I have a 1970 Cat 951 that has been sitting inside since 1998 waiting on me to get the nerve up to rebuild the transmission. I'm now at a point of either tackling this project or scrapping the machine. Engine starts easily and does not smoke, loader with 4 in 1 bucket raises and lowers fine, and there are very few leaks. When I parked the machine, 2nd gear was out forward and reverse, but everything else worked fine. Now, there is no movement and I'm not sure where to start. Anybody out there have experience with transmission removal and rebuild? From the manuals, it looks like bottom removal is the best alternative. Any guidance would be most appreciated. Are there any free lance mechanics out there in the Northern Delaware area that might like to either help me or tackle this project?
First thing to get a better idea of what this machine is can you supply a S/N? At least the prefix? Quick check on SIS showed about 7 different prefixes. Prefix is the first part of the S/N like 59H, 69H..... But being a 1970 machine might not even be in SIS, but if you have manuals just go one page at a time! I did look at a 32F model and it looks similar to say a 966C transmission but with out the drop box. First thing before pulling it would be to drain oil and remove filter and inspect for metal or other junk. Also remove and check the suction screen for junk. If you have the operators manual it should be listed in the 1,000 hour service section.
The only number I found was on the engine and it is an 86J 1491 Type B. Is there a separate chassis serial number? If so, where is it located? I have not drained the transmission, but the oil on the dipstick was completely clear.
According to me you have a 951B. I think that it is an earlier model with a D300-series engine where the machine Serial Number is the same as that of the engine. Only on later models where the engine model changed to a 3304 did the engine have its own separate Serial Number. To start looking at the transmission you need to be removing the suction screen that is found at the bottom of the transmission case. If you have a burned up clutch then this screen will have major quantities of friction material in it. To get at the screen I'm fairly sure you will need the belly guards (or at least one section) removed.
951B makes sense. The machine has 951B decals on one side and 951C on the other. I did not really know which it was, and the guy I bought it from knew even less. I bought service manuals from the local Cat dealer based on the serial number, so hopefully, I have a reliable guide. I assume that to pull the screen, I need to drain the oil. I'll have to get under the machine to see what I need to remove. Next step is to curl up with the service and parts manuals, so I have some idea what to do. I'll be back for more guidance once I get the screen out.
Okay 86J is showing up on my SIS. And to removed the strainer book does say to drain oil first. Screen is on the front side of the oil pan 6--3/8 inch bolts. Post picture of what you see there.
And whatever you do don't throw that material away. We might want other photos of it.
OK Will post photos and keep the remains for potential forensic studies. First order of business is to find a pan large enough to hold the transmission fluid. My Lubrication and Maintenance Guide lists the capacity as 10 gallons. It also has pictures of the pieces that need to be removed, so I have a real good idea of what needs to be done. Thanks to all for your help so far.
No worries. If there is anything you're not sure about don't go blundering along blindly and potentially screw something up - ASK...!
Don't junk the tractor. You have the makings of a fine long-term project and a useful and valuable machine. Just one small bite at a time will do it. Regards, Clark
Thanks for the support. A very good friend calls it "moving the peanut forward", and I guess that's where I'm at. Looks like this might get to be a long thread before I'm done. I'll post some pix as soon as I can get all the stored junk off of it. 18 years is a long time to sit around.LOL
And don't worry about the money we have no problems spending your money! Actually I'm hoping if anything we can offer you advice that may save you some of those "Pictures of Dead Presidents"! If or when it comes time to disassemble the transmission have a box of zippy bags and a couple marker pens to help keep small parts in groups to make identifying them easier.
There are quite a few classic track loader threads on the forum. Opinions of other HEF members may differ but IMHO you should grab yourself a bog of popcorn, get comfortable on the sofa, and work your way through this lot ..... HeavyEquipmentForums HeavyEquipmentForums
Wish I had some spare time. I only live in Jersey and wouldn't mind helping with that project.
Zbo2 It's good to know there is someone close by. Any help or advice is greatly appreciated.
