Test Spec for 70V25461 is 0T-6736. High Idle No Load 2225-2345 RPM. Governor setting speed 2148-2158 RPM. Full Load Speed 2090-2110 RPM. Low Idle 740-760 RPM. PM me with an email address if you want the full test spec including governor settings. It's too big to post here.
Can I just add that high idle isn't really measured or adjusted when carrying out governor settings. Note the large range in Niges high idle spec above compared to the governor setting speed, FLS and FTS specs which are very narrow and critical.
3o deg is not hot where im from experienced dozer driver always pushing in first, radiator replaced, transmission failed 12 months ago did a clutch pack, cleaned all system out then replaced trans scavage pump, t/c converter was changed three weeks ago to get on top of issues, dont have any info on engine engine is clean when pushing under load, im trying to narrow down issue thinking that if its not reving hi enough creating a stall when pushing. i put my infa red gun on back of transmission housing it reads 80 degrees then i put it on outlet of t/c where sensor is and it reads 120degrees celcius im thinking that that is normal temp vaue after load from t/c. the sensor and guages have been changed aswell sent a video of machine puhing to a fellow that has one and he said it should push all day like this in first gear
belly guards clean even took side engine doors off to see if would make a difference advised operator to put in neutral and have sitting at about 1500 rpm ive done more on d10t and they cool a hell of a lot quicker but realise all machines are different radiator efficency good 10 degrees drop
I don't know if this is pertinent, but I used to work with a 7H that struggled to cool. After studying the service manual for about a day, and figuring out how the oil flows worked, I decided I needed to check the T/C outlet pressure, and discovered it was out of spec by a small amount. This was over 15 years ago, but if I remember correctly the spec was around 75ish psi, and I was under the minimum spec by around 5 psi. Having tried everything else, I figured out that t/c outlet pressure was controlled by a spool in the control valve on top of the transmission, and decided to pull the valve block and completely disassemble it. When I got to the outlet spool, I found probably the smallest little black particle you could see with normal eyesight in a spot where it could possibly float around and block a small orifice. Put it all back together, cooling issue solved. Not saying this is your problem, but I think you're going to need to get some gauges on this tractor and make sure things are working right. 120°C sounds pretty close to the limit of what I'd consider acceptable for max temp.
Tc inlet pressure is in control valve it was rebuilt at transmission rebuild i put new outllet valve and spring in when t/c rebuild all within spec
Have you checked outlet pressure while it's working? That's what I had to do.
Dam.. I just reread my post.. whoops.. I "mis-spoke".. sorry bout that.. my finger went UP when it shoulda went OVER..
Can you elaborate on what's been done to the radiator? If it's original, you have a folded core type. They were never a great design with very narrow tubes which will block up at the drop of a hat.
Was the trans cooler replaced when the tranny was done 12 months ago..? If it hits the alarm on TC out temp and you stick it in neutral @ high idle the TC out temp should fall like a stone. If it doesn’t I’d say you have issues in the cooler, which is where we came in.......
radiator has all complete new cores, t/c out temp does not fall like a stone, neither does the coolant temp, i pulled the cooler because i thought id found the cooling issue with the aluminium backing plate of water pump all corroded, so i pulled cooler thinking aluminium blocking holes, i rodded holes and flushed out oil side to get any possible dirty material out from transmission. im getting temp differences of 15 degrees from both oil sides of cooler, so cooler never replaced
Think about it, if coolant temp is around 95 and TC out temp is 120 where does the heat go..? If you stop generating heat because the trans is in neutral the TC out temp should fall “like a stone” because it’s 25 deg hotter than the engine coolant temp. Ask yourself where does that heat exchange take place? The power train cooler..... As the tc temp drops closer to the coolant temp the rate of fall of the tc temp will slow down because there isn’t the huge delta that there was to start with. The engine coolant temp will fall slowly below whatever it was to start with, but it won’t fall anything like as fast as the tc temp.
Hopefully I'm not swinging above my pay grade, but I still think this situation is related to the T/C outlet pressure. Getting 15° of differential, and taking longer to cool than what would be considered optimal points to either a plugged cooler, or insufficient flow out of the T/C, which is what I had going on. It's still possible that the cooler could be the culprit if it hasn't been replaced.
