I am looking to buy a 1984 Cat 931 with an engine serial of 45V31446 and trans number 1AA01241. I believe this year had the 4 cyl diesel so I wanted to verify if someone had a way of looking this engine serial up for me? The owner said the machine does not have blowby common with the 4 cyl but he didnt know alot about the unit as he too used it for farm clearing which is also my plan. Tank clearing and push cedar\juniper and moving small piles for burning. No issues with the machine although hour meter didnt work 3 years ago when he got it but since put one on and put 120 hours on it over 3 years. Starts right up no leaks and only issue is the left track needs periodic tightening which is done when he greases it to tension. 16k for the machine and this is my first dozer type machine although I run skid loaders and tractors. I plan to use for a few years and sell once my work is done as well.
If it helps the machine serial is 29Y1109 Thank you for the help in advance. Based on what I have seen the price seems inline with others if not lower for my area.
It's a 931B and they're a good little traxcavator. 29Y1109 makes it a 1981 year of build, by my book. The engine is a 3204 direct injection model and the 45V31446 engine serial number is for a 3204DI, and appears to be correct for the machine. They only used 2 ring pistons from the factory, this is a "low-friction" design, but most owners rebuild them at overhaul with the later 3 ring pistons. $16K sounds about right for a 931B in good operating condition with good undercarriage. No leaks is good. Sounds like the track tensioner seals need replacing. Post some photos and we can likely give you more pointers. The condition of the undercarriage is what primarily governs the value of a tracked machine.
OzDozer posted while I was typing. I don't have my serial number book handy but my 1st thought is it's older than 1984. First thing to check is the undercarriage. If the engine is original and hasn't been worked on 3204's are known to have more blow-by due to only using 2 piston rings. It sounds like the left track adjuster needs new seals but the shaft could also be rusted. You could see if the tension release bolt might be a little loose. How does it steer? Should only need light toe pressure.
Thank you both for taking the time to respond and share your experience. I go next weekend to view and possibly purchase this machine. He has been really good to work with.
Overall it looks pretty good except for missing windows and doors. Not a bad machine if you wanted to clear some bush. The undercarriage has been worked on/replaced and improved by changing the sprocket hub to use bolt on segments. It doesn't have the sprocket counterweights but that's not a big deal. The pads are from a dozer but not really high grousers so should be fine. Tall dozer grousers are hard on a loader because they put extra stress when turning. Dozers don't turn near as much as loaders. Rails look to have good height but hard to tell if the rollers are hitting the pin bosses. Marks could be from small rocks or something hitting the pin bosses inside the rock guards. Speaking of the rock guards, unless you're working in lots of rocks it's best to remove the rock guards. They just trap dirt and mud and can contribute to increased track wear. Can't see the condition of the bottom rollers or the bushings on the rails. Judging by the sprockets and rail height I think the bushings are likely in good shape. It doesn't look too abused. Sheet metal looks pretty straight and it has the engine side shields which aren't bent and dented. A bunch of hoses were replaced too. 16K seems reasonable if the transmission and steering/brakes work properly. Can you run it for 30 minutes or more to see how it runs at operating temp.? It looks like a decent machine.
That's a very nice little tractor that shows it's been looked after, and not abused. If only mine looked that good! It'd be interesting to find the reason why the owner installed dozer track shoes on it. You have to find the reason for the hit marks on the pin bosses. The track chains are in excellent shape, but if the track rollers weren't replaced when the track chains were, then the roller flanges will be hitting the pin bosses, and that's not good. Roller flanges hitting pin bosses makes the track pins fall out, eventually - and the rollers will be near the end of their life and be liable to fail. When the rollers get worn out, the seals fail, all the oil runs out, and then the roller is toast. The marks on the pin bosses may be caused by a track guard - but even so, the reason must be found, and the problem fixed. Track guiding guards are good to keep trash out of the track rollers and chain, but if working in deep mud, the mud gets in and can't get out, it block up the tracks, so better to take them off. Don't forget to check the bucket cutting edge and the underside of the bucket. These are constant wear areas, and they need to be kept in good shape. If the track rollers are good, the tractor is certainly worth $16K. Check that the serial number tag on the engine matches the number on the loader tower. The tag is located on the rear upper LHS of the engine block, up near the head gasket.
I can’t say enough about how I appreciate you both providing some fantastic information. Once the deal is done I will share a couple more details that should contribute to this being a good deal. I have a good list of what to check and will be asking. Although he didn’t have the machine much throughout its life he knew that the machine was not abused. With that said the historical reasoning for things may never be know but I will ask. I don’t know much about flanges or rollers but I am going to make sure I research it more so I can develop an eye to help me understand what to look for and provide good updates here. I am excited to have this old machine which to your points does seem to be in relatively good shape.
What’s funny is there is a JD 455g 91 model for 22k with 3k original hours and is much closer but I am still drawn to this older Cat. The JD looks good but has a slow right turn until warm and starting to get a leaky cylinder.