Personally if it moved before I would try and get it moving again. Then I would begin troubleshooting pressures to be sure there is an actual problem that requires an overhaul. Either way removing the strainer is probably the first step.
DB2, I am confused on that issue. When I parked the machine in the late 90s, I drove it in. First and third both worked in both directions, but 2nd gear never worked. Now, nothing works. When I bought the machine, several "experts" told me that there were a ton of orings in these transmissions and I probably had some failed Orings. If that is the case, perhaps the others died over time. If not, who knows. My plan is to get to the strainer, see what it tells me, and go from there. I think troubleshooting pressures is a likely next step. I hate to waste 10 gallons to do the test, but I guess it's all for a good cause. Would I learn anything from a chemical test on the old oil (when I get it out)?
Don't have to "waste" the oil just take a little extra time cleaning around the drain plug and have some clean pails to catch the oil in. Could also put a fine screen on top of the buckets to grab any crap that might come out with the oil. Also could strain the oil through some cheese cloth before putting it back in, or maybe a paint strainer? The oil pump has to suck the oil through the screen so it is possible that it has been plugged from sitting all these years causing too much restriction for the pump. I do think checking the screen would be the best place to start, if it is full of clutch facing no need to spend time trying to check pressures. If it is nice and clean then we can start trouble shooting the problem.
Coffee machine paper filters work well. A bit slow for large quantities of oil but as ksh points out there is no need to waste it if you are careful. The time to dump the oil would be if the results of diagnositc tests shows the need for the transmission to come out.
Well, I think I have figured out how to catch the 10 +/- gallons of oil. When in doubt, buy another toy. I bought a 2.3 gallon evacuator that pulls the oil thru the diptube. I figured it would take awhile, but would not be a mess. I have pulled about a gallon so far, and based on the speed of extraction, I think the oil is as thick as coal tar. It's pretty cold here, so that could be a contributor. It's coming out, so that is all that matters.
My old Allis has a early powershift trans with as stated a lot of ring type seals that are probably failing from its massive years of service, I swapped transmissions from a donor to keep it running while I looked to rebuilding the original unit to which it has set in the barn for darn near to a year. I promise myself every time I see it to get it up to the shop for tear down. Everything on my old beast is weak, hydraulic pumps, seals, brake/steering controls so I need to invest some real time in it. Good luck on getting yours moving again. Miller
Years ago we bought a IH 175 (I think that's the model) crawler loader. It was running and working when it was parked in a small garage. After sitting for 15 years it started but didn't move. So the old operator hops on, revs the engine and starts dropping the bucket to jolt the machine. Well it then took off I have no Idea how it didn't go through the wall!
It's good to know that I'm not the only one in this boat. I will try to catalog my journey here so we can all get a good laugh or two!!! Now it's off to put a heater under the transmission so I can empty it. With cold oil (high 30s here), it will probably take forever to vacuum pump it out.
You can run the engine, right..? Even though with your issue you can't stall the torque converter to heat up the transmission oil rapidly the oil will warm up if you get the engine up to temperature.
Thanks Nige, that makes sense. I got sidetracked today with some sandblasting, so I did not get to try the heater under the transmission. I do have a question rearding access to the strainer. My lubrication guide shows how to remove it. In the first picture, it says to remove the round cover in the middle of the bottom pan and drain the oil. In the next picture it shows removing the strainer cover, but the bottom pan has been removed. Do I have to remove the bottom pan to access the strainer? The pan looks to be very heavy and the machine is on a dirt floor, so a floor jack won't do me much good. I'll try warming the engine tomorrow.