Maybe a few boxes need to be ticked here before crashing ahead........just so something basic doesn't get missed. To the OP. So many questions but bear with us here and try to get answers, remember we aren't there with the machine. What oil is in the powertrain (brand, viscosity, is it TO-4)..? I know that it is allegedly not adjustable, but has anyone checked the maximum TC Inlet Pressure when the machine is "cold"..? (I realise where you are in Oz could never be regarded as cold.) What is the TC Out Pressure at converter stall in 3rd speed with all the machine systems at normal operating temperature..?
i will double check t/c in and out at the situation oil in transmission is 50w as advised by local cat dealer, i understand what you are saying but should my temperature of the cooling system be at 100 deg celcius that to hi for me on a 30 degree day, is the temp of the transmission making my engine that hot and as i asked before ive cleaned out all colant holes in that cooler are you saying that the cooler can be possibly blocked in the oil side, should i have quicker differences in temp drop in the cooler,
wouldnt less flow threw the t/c eg higher t/c outlet pressure give less flow to the cooler hense giving time for the cooler to cool the oil?
No. What a torque converter needs is a large volume of oil to flow through it to carry the heat away. Now consider that pressure is the product of resistance to flow . The outlet relief valve resists the flow of oil until the pressure reaches about 60psi, then the relief valve opens and allows oil to flow to the cooler. If the flow to the relief valve is so low (due to internal leakage in the torque converter, a worn pump, faulty inlet relief or other leakage in the system) that the pressure doesn't overcome the relief valve, the relief valve won't pass any oil to the cooler and the torque converter will churn away in in the same oil and overheat. That's also why it's important to check transmission lube pressure because this is created by oil flow from the cooler and the resistance to flow created by the lube system. But then again, internal leakage in the lube system could cause high flow and thus low pressure. (Don'tya just love all these contradictions?) Not to say that this definitely is your problem because, honestly, I haven't been following this thread all that closely, but hopefully to answer your question in post #25.
Agree with Nige and Cmark here, if getting higher temp on the t/c before the relief cut in then the oil going to cooler will be higher temp the cooler is trying to cool from a higher temp resulting in MORE heat being sent to the cooling system. This becomes a self feeding watermelon.
3 comments. 1. Personally I wouldn't use SAE 50 even in that climate, I would be using SAE 30. Either way can you confirm that the SAE 50 oil being used right now meets Cat TO-4 spec..? 2. Should you have quicker temp drops in the cooler - as seen on the TC Out temp gauge - absolutely. 3. A possible blockage in the oil side of the cooler..? Why not..? 12 months ago the machine **** a transmission. The whole oil system (including the oil side of the cooler) would have been badly contaminated with metal and burned clutch material, that by the law of averages at least some of which must have ended up in the oil side of the cooler. Speaking personally my SOP under those circumstances is to CHANGE the cooler. I haven't seen any success stories regarding cleaning coolers out after failures and neither have I heard of anyone who has. Please read, mark, learn, & inwardly digest Cmarks' post above. He has explained exactly why you need shed-loads of oil flow from the converter to the powertrain cooler and what can happen to reduce that flow and cause "overheating". Considering how slow you say the TC Out temp comes down when neutral is selected leads me to believe that lack of oil flow to the powertrain oil cooler (either external to the cooler or inside it, or both) is most likely to be the root cause of your problem. IMHO you should ignore your engine coolant temp, for now at least, and instead focus on why the TC out temp fails to drop as it should when neutral is selected. First step from now ought to be a complete pressure test of the powertrain pressures. See the table of Page 5 of the attachment.
thanks for the advise will get to it and let you know how i go regards
If you need any more info just shout out ..........
I’ve read through everything again and come up with another couple of questions. Sorry....... 1. When the trans was out after the failure 12 months ago did the tractor get treated to a new pump..? 2. Has anyone been into the power train magnetic suction screen recently and if so what did you find..?
Cat Lube Oils ref: 2008 http://oa.upm.es/14340/2/Documentacion/7_C_Maquinas/GuiaCaterpillar/Caterpillar Fluid Recommendations Guide.pdf Page 40 Powershift Transmission / 30C is not hot
Just says scavenge pump.
Ok just went to the machine yes scavage and trans pump were both changed cleaned out trans screens 20hrs ago no material or object in screens cheked inlet pressure 105psi hi idle 3rd gear stall 95psi outlet pressure 55psi 3rd stall Hi idle macine is 2271 rpm stall is 1760 rpm machine has sat for a while i stalled in 3rd got trans to 120 degc and hi idled and dropped like a rock im getting machine hot and in working conditions and going to check cooler differences
I need a spreadsheet with a key legend just to track all the variables in this thread... In Out Up Down Hot Cold Hi Low Cheers
I'm honestly not trying to give you a hard time, but can you repost this with some punctuation?