The JD is probably less abused work wise over its life as the first owner used it to move mobile homes apparently and the current owner only did a few odd jobs and hasn’t put 100 hours on it. I just don’t think the maintenance has been as good as the Cat despite the information but I will at least look at it although the Cat seems to align better. 22k for the JD
That 931B cutting edge is in reasonable shape, but some hardfacing on it wouldn't go astray. Plus, the wear level on the underside is important. There are wear plates on the underside that need to be kept in good shape. A good book to acquire if you can find one, is an older Cat Custom Track Service Handbook - especially one around the year of your tractor. They are a goldmine of valuable track care, track maintenance, and track repair advice. Plus they have specs for wear in there. 1982 CAT Caterpillar Custom Track Service Handbook 8 tractor manual D4 D3 D6 D8 | eBay Find many great new & used options and get the best deals for 1982 CAT Caterpillar Custom Track Service Handbook 8 tractor manual D4 D3 D6 D8 at the best online prices at eBay! www.ebay.com.au The Cat is a better buy than the JD. Around here JD products don't have the same level of resaleability as a Cat.
Huge Thank you again!
You can get bolt on teeth adapters and teeth or bolt on cutting edge segments for the bucket. They both use the same holes that are on the existing bucket. The bolt on edges come in 3 pieces, center and 2 ends and are reversible. I think they're 8" wide, maybe 10" so will last a long time. I have both but took the smooth edge off because I found my skid steer is better for finishing things like the jump faces on my MX track. I'd recommend teeth for general purpose work and digging. A smooth edge is good for loose material and finish back blading. You'll just wear the bucket edge out the way it is. If you go with teeth I can't tell if your bucket has holes on the side for corner guard teeth where the adapter straddles either side of the bucket side plates and uses 1 big bolt through the side plate. These style teeth save the front corner of the side plates. I've heard the JD G series are pretty good machines. The 455 in the pic. looks to have lever steering which would be a hindrance for loader work. Pedal steer lets you have 1 hand on the bucket control and 1 hand on the trans. or throttle at all times. The JD has wet steering clutches and brakes. It may just need adjusting but could be more serious if it's slow to respond until warm on only 1 side. With 3000 hours it will probably need undercarriage in 1000 hours or so. In small track loaders I'm not sure if there's a lot of difference in resale between Cat and JD. The JD is 10 years newer and track loaders are similar to skid steers. If they still work they come down to a certain price and stay there unless they're in really poor shape. It might be good to check on parts availability on the JD. Cat generally has much better support for older machines although some say it's not as good as it used to be.
Thank you Welder Dave I would be really interested in getting teeth for the bucket as I also have a skidloader its a SV340 and I have a nice smooth and also toothed bucket for it and also know it will be much better for finish work. This Cat would be used for digging holes pushing juniper over and pushing piles of it around and loading piles into a dump trailer. I also have a limestone hill which I hope to query some dirt and such from. I will keep this thread going once the purchase is done so I can work towards getting some teeth.
I will be getting that book as soon as the purchase is completed. Big thank you for sharing and I hope to find other manuals and such so I can stay on top of it all and keep this machine looking and performing well.
Both of you made good comments related to the pin bosses. So yesterday I had a chance to see the machine, drive it and make a deal. Zero blow by and transmission and engine wise it passed with flying colors. All fluids were perfectly clear minus the engine oil which was just starting to darken from recent service. Its not perfect and I have my work cutout for me but I think it is all manageable for the price. I paid 15k. Now for the work. I have to get all gauges working since a few dont although engine temp alternator and couple others do. The shift linkage is loose so needs to be brought into spec. I bought the CAT 931B book and the specs book and confirmed it needed adjustment. So related to those pins rubbing I believe I figured it out. The right side did not rub but showed the pin marks (old marks) you both saw because I bet it was rubbing and someone fixed the track issues on that side. The left did rub because the adjuster seal seems to need to be changed and before adding grease to tighten the track I ran it and confirmed the (fresh marks) rub. The owner said the tracks on the left take about a week and loose tension again although not totally slack. ANy feedback welcome if I am crazy on this thought. The risk to this purchase is I believe the next item. It seems you have to fully push the brake pedals to get it to turn quickly but I "HOPE" its also an adjustment issue. If not I may be dealing with some clutches.... For 15k I decided to take the challenge on given she functioned well on brakes and slow when partially depressed. Because I have the manual I will be able to diagnose more on how out of spec it is once its delivered this coming Friday. The smooth bucket has holes for teeth already so I am going to try to measure the spacing as it has 2 holes per tooth so I can try to figure out what teeth this bucket seemed to have on it before as I want to make this a toothed bucket ASAP. More to come on this crazy adventure but I am excited and believe I can handle whats ahead of me.