The way I read it they remove the guard/belly pan in picture 1 above, then remove drain plug in picture 2 and then the cover with the strainer in the picture 3. They are NOT removing the oil pan from the transmission. That cover with the strainer attached looks to be the same one they used on other machines, like the 769C haul trucks I worked on. The picture is not real clear, but I'm guessing that the belly pan does have an access cover that you can remove to drain the oil with out dropping the complete belly pan. But to get access to the strainer the belly pan will need to come off, or hinge down if it is made like some. Just be careful as it may be heavy with a lot of dirt! The pictures might be a little confusing as picture #2 looks like a brand new machine and is taken from a little different point of view and #3 picture looks like a well worked machine and a bit different view and lighting. But to answer your question do not remove the oil pan!
kshansen, Thanks for the clarification. I did not state it well, but was pretty sure that the Transmission pan did not need to be removed. I am mostly concerned about that belly pan. It looks like a beast to remove and even more fun to put back on. I will consult my parts manual for (hopefully) a better picture. This will really complicate getting to the strainer!!! May have to get the steel weight calculator to figure out if a plywood support plate will support a floor jack to drop this plate.
Steel is roughly 500 lbs/cubic foot, or roughly 40 lbs per "board foot" (12" x 12" x 1") if that helps any.
And like I said you need to understand that if the belly pan is full of oil and water soaked dirt the weight of the steel might only be a fraction of the total. So never position yourself under the belly pan, or in a place where if the jack was to slid out of position the jack could hit you.
I used a car style rolling jack on a sheet of 1/8" steel and cribbing on top under my belly pans to drop them. Getting them back on the jack was a little more problematic laying under the machine and rolling them side to side to get up on more blocking to get the jack back under them for reinstall. As a side note, IF you can get the tractor to move at all, drop the loader bucket elsewhere leaving the arms light and set them on either blocking or blocked up on the machine for better access from BOTH ends, fighting the bucket AND the low height is a lot more than I care to do again(lesson learned).
Thanks for the notes. I am planning to use a floor jack as DMiller suggested, but don't have any steel plates. I am hoping that a 3/4 inch sheet of plywood will take the weight. I'm guessing the belly pan alone weighs at least 90 pounds and the oil soaked dirt will add another 50 min. Regarding dropping the bucket off - not so easy as this has a multi-purpose bucket, so I would have to disconnect hydraulics as well. I'm not planning to reinstall the belly pan until the trans if working properly. When all is OK, I will be able to put the machine up on blocks on a concrete floor, which should be a lot easier than playing in the dirt. Either way - a formidable task awaits.
I use a transmission jack to remove and replace he belly on my 977L, works great because you can adjust the level at each corner, you can rent them if need be.
Great idea! I happen to have a transmission jack - just have to find it!!!
I know that feeling, usually the biggest part of the search is trying to remember who borrowed it and then who borrowed it from them.
Nige, your idea of running the engine worked like a champ. The transmission oil got warm after about 20 minutes of high idle, and then it all came out quickly. I got 5+ gallons out thru the diptube. RBMcCloskey, I found my transmission jack and tried to use it, but it was too tall, so I just used the floor jack. Turns out that 1/2 inch plywood was more than enough to support the load and it was not as bad as I was expecting. Belly pan is out and the rest of the transmission oil is draining from the drain plug. Got too cold and dark to continue - will hopefully resume tomorrow. The Belly pan was bent upwards in the middle and partially crushed one of the tubes. Wonder if I will be able to find one of these used or have to fix it somehow.
Anytime you can get the pans off is a good time, been a lot of good machines go up in smoke from fires in there they could not extinguish from all the debris and oils.
Well that might answer one question I had, if oil got warm I'm thinking the pump was circulating it, so pump maybe good. Still interested to see what might be in that screen. If screen and filter both look good then next step would be to look into doing some pressure checks. You, have the service manual I believe so do some reading to see where test ports are located and what pressures you should have. If not sure let us know and we will look into it.
Some time ago, I read about pressure checks and realized that I don't have any appropriate gauges, so I stopped on that. I will have to locate the proper gauges as I'm sure I will need them at some point. You make a good point about the pump. However, since 2nd gear has always been out (I bought it that way), the trans will eventually have to come out. I was just hoping to get it running long enough to get in the shop and up on blocks. It's much easier to use the loader to elevate the machine than using bottle jacks. Next stop - strainer removal.
Well, I think I will definitely be dropping the transmission given what I just found. Here are a few pix of the strainer and miscellaneous parts found with it. Anybody know what these were part of?