Is this what you mean..? Oh sorry, you meant him - not me ............. In the OP's defence he was probably working from a phone not a computer keyboard. Ok just went to the machine yes scavenge and trans pump were both changed cleaned out trans screens 20hrs ago no material or object in screens checked inlet pressure 105psi hi idle 3rd gear stall 95psi outlet pressure 55psi 3rd stall Hi idle machine is 2271 rpm stall is 1760 rpm machine has sat for a while i stalled in 3rd got trans to 120 degc and hi idled and dropped like a rock im getting machine hot and in working conditions and going to check cooler differences. Back to Stan's post #32 above regarding the link to the fluids recommendations........ Here is a snip from the D8N Maintenance Manual for this particular model of tractor. SAE 50 is not even mentioned, which actually surprised me, it usually is in there as an alternative........ SAE30 is good for ambient temperatures up to 40 DegC. IMHO that will be more than acceptable for the conditions under which this tractor operates. This comment ...... machine has sat for a while i stalled in 3rd got trans to 120 degc and hi idled and dropped like a rock ..... indicates to me that maybe the OP could have been right all along to be looking at the engine coolant circuit, but by God it's taken us 2 pages to get to that point.
sorry about the punctuation guys yes i was doing it on my phone at the machine ambient air temp for the day was 26degrees got machine in working operation trans at guage 110 coolant at guage 95 trans housing infa red gun at rear 84 trans cooler 97 top bottom 89 radiator 83 and 73 inlet pressure 105psi hi idle 85 psi 3rd stall outlet press 55psi stall it has a 82 deg thermostat in system ran machine for 1 min hi idle machine guages engine 90 trans 105 machine when working trans and coolant guages gradually creep up together gradually and because engine temp is 15 degrees difference all day it takes a while for trans to cool quickly
Before we rebuild this dozer from the ground up looking at the cheap bits first must be the way to go . I am taking for granted both guages are electric , not keen on both being electric even though they are tracking well together . Check that the temp guages are correct and that there is enough airflow going through the radiator , is not constrained by side panels or a nice thick coat of yellow paint on the radiator . Has there been damage to the exhaust system and constricting that , maybe even a sticky flap .What this dozer could have managed new might not suit it now . Have the injectors been serviced since new , are they putting out a mist or a blob (want of a better name ) of fuel .
Did you check tranny lube pressure?
Epirbalex
reading all that it should be working perfectly , problem is its not .
New temp sender and guage was fitted lube pressure in spec weve been driving machine for past couple of days with no engine side doors to see if its air flow am getting a cooler thermostat today and goin to fit
D8N used for dozing or ripping or pulling a implement? Like plow or disc?
I've not worked on 8N machines but I've done plenty of converters in H's and K's and the common heat causing failure is leakage through the stator, turbine and impeller. This can be seen by checking the scavenge output from the bottom of the converter housing. I think I saw where the converter was replaced so my question is was it replaced with new, exchanged rebuild or rebuilt in house?
another thing you can have a look at is your air cleaner , low flow through a turbo causes it to heat , heating oil , flow on effect .There would probably be more black smoke as well with this if it was the air cleaner . Having your dozer running at 1500 revs with no load and not cooling points to this .
Dust in a radiator core will keep heat in the core, might not be much trash in the core but dust can sit in there and cant be seen and will cause it to retain heat. Have been on a 10 T lately stripping topsoil, eng temp went up to 97c, not much much trash in radiator but washed it out with water and it now runs at 87c, so if u are in dusty conditions might pay to have a look. Cheers
8L--3408E, folded core radiator pulling 26ft wide drag scraper in 2nd gear leveling for AG, will heat trans-powertrain oil to 235f/113C / engine 210f/110C IF the radiator is not blown out daily. Dust accumulates in the areas outside of the fan radius. Ambient temperature 35-40C. TO4-30wt oil. No extra cooling capacity with standard radiators.
I know a fella who got sick of trying to hunt down overheating problem on a D4H , no single problem other than a lack of radiator capacity , he added another radiator in front of the existing one , problem solved . Accumulated age related problems all adding up.
transmission light came on today at 130 degrees celcius engine 110 took 10mins engine still only went down to 95 it just gradually goes up and only 8 degrees diference in radiator was thinking of degassing condensor and taking out and seeing if it improves, or should i put some sort of flush through the cooling system see if it gets any crud out
If available try Cat's radiator flush. I hook up a water hose to the bottom radiator drain and open the radiator fill to push the crap out of core and top tank with the engine running at idle speed. Then operate the machine again until the temp reaches just below 'red on the gauge' and reverse flush again until the coolant-water is no longer rusty. Loosen crap settles in the top tank and plugs the core tubes. OR just pull the radiator out and clean the core tubes. Old Cat oil dip stick and pressure washers works okay to 'rod-out' the core tubes.