If those pieces in the last photo are metal (as they appear to be) then they are most likely the remains of a steel separator plate that goes between two friction plates in one of the clutches. God only knows where the bits of spring are from unless it's somewhere in the control valve.......there are no springs in the planetary transmission itself. Do you have a Parts Book..? because it looks as though you are going to need one............
Nige, I do have a parts book, but there are no exploded views - only cross sections that make it hard to determine what is what. I also have a Service manual with lots of pictures of transmission removal and disassembly. They show at least 10 small springs located between clutch plate packs. I'm going to hazard a guess that the 2nd gear clutch pack exploded which is why my 2nd gear doesn't work in either direction. The big question now is why did 1st and 3rd gears stop working just from letting it sit for around 19 years? Since I ran it for 15 or 20 hours back in the late 90's, I assume that the damage did not affect the other gears and parts were caught in the strainer. I have not removed the filter yet, so it will probably tell another story. Does anyone think that cleaning the strainer and filter will allow 1st and 3rd to start working again? I only need to drive it about 50 feet to get it in my new shop, so I can do a proper repair. I don't have anything else around here large enough to push or pull this baby into the shop.
Some of the stuff in the strainer looks like river sand. Hopefully you can get it out and find out the issues without being out a ton of money.
Correct what I said before, there are springs (10 x 9H-5537) in the planetary transmisison. From the appearance of the screen it looks to me as though the complete transmission hydraulic system including the cooler is going to have to be pulled apart and cleaned in addition to rebuilding the transmission. If even one grain of that sand gets where it shouldn't all your good work rebuilding the tranny will be for nought. With the transmission in the state it appears to be in I wouldn't even consider trying to move the machine under its own power. Can you not beg/borrow/rent/steal something that will drag it for you..? While I think of it - Offroad Equipment www.offroadeq.com/ are a good source of parts for machines such as yours.
Dickjr and Nige, The pictures may be a bit misleading. There is no sand that I can find - just a lot of rusted steel granules. The oil was milky, which indicates water. Perhaps sitting 19 years on a dirt floor may have contributed. The brown particles are rusted steel (I think). I plan to put the whole thing in an ultrasonic cleaner with Ozzyjuice so I can retrieve all the particles for further scrutiny. Now that I know that the trans must come out, this project will move to second in line behind finishing my shop. Floor is poured, but not cured, walls need to be built and air HVAC installed. Then I will have an air conditioned space to tackle this project. Nige, thanks for the parts lead. I think I will have lots of parts to search for. Thanks to all who have helped so far. I'll be back!!!
Don't be a stranger.......
Not a chance. Too much good info on this forum.
We will all be awaiting word of outcome. Dave
Dave, I know I'll be back. Just started cleaning the strainer and surfing for used transmissions and or parts. Will a newer transmission fit this machine? I'm not seeing any 1970 vintage units.
I know you are half a nation away but there are a great deal of tractor salvage companies out there. Try Machinery Trader for the parts search section, if you can get a search against a s/n value of your machine they may be able to come up with something. One big help I have had is General Gear in Idaho, and yes I realize the shipping costs would be GINOURMOUS but could be worth it if they have a unit there.
DMiller, thanks for the leads. I will follow up on both.
I just did a search on Machinery Trader and they list my transmission part number (4S8686) as fitting a Cat D4D. Would these two transmissions possibly have the same transmission? Thanks for any help on this. My machine Serial number is 86J 1491
Have you confirmed your transmission part number (4S-8686) by reading the data plate on the transmission itself or from the Parts Manual..? The former is the most reliable method. The 4S-8686 transmission fits the following models - 941, 941B, D4D, 951B, & 951C. According to my information there have been 22 different iterations (known as Change Levels) of 4S-8686 over the years. When rebuilding a 4S-8686 you have to know which Change Level you have because some internal parts will change from one Change Level to the next. However if you are looking to replace a complete transmission with another one then it should not matter whether the two of them are the same Change Level or not, one should be a direct replacement for the other. A word of caution. If you remove your transmission and overhaul it you will know at the end of the process exactly what you have because you've been inside it yourself and know exactly what condition it's in. Buy a used component (even from a seller who has the best of intentions) and you have no idea about the internal condition, you simply know that it is the correct Part Number for your machine.
Nige, I am using the parts manual as a reference right now. Do you know where the data plate is? Mine is all covered with more than one coat of paint and lots of dust, so it's like looking for a needle in a haystack. Regarding used parts condition, I totally agree. However, thinking about the history of the machine, the previous owner bought it for one job and the trans was already hosed when he got it. That means it may have run 100s of hours with the damage I found. Given that, there may be too much damage to repair on this one. I am just hedging bets by looking for a used one. I also have to get some ideas of what the basic clutch packs will cost. Any ideas of a typical clutch or backing plate cost? There are about 17 in my machine. I also had another thought regarding why this machine will not move. It seems like I have torque converter problems, in addition to the apparent trans problems. Any thoughts on this?
Nige, Just found a fully rebuilt trans with 1 year warranty, but it's above my current budget. $5000 exchange. I may not be able to afford to rebuild this baby, if parts are that expensive. Oh well, it only hurts for a little while. Have a great day!!
The plate with the transmission S/N (if it's still there) will be mounted on the transmission case just below the top cover. I think on that transmission it is on the LH side. To give you an idea the 3S-7981 discs are listed at $50 each. The 3P-8393 Plates are $135 each. Those prices are for genuine Cat parts, I'm sure that Offroad (and others) will be able to offer you all sorts of options at much less than that. I found 3S-7981 available aftermarket on the internet for $13 each. If it moved in all the gears except 2nd when it was parked up I see no reason to indicate that there is a torque converter problem. It may need cleaning and some new seals/gaskets (remember it shares the same oil as the transmission) but that ought to be it.
From that picture of the strainer every part of the system will need to be removed and cleaned. I would say oil cooler should be replaced with new or remaned one, too hard to clean. Planetaries all disassembled and inspected. I would think all bearings would be in need of replacement along with all seals, and orings. Running the part number for the cooler through NPR it starts as a 9M8039 then goes to a 7N0128 and the Classic Part Number is 2991994 and the Cat price for that is about $262.00. For that price I could not see myself taking a chance on getting a used one 100% clean. To me getting it out and on the floor could be hardest part of the job not knowing what you have to work with. Just a quick look at the cut-away in parts book it looks much like other Cat transmissions of that vintage. Maybe lots of parts but overall easy if you work in a orderly fashion. And as for the cut-away pictures, I prefer them very much over "exploded views". It's surprising how much information you can see in them once you get used to them. Cat is very good about having things to scale so you can see if part 23 will fit through the hole in part 26 and such. If you want another place to contact about a used transmission I would give this place a call, they are just a small local outfit near me but they do work on a lot of the older Cat equipment and they have a bunch of old machines in the yard. S & S Tractor Parts Inc OPEN 7:00 am - 4:30 pm 2500 Station Ln, Marcellus, NY 13108 (315) 673-1075 Ask for Mark
Thanks guys. WOW!!! What a wealth of information. And I thought I was going away for awhile.LOL I see now that I have several homework assignments. I found a used transmission that has been disassembled, inspected and reassembled for $3500, but it requires a core. So, anything I do requires waiting on my new shop. I guess I had better get to it. Any suggestions on a good paint? As long as I have to tear everything down, I may as well sandblast and paint everything along the way (which may make this a really long project)
Regarding paint, go back to one of my earlier posts where I pointed you in the direction of a couple of classic track loader threads. Nitelite painted his machine and made a really good job of it. Lots of "how-to" painting tips on there....
Nige, started on the threads (read about 10 pages), and got sidetracked removing the belly pan. Will go back and read these threads. Thanks again.