If when you say "8 degrees" I assume you're referring to the difference in temperature between radiator inlet and outlet coolant temperatures (correct me if I'm wrong), and if so your radiator is absolute borderline on cooling performance - 12 degrees is the norm. Start by cleaning the cooling system internally - some good recommendations from Stan above. What coolant are you using BTW..?
A LOW differential temp across the radiator really only indicates one of two things, correct? Either plugged (internal or external) radiator, or too much flow? I know Burns has said the radiator, water pump, thermostat, and pulleys have been replaced, but is it possible the thermostat is faulty ?
Next time the transmission oil & filter gets changed put some SAE30 TO-4 in it....... Just thinking out loud but I wonder what temperature differences an infra-red thermometer might see when looking at the front of the radiator from left to right and top to bottom as the engine warms up from cold..? Thinking about it if there are plugged passages in the core it ought to be possible to see their location using an i-r gun just at about the time the thermostat opens. I know the OP said the radiator was replaced, but was it replaced with a new core, a re-core, or a complete radiator, and more importantly was whatever was replaced an OEM part or a “will fit”...?
radiator cores were replaced with cores from a dozer suplier here in aus, not genuine but new top and bottom radiator tanks were left in there and fitted new cores, it runs elc cat coolant in machine, another thermostat was fitted only two weeks ago on machine genuine
Short video of 3406B / 623B cooling system that was not using ELC. Green Glycol coolant did not look bad, machine wasn't overheating...I just wanted to clean out cooling system before sending the scraper to the desert with 30-40C ambient temps. AND demo for the machine owner and his mechanics explaining WHY Green Glycol based anti-freeze creates cooling system and internal engine damage (cavitation erosion > water pump failures, pitted liners, block damage etc). The solid particles (rusty crap) draining out of this coolant system was a eye opener for the machine owner and his mechanics. Agree with Nige, SAE50 TO-4 will create a bit more heat caused by increased pressure required to lock-up the frictions (steel-to-friction disc) per Cat engineers.
I like the current Ethylene Glycol based coolants vs Propylene Glycol as not so aggressive on systems yet still have doubts as to useful life and no system maintenance claims. PG tends to break down too quickly, what additive is used to make ELC different than straight Green EG.
Make sure someone didn’t install the fan backwards
I can only speak for my experience but we are using an ELC (not Cat) and it basically runs maintenance-free apart from SOS sampling for the life of the engine to overhaul which is 18,000 hours in the case of our haul trucks. Good point. I don't think anyone asked about that.
@burns Did the 8N have some type of ELC coolant when purchased? I am asking because Ethylene Glycol or Propylene Glycol based coolants that are not maintained can cause cylinder block liner ledge-to-liner sealing problems that allow combustion gases into the coolant system. The 'rubber filler band' just below the liner ledge hardens and coolant additive solids cause the filler band to wear away allowing coolant to contact the cyl block liner ledge interface. Symptoms; 45 minutes to a bit over 1 hour of dozing or ripping and the trans-torque heats up and takes 10-15 minute @ high idle in neutral to cool down. Machines act like the torque is flooding causing overheating issues.
I've not seen any problems with standard coolant when changed on the manufacturer's recommended schedule. That usually means replacing it every two years or as indicated by analysis. I've seen plenty of rotten systems with brown colored standard coolants that have been used for more than five years and witnessed the cost of failed components. On the other hand I've seen plenty of machines with the Cat ELC installed for more than six years that showed no solder bloom in the radiator and the operator / mechanics didn't remember ever adding coolant. The stuff is more expensive but well worth the cost in my experience. There is also a light green stuff I've seen being used in the automotive industry that is in my wife's 4Runner that has never been changed since we bought the car. That's at least ten years ago. I'm all for ELC.