I would hope that they reassembled with new gaskets seals and orings. Still keep in mind that all hoses, steel lines and fittings will still need to be cleaned extremely well and the oil cooler that is mounted on the engine should be replaced, I would not even think about trying to flush it out. $262.00 saved could cost you a $3,500.00 transmission not to mention the labor involved in removing and installing the transmission.
kshansen, I did not get very much info on the used transmission, as I am not able to buy anything until I get my transmission out and they want a core. I did pay attention to your suggestion and actually found several aftermarket OEM replacement oil coolers priced from 125 to 250 depending on seller. Also, I figure that if I can get the transmission out, I should be able to rebuild it with help from the wizards on this forum. Since I have a Parker Hose crimper, I may replace all the flexible lines and will definitely clean all the hard lines. You know the saying - anything worth doing is worth Over-doing!!!
If you decide to sandblast your tractor, be very careful to seal the mechanical systems from the abrasive. You may find that a good cleaning with a steam cleaner will do the job prior to painting. Most Cat dealers offer a good deal on high quality paint. Regards, Clark
sealark37 Thanks for the tips. In my experience, Hot water pressure washing and steam cleaning do a great job on grease, but not so good on multiple layers of flaking paint and rusty bare metal. It has been nearly impossible for me to get a quality job without sandblasting to bare metal. I agree that mechanical systems need to be sealed prior to sandblasting, but I am more concerned about protecting the cylinder rams. It only takes one slip to turn a shiny ram into a seal shredder. At any rate, sandblasting will not be a trivial task on a machine of this size and complexity. The last time I used Cat paint (early 90s) it did not want to dry. I assume that they have improved the paint and will check with them on recommendations. I'll be at the dealer next week and will check.
It's quite probable that no-one at the dealer will be able to make recommendations about what's the best process for painting a machine from that era. If it was me I'd do exactly what Nitelite did in his thread. See here (Page 46 of the thread if the link doesn't come out right) ...... HeavyEquipmentForums
Nige, Thanks for the link, it worked quite well. Nitelite took his machine down much further than I plan to take mine. Great looking paint job too. In his description, he mentioned cutting the paint with acetone. This is an improvement over what I used in the 90s, so it may dry better. I use a gravity gun versus a conventional gun, but everything else is pretty much the same. I did some surfing last night and found sources of plates and disks as you mentioned. Looks like I'll be able to source the major parts quite reasonably.
To further save your hard-earned $ there MAY (and I say that advisedly) be a gasket and seal kit for the transmission. I looked on Cat's system and didn't find one but that does not mean that an aftermarket supplier doesn't make one. To buy everything in one box is usually much cheaper than buying every Part Number separately.
This is definitely worth a shot. What did we do before the Internet???
I looked on SIS under "Kits" and there is a listing for the "Transmission Overhaul" it comes up as 154-5681. Problem is when I tried checking availability it comes up as "Indirect Replacement" "See Dealer" . Which generally means discontinued order individual parts. It as shows up with a list of the individual parts and doing a quick check on them total price come to about $707.00 But if you do a google search for "1545681 Cat" it comes up with a couple aftermarket sources and price listed on a couple are in the $100.00 range. No idea of the quality or completeness of them but something to check out.
kshansen, Where did you get the 154-5681 number? I registered with Empire Cat's SIS web portal (not a paying subscriber) and was unable to come up with a cross to the 4S8686 transmission. I saw the SIS reference in other posts but did not know what it was. I assume that you have a different subscription, as I did not get the "Indirect Replacement", only "See Dealer".
kshansen, Just got back from the local Cat dealer and they confirmed your kit number and printed out the list of included parts. They also confirmed that the kit is no longer available. Nige, regarding paint, not such a good story. It seems that Delaware Cat dealers no longer sell solvent based paints. - only water based. I bought one gallon to experiment, but have not had good experience overall with water based paints. I know all the mfgrs use it, but they bake their finishes, so it's a totally different animal. Has anyone had experience with the Caterpillar Water Based products?
You could also look online for 9S-1073 which was the Gasket Kit that was replaced by 154-5681. Some aftermarket sellers will surely still be offering the kit under the old Part Number.