Standard coolants versus NOT following OEM's recommended schedule or NOT READING OEM's maintenance manuals. Using straight glycol anti-freeze as make up coolant means increasing additive solids. I get really pi$$ed having to spend 8-10hrs removing built up crap inside of cylinder block cooling jackets before machining counterbores, upper inserts or repairing head bolt threads. 3408-3412s with cavitation erosion caused block cracks; no fun welding up with N55. ELC works as advertised and eliminates 'crap shoot' as to waters' chemical, biological make up etc.
ambient air temp today was 40degc removed 50w oil and replaced with cat tdto 30w, cleaned radiator, with very little dust in it. put to work pushing loose dirt within 0.5 hr engine was up to 100deg transmission 115 deg put machine in neutral @ high idle in 10mins engine went to 85 transmission 100 when machine was at hi idle front radiator doors were open i put a ray temp gun on top tank and bottom tank, there was 100 deg top tank 88deg bottom cooling fan pushes out threw the radiator hense why i took engine bay doors off my transmission and engine temp raise together and fall together, im confused as to which is making the other one hot
operator can work in the morning for 4 hrs and it just gradually creeps up, he cools it for 15 mins gets temp to 85 engine 100 trans once hot it takes half and hour to get back up to hi temps again of 105 engine 120 transmission
12 degrees difference between top tank and bottom tank is spot on what it should be. The thermostat should be controlling the temp around 88-90 so it will be fully open at 88 for the return coolant. See post #58 on P3. Is the fan facing the right way..? And before you ask - reversing the fan will not make it suck air from the front and push it out the engine bay. But having a fan installed "backwards" can severely reduce the air flow through the radiator. Post a photo if you're not sure if it's installed correctly or not. It's another box to tick.
I don't Know about D8Ns but does it have the reversible style fan like older ones? If it does are all the blades facing the same direction? If some are pushing and some are pulling it will mess up your cooling. If its a fixed style fan disregard last transmission. LOL
That one brings back a memory! Had a guy who at the time was the "road mechanic" for the shop back when I was the new kid and he tried like hell to convince me and others that would work to reverse the flow of air for the winter! To try to explain why to others over the years why it will not work I always used the analogy of the fan being a very short piece of all thread and the air was the nut. If you always turned the end of the all thread facing you clockwise no matter which end of the all thread faced you the nut always moved in the same direction! As for the fan running backwards not moving enough air ask a pilot if he thinks a plane would fly with the wings facing the opposite way?
Does this photo make sense
Looks right to me. Engine turns CCW when viewed from the rear, the knife edge of the blade would be leading. We're running out of ideas, bud.
I think it is capacity of the cooling system . Every thing has been replaced , and the one thing is that it does not cool enough when not working to carry on . I have already said what a fella did here with a D4H after trying to sort this problem . He told me Goughs ,Caterpillar NZ agents , had a good look at what he had done . Another , all be it stop gap , windscreen washer motor and jets can be added to jet water through the radiator every now and then , if putting another radiator in front of the current one is not an option . Caterpillar would not have designed too much redundency into the system nor I doubt build it to be working nearly forty years later flat out .
Tough to say without being there, sometimes it’s tough enough when you are there. From the sound of it, the T/C is putting a lot of heat into the cooling system. That tells me that the T/C is sending plenty of oil flow going to the cooler, not leaking to the scavenge pump. I’m pretty sure if the clearance between the impeller/stator/turbine are too wide it can cause a drastic loss of efficiency in the T/C, and extra heat. The O/P says the T/C was rebuilt, could be that parts were reused that shouldn’t have been. The radiator can do a good job of cooling the coolant, but just before it enters the engine it goes through that big ass transmission oil cooler. I’ve shot dozer transmission cases with my I/R in the Arizona afternoon after shift and seen 200F. Just an idea.
yeah its tough one im going to get a friend with experience to give me a hand with a few different thoughts. t/c was a rebuild from tillys, one operator in qld says his machine wouldnt go past 90deg engine and 110 on trans its a long way off that. im only using a infa red gun im thinking i need to borrow correct temp guages to guage exact differences between coolers, radiators, oil pipes transmission and engine. whats really hard is this machine has done it since he bought it 18 months ago, and i havent got any past service history.
3406Bs temps @ 91.1-92.2C (196-198F) are normal with T-stat opening 90C (194F) Tilly's family owned non-dealer; inquire if their T/C rebuild-exchange has a warranty. If your friend has Cat 8T5300 injection timing meter, check inj timing also. Governor has wear parts that can cause heating issues. Without machine's past service history can add to diagnostic challenges.
one thing i did the other week was check timing just pin timing but it was correct not to say governor has issues
That photo shows a sandblast guard. What kind of tubes do you have in that radiator. Are they the big copper tubes that can unplug from the tanks? Or is it more like the older radiators with the small tubes?
i not sure what you mean, they are on angles fine fins and to fit them you need tolift top tank up
I recall years ago a core they called a desert cooler that had big round copper tubes instead of the smaller tubes with the small strips of metal fins that always got bent over on fan side on the left side of the machine. There were fins on the large tubes but not nearly as many fins but it looked like lots of surface area for air to cross over on the front of the radiator. The only issue that I heard with those units was that you had to have a sand blast guard on the fan side to prevent the sand and debris from wearing through the tubes. The larger fins were also suppose to let debris go though the core without getting trapped. I saw one used in a landfill. It still packed up but with big stuff. It took a lot longer for the broken dry wall fibers to plug the thing up.
Mesabi (L&M Radiator) is in Western Australia with exchange radiators. Using individually replaceable cores like Cat. http://www.mesabi.com.au/coolcats.html
T/C rebuild from Tillys is waving a big red flag.
Can someone here who has actually rebuilt a Cat torque converter/divider please explain how it is actually physically possible to assemble one incorrectly? They are possibly the easiest powertrain component to build and are basically just a stack-up of round things and thrust bearings. From memory, the only thing to easily get wrong is the sprag clutch and this machine doesn't have one. The OP stated that his outlet pressure and lube pressure are within spec, so that in my estimation eliminates the sealing rings as a source of trouble. As far as I'm concerned, an incorrectly built TQ will either lock up on the assembly bench or make metal within seconds of starting. I'm genuinely curious to hear other opinions on this. Back to Nige's cooler theory.
Been down this road with aftermarket parts. Didnt want to spend the 2k for the cat rear hub and mainshaft, it leaked internally like crazy after it warmed up. Lifting the hub out the ears broke off and upon inspection found that the metal was extremely soft where the sealing rings grooved the run surface in a short amount of time. The hub was also machined out of square resulting in a minute wobble.
If the seal carrier grooves are roughed up from prior usage with gritty oil or a after market seal carrier is used that has 'non-OEM surface finish and material hardness' the seals will wear out quickly and cause flooding. That won't show up by checking outlet or lube pressures. Two bushings to install to spec'd depth. Oven heating aluminum hub to 300deg F to install parts and freezing bearing race cups. Basically simple to build torque dividers. 657 torque converter support carrier bearing 1T645, finished tolerance after machining 4.5045" +/- 0.0005". A grin to install, roll-burnish into the carrier's groove and finish machine to spec'd tolerance; Cat does not leave much extra material for finish machining. Timken bearings, they're not all the same and rated by class for run out tolerances and mounting surface tolerances. I won't touch non-OEM parts for trans or torque dividers including oil-coolers. Simple math; if the parts cause problems I have to eat the labor and parts' cost to replace with genuine etc. Plus pi$$ed off customers. Non OEM oil coolers. Bigger tubes but fewer to reduce manufacturing costs. You end up with less surface area to transfer heat out the bundle into the jack coolant system.
What I’m talking about is the running clearances between the wheels and stator. If the bearings are worn, the impeller/turbine will rub and wear against each other and the stator. If the builder re uses the wheels with new bearings the clearances will be excessive. THIS WONT CAUSE LEAKAGE TO THE CASE/ SCAVENGE PUMP. The Hot oil will go to the cooler and lube circuit but can eventually overwhelm the cooling system. Cat gives a procedure to measure these clearances in the assembly manual. You use steel balls and a dial indicator. The wheels need to run very close to each other to be efficient.
The problem I’ve seen with poorly built jobber parts in a torque is that the tolerances between the impeller stator and turbine are not right. The oil still goes out through the outlet relief with no internal leakage but the efficiency of the converter is lost. The converter is a fluid coupler and high clearance makes the coupler slip. Much like a water pump with an eroded backing plate. This slippage generates more heat. Also on the d8n when they first went into production we had complaints of them running pretty warm on trans temps. They found the coolers were undersized for the machine and later machines and d8r came with a larger trans cooler.
At the point where we are right now my money would be on a less-than-perfect rebuild of the torque converter.