Well I used the S/N 86J01491 to do my search. Once I'm logged on and opened to the "Main Menu" Down near the lower right corner it says "Kits Information" red arrow in the following: When I click on that it opens a box where I can enter numbers like S/N of the machine or engine or arrangement Also note there is a selection to search by kit number. It appears that you have to use the last good kit number but you can find that by searching in NPR that is right above the "Kits Information" on my screen. Not sure if your's is set up the same way, as I know some features are different depending on what a dealer has activated for you. I'm still using the access I had at work and they have not turned it off yet for me, and I retired a year ago!
I'll check but am betting that you have full access that would cost me over $700/yr. I'll rely on your intel as it seems to be absolute!!! Thank you!!!!!!!!!!!!!!!!!!!!!!!!!
Caveman, try what Ken suggested above and when the Kits Information box opens up simply enter your machine Serial Number and then hit the Search button on the line below. A list of every kit available for that machine should appear.
Nige and kshansen, I finally to the screen shown above. I was actually on the wrong site - at a dealer offered parts web page. After getting past the CWS login, I was directed to the actual system. Thanks much - very valuable resource!!
To get to the right place without going through the parts page you need to go to https://sis.cat.com - that will take you direct to the CWS login screen
That is the one I found this morning. It's got a wealth of info. Thanks again for the tip.
Hello Again! I can't believe it's been almost 5 years since my last post. As I mentioned, this project was way down on my list, but I didn't think it would take this long. Too many fun life events got in the way, and my shop is not completely done even now. However, I need to move the Cat project machine to pour concrete, so it moved back up on the list. I recently found a used transmission at a reasonable price and am considering it so I could minimize the shop time. If I can rebuild this one, I can swap it with the bad one, hopefully without disappearing in time warp again. My question is this: how often do torque converters go bad, given that I have had metal parts coursing thru my oil system? Thanks again to all the people that have been helping me with this project.
Congratulations on enjoying your life first! If that transmission is cheap enough I would rebuild it first and switch it out. If you need major parts you could pull your old one out and hopefully you can steal what ever you need. Sorry I don’t have the skills to help with the rebuild, But if you do it, please post pictures along the way for some of us that would like to see your progress. I would add find a clean place to do the internal work. Also covering up your work when your done for the day is a good habit is a good habit. Best of luck!
Main concerns of torque converters is bearings, bearing play any internal contact indicating said slop or bearings failing then clearances to provide adequate fluid coupling. Too tight risk contact and self destruction too loose and fluid cooking from excess heat. Beyond that just typical seals and cleaning.
Cat977 and DMiller, thanks for the comments. I checked with the donor transmission owner, and the torque converter is included, so I guess I'll have another component to rebuild.
IMHO definitely worth going into the converter, have a look at the bearings & replace as required, fit all new rotating seals to the shaft(s), finally all new lip seals & gaskets throughout.
Nige, Nice to hear from you again. I am glad that the torque converter is included and will definitely include this in the rebuild. Thanks for the support.
The Transmissions in 951B/C's are not hard to tackle but you will need the Tractor up on blocks to get it out, the B Series is not the same as the C, the pinion for the bevel gear is a different tooth count to start, not many O rings to worry about but it looks like your gear carrier is scrap. tctractors
Tctractors, thanks for the input. So given your assessment, it sounds like getting this used transmission is the right move. The donor machine is also from a 951B, so I should be OK. If, for some reason, the bevel gears don't match, can I swap them?
The 951C has a different tooth count on the Pinion & Bevel also on the F/Drive Pinion and Bull Gear 9 x 52 on C's, 10 X 58 on B's. tctractors.
TcTractors, Thanks for the clarification. The full serial number plate on my machine is missing and the only ID that I have is the Engine mounted Plate. I think I have a 951B but can't confirm it. One question. Can I take the pinion from my old transmission and install it on the replacement transmission, assuming the replacement transmission gear is different?
By the S/N 86J1491 on that engine plate (provided it is original) you have a 951B. 951C models started at 86J1992 and the 3304 engine update did not come until 86J2598.