Later torque-divider equipped machines' service manuals no longer show or mention the procedure using steel balls and dial indicator to measure and check Stator-Turbine / Stator-Impeller clearances / *running clearances. Current procedure; use inside micrometer and measure across the diameters @ two points / 90 degrees spacing and compare to service manual's specifications chart. Minimum / Maximum diameter as specified / *Running Clearances = 1/2 measured diameter. T/C problem? IMO, most probable.
if we are thinking the t/c wouldnt my stall specs be wrong creating slip and generating more heat, does anyone know what t/c temp should be generated from inlet to outlet side, i know it depends on conditions but there should be some general temp obviously queenslander youve had issues with tillys
Tough call, could have low engine power and weak converter combining to stall speed in spec! As for temperature readings, think about the latent heat of boiling water. Once water hits 100C, no matter how much you turn up the fire, the water will never get hotter than 100C. The cooling system is absorbing the heat, and your operator stops the machine before it redlines. Probably the only sure fire way to confirm a bad T/C is disassemble and measure. The fact it takes so long to cool off tells me it’s probably the power train. That whole rear housing where the ripper mounts is probably 200F by days end.
Hi, some questions please Has the engine oil cooler been looked at, as it is series with the transmission oil cooler it will effect cooling ability Has the correct radiator been fitted. if it is the folded core type with a/con it should have 12 cores.no air con fitted it will have 8 cores plus there are a number of conversions available as well check out SEBD1963 Also if the coolers are clear lower the T/C outlet pressure to low end of spec
ambient air temp dropped quite a lot today it was 30 deg c the operator told me that the engine did not get above 90deg but the transmisson got to 120, he let it cool at high idle and it took a good 15mins to get the trans down to 100deg. this there fore seems the transmission is thee one generating the heat but i think that the cooler should cool system down a lot more, correct me if im wrong but i think i should look into getting a new cooler
A new cooler would certainly be cheaper than digging into the converter again, that’s for sure. Whether it fixes the problem or not remains to be seen.
I really think cooler is doing its job if the coolant temp redlines at the same time the transmission temp redlines and it cold off so slowly. But keep in mind that “we all” are giving free, long distance advice.
When they are running it to cool down make sure its revved up a bit like 1200 rpm. That increases cooler flow.
By the sounds of post #93 above they are running it a High Idle in neutral in an attempt to cool the power train, unless I'm misunderstanding.
@ burns Consider Re-checking T/C outlet psi @ high idle, 3rd gear @ stall now with 30W trans oil. Ref: your reply #34 T/C out 55psi, high idle, 3rd gear @ stall with 50W trans oil. R&I Trans oil cooler: Check current oil cooler tubes for sediment, crap by using a rod pushed threw each tube. Good window as to the coolant system cleanliness.
Sorry I missed that. Most people will let it sit at idle so I thought I’d mention it.
yes operator is having machine running at 1500 when cooling down, that was my next step was to check pressures with 30w in it now. when i had the cooler removed i did rod all coolant lines, the operator did tell me that origionally before i was involved it did have a green coolant in it, but he put a flush threw it, when i changed t/c a month ago i had those tubes off and inspected them, i also checked trans screen when i c/o oil to 30w
What exactly is the tractor doing? Dozing, up hill down hill ect. ?plowing? Bob
Bob, last week dozing loose dirt with 40C ambient temp @burns , Check trans-lube pressure also to have a reference point. T/C outlet valve: If your pressure is lower with 30W use 5M9623 spacers and raiser the pressure to 65-70psi. 1ea spacer increases psi 16.5kPa (2.4psi) Spacer thickness 0.90mm (0.035")
No, I haven’t had issues with Tilly’s personally. It might be a little unfair, but I’ve just formed an opinion based on experiences of others over the last twenty+ years. Most of it stems from problems associated with the non genuine parts they sell/use but that is to be expected to some degree. I went to school with the proprietor and can vouch for his integrity.. at least I could back then .
Bloody unfair to put this on Tillys , I have seen at least 2 hightrack 8's sold with new radiators in NZ , a very small market . This dozer could well have been having this problem for years with the last owner pulling the pin on it . I can only wonder why it had 50 grade oil in it , was it a stich up to sell it . The problem is lack of cooling capacity , and if its not addressed soon enough damage will be done with the current owner making the same decision as the last , to sell it . Caterpillar paring the last pound of copper from the raditor should be taking the blame , not Tilly's .
We had elevated, but not excessive tc temps prior to R/H steering clutch failure. (Piston seal gave way once piston over-extended, loosing pressure. point being it wasn’t preceded by excessive clutch material in the screen) After repairing both sides with new clutch plates / friction discs, we run very cool T/C temps. Does the machine seem slow to respond when clutching? Low probability but perhaps the whole rear end and trans oil are so hot it takes a long time to cool everything down. Apologies if this was addressed earlier. Cheers
[QUOTE="Mark250, post: 785659, member: 50833"Has the correct radiator been fitted. if it is the folded core type with a/con it should have 12 cores.no air con fitted it will have 8 cores plus there are a number of conversions available as well check out SEBD1963 [/QUOTE] Good comment on the folded radiator Mark. I worked for a contractor that had about 15 new D8N's. Probably more than that ,I don't remember the exact number. None of them had AC. All of them had open ROPS. All the folded radiators were replaced within a year with conversions to the flat style. The folded ones were plagued with hard to see leaks on the bottom of them. They leaked again even after being repaired.
Correct me if I'm wrong, but isn't this a differential steer tractor..?
D8Ns are diff steer. Mark's SEBC1963? SIS DVDs-Dec 2017 shows baffles for marine engine coolant tanks to prevent foaming? Repower engines have 92-DEG-C T-stats, illegal to swap out with lower opening temp T-stat... On-highway 3406Bs...T-stat 190-210F (88-99C), Top tank normal 206-208F (97-08C) very good system 196-198F (91-92C) Fan Clutch temp switch ON @ 205F Injection Pin-Timing (field timing) is used to set static timing to start engines, then timing is set with meter-timing to check or adjust gov start point. 3406B Aluminum T-stat housing where the T-stat seals @ bottom can erode allowing a bit of coolant to recirculate instead all coolant flowing through the radiator. Cat 4C-4611 90 minute quick flush will not remove hardened, baked on solids on the interior cylinder block surfaces or inside of cylinder head in 90 minutes. I would pull off one oil cooler bonnet and peek inside of the cyl block. Exchange T/C did not resolve the problem. Maybe a bit of improvement? Ditto switching to 30W power train oil. Sounds like lack of radiator cooling capacity, but the machine has run for 32yrs with original folded core radiator, 8 core or 12 core?
correct its got diff steer, 12 folded core in radiator thermostat i put in the other day was a 1209453 it did have a 2485513 in it
248-5513 is a heavy-duty temperature regulator fully open at 92 DegC. 120-9453 is also heavy duty, but with a fully open rating of 82 DegC. Going to the regulator with the lower opening temp might stave off overheating for a while, but I'm not sure that it's a long-term fix.
2484413 is 92-DEG-C (198F) blah ha, Nige is to fast for me. Probably already checked, are the air bleed vent lines open?
Stan, The document Mark referred to was SEB1963, not SEBC. Copy attached.
D8N Diff steer peek-a-boo / left side of video
stanrus what do you mean by that
Just for the guys who have not seen inside of a 8N,R,T case and diff steering.
Don't DEE 8's have a little hose from the thermostat back up to the radiator to bleed the air out of the system ? System full of air won't be good . May have been removed with all the work done on the dozer .
Lines = 2, T-stat housing and Trans Cooler vent (air bleed) lines to prevent air-lock and entrained air in the coolant system. OP can also ditch anti-freeze if the machine's location doesn't have -0Cdeg or -32Fdeg temps for extended periods. And use purified-neutralized water with Cats' corrosion inhibitor; corrosion inhibitor prevents rust, corrosion, liner-block pitting and lubricates the water pump seal faces. Water-Inhibitor coolant will transfer heat out the system quicker, lowering operating temp. Band-aid, but the machine can operate a bit longer before stopping to cool down.
Stan, There's actually a product available now called ELI (Extended Life Inhibitor) that is designed for locations where freeze protection is not required but is otherwise of a similar formulation to ELC.
on the engine coolant have anyone done a water bottle test over the pressure releif hose? ive seen a 3406 moter stays runs hot and no heat in the cab after putting new themostat, water pump, heater core, radiator, lines etc. and on the transmission can you post a video when you walk around with the laser tempature gun i ask this becuase if you are hitting something round you will get incorrect readings vs something flat n flush
was trying to sourse a thermometer group went to nearest cat dealer im wanting a 4c6500 but theyve been discontinued, any one out there got similar temp group that i can chase up to purchase, im not real happy with the infra red temp gun want to plug guages in and work machine and see whats happening
4C-6500 has been replaced by the 368-9910 Multi-Tool. It has loads of different attachments, but you want the 308-7267 Digital Thermometer Group. I'll warn you before you start, they will be pricey....
4C-6500 Ebay $249.00 FOR PARTS ONLY - NOT WORKING https://www.ebay.com/p/NOS-Genuine-Caterpillar-4C6500-Thermometer-Group-Tool-With-Case/1304435750