Thanks Nige. How do you identify the engine model (other than the S/N plate). One person said that the older engines have 4 bolts in the center of the valve cover. Here is a bad picture of mine.
Older machines with the D300-series engine the Engine Serial Number is the same as the tractor Serial Number, or at least it was when the tractor originally left the factory. Later machines 86J2598-Up with a 3304 engine the Serial Number will be totally different to that of the tractor. 3304 engines installed in a 951 machine will have Serial Numbers that start with 78P.
The earlier 330C engine is the same bore and stroke as the later 3304 series, the simplest way to tell is via the water pump, who ever came up with the 4 bolt thing is way off, the 951B has a vented cowl, a fuse box on the right hand side, a Trombone style bucket level control, front grill plates fully hole punched with no un punched margin top and bottom, water cooled transmission oil, exhaust muffler above the bonnet, the original track pitch is 6"3/4,I could go on, I suggest a Parts and Service book would be a wise investment, the changes are so many even the R/H bucket tip cylinder rod has a keyed control arm on it, so the r/h rod is a different part number to the left rod.
Tctractors WOW!!! I now have lots of things to check on my machine. I will report back on the items you listed. This is kind of like getting a pet DNA test to find out what your pet really is!!! I do have all the manuals that Caterpillar offered in the late 90s, but they are a bit intimidating to just sit down and read. I will be studying them now as i get closer to picking up wrenches. Thank you very much for the extremely detailed response. I am absolutely certain I will need your expertise many times on this journey.
This week, I actually moved the peanut forward a little bit. I found a used transmission and torque converter, and got it home. Here is a picture of the S/N plate and the purchased package. I also bought a ROPS cage as mine did not have one, and I thought it might be a nice upgrade. I discussed the transmission rebuild with the guy I bought it from, and he only suggested going thru the torque converter and checking the spline connections. He checked the oil and did not think it was burned, but I will have to evaluate the oil and filter before I make any decisions. Comments on whether to rebuild or not are certainly welcome. I guess it also depends on how much trouble I have getting the trans out. The transmission looks like it has been painted, so it may already have been rebuilt (it looks much newer than the torque converter). Happy Easter to all!
Nice to catch up on this thread. Caveman,it might be an idea to pull your old tranny apart at the same time as you strip and evaluate the new one. tctractors has done this for me before with D8 transmissions. He makes it look easy,but he knows what’s reusable and what’s scrap.It’s harder to call if you’re a novice. Eitherway it’s good to have them both apart at the same time (but keep them totally seperate).
Nicky 68a, Thanks for the suggestion. Good idea. I was kind of hoping to minimize the time in the shop by prepping the transmission in advance. Since I have a "maybe good" transmission, I was not planning to tear into mine until later, but I may have to rethink this strategy. As you can see from the time delays in this thread, I don't do things at "light-speed". My problem would be not knowing what was good or bad in either transmission. I am also concerned that I would get both apart and not understand the nuances of putting them back together, and end up with two junk transmissions.
Yes,I see your point Caveman As for forgetting how it all goes together,I think these chaps on here will steer you in the right direction for sure. Having both trannies stripped will also help you compare identical parts between the old one and the new one. You’ll only need that one carrier or any other gear or a shaft etc that will make you happy that you stripped both trannies down.
I'm sure you are right, but there is a lot of trepidation here. By the time I get the loader in the shop, hopefully I'll have conquered the fear of breaking them both. How far down would you suggest? Open up to the carrier level, or full breakdown?
I would just see how easy it is to get the bad one out first. Then go looking at how deep and comfortable you are at tear down time. You may want to replace some outer seals and go.
The transmission is not hard to tackle and most often a reseal plus a few bearings and thrust washers will sort things, the torque has a habit of bearing drama so fit new bearings to it, the spline drive coupling can shear and twist so check it well, on the B Series the build date is stamped on the R/Hand Hard Bar under the frame guards/covers, on the C Series its often stamped on the l/H and loader frame by the light mount. tctractors