You might be able to get aftermarket teeth adapters and teeth that bolt right on. Does the machine come to a stop if you push both left and right pedals half way down at the same time? If so it means your steering clutches are OK. In the other recent 931B thread I explained the easy way how to adjust the brakes.
I pushed the middle pedal to bring it to a stop, so I didnt try that but I absolutely will. And I will find your thread you are referencing for certain. I hope its just some adjusting ......
Yes when I pushed them down the machine did come to a stop. Also when I push either pedals the machines turns on full brakes. The machine does not turn when you partially push in a pedal. I believe it is supposed too but not as sharply? Also can you guys point me in the right directions for parts? Is CAT the place to go? So far I dont need much. The most important thing I need is a track adjuster seal kit as I did pull the rock covers and power wash everything and tried to tension the left track. It tensioned to a point and then grease came past the seal and rolling out so this is an immediate fix needed. Any help on where to begin the parts search would be great.
Outside of adjusting the track steering and fixing the track adjuster seals I need the following additionally. Seat cover of some sort. Extra set of keys for master and main teeth for the bucket I ran the machine basically forward and back doing a little practice but being mindful of the tensioner issue and was able to confirm all gauges work and machine runs with zero issues. Someone spent some money on her given she has zero black smoke. Starts immediately up. Transmission is perfect minus the steering adjustments needed. All fluids are spotless minus engine which is clearish and starting to go black like it should from a recent oil change. Lots of work on the family land. The old house in the background. Powerwash after taking the rock covers off. Lots of dirt that had decided to basically become concrete but eventually cleared out.
Please post photos of the keys you have for confirmation that they are "standard" Cat keys. Take a look on the back side of the bucket, up top RH side. There should be a data plate in that location with the bucket Part Number on it which should identify the correct teeth. See the illustration below, it's the small rectangular plate to the right of the decal marked #21. If there is no plate take a look for a Part Number stamped in that location. Do you have manuals for it yet, espcially the Operation & Maintenance.? IIRC you were asking in another thread.
Hi there Nige yes I was able to purchase the full CAT manual as well as the track service handbook. This is great information on how to identify the correct teeth. I really appreciate it. As far as the keys go they do look original but to your point I will get a picture when I am back out there in a couple weeks. The keys both looks basically like this.
Your keys are Cat P/N 8H-5306. Aftermarket versions are available. You should have asked. I could have emailed you an electronic pdf copy of the Custom Track Service Handbook for free.
Thank you for the part number Nige I will get those ordered ASAP as well. I sure like having the hard copy but certainly would like the PDF version. I am learning alot about this machine. I love how simple it is although one heavy beast LOL.
It falls into the category of what would be regarded as "Lawns & Gardens" equipment........ I still fail to understand how anyone larger than a dwarf can work on a machine that small.
Ha ha ha well thankfully I am a little rascal so I can get into the tight spaces but geeeze its all heavy ha ha ha...... It will certainly be an adventure but so far so good. Your comments are true and amusing.
One of my former work colleagues always opined "If you can't walk underneath it then it's not worth working on....."
It sounds like your steering and brakes work properly. Pushing half way down let's that side free roll so it can gradually turn a little bit. It won't do any abrupt turn unless you apply the brake on that side. A fencing staple will work for a key in a pinch. I'm curious why you need 2 keys on the machine? Track adjuster seals might be available aftermarket but shouldn't be too expensive from Cat. Would be good to also get rid of the rock guards. They're more trouble than they're worth. You don't normally need to remove the covers for the recoil springs but if you're fixing the adjuster seal they need to come off.
I am currently on the hunt for the seal kit. Looks like I will just have to call CAT and order from them direct I guess. I wanted a backup set of keys because mine look "weak". I did take the rock guards off on both sides now. Here I am cleaning it up. Once I get the seal kit it should be fairly easy to change from what I have read.
You have to split the tracks. Hopefully you have split master links and the bolts come out OK. Make sure to put anti-seize on them when you put them back in. Release the track adjusters first.
I watched some videos where you do not have to split the tracks to do this. I am not sure if that will be my case but we shall see.
I wanted to update this thread that I was able to fix my track adjusters with the help of a few friends. I did tack the track off to do the job because there was a welded on bolt to prevent the roller from sliding back and the tension being released. I left the bolt since it was pretty far back but now know it would have been an easier job had I ground the bolt off. Lesson learned. Since then I have gotten some hours on the dozer and she runs wonderfully minus I do notice some brake adjustments are needed. When I press the brakes to slowly turn it I seem to have to pump or the turn is ever so gradual. When I push the brakes to the floor They better be all the way down hard. I have the manual so I will be tackling this next weekend. In addition a few of you recommended some procedures which I will also take into account. Last but not least I will start measuring my running gear as I do hear a pop from the tracks so I suspect its time for some parts especially after trying to set tension and I lost a track on the other side from my track tensioner repair. Got the track back on fairly easily and tightened the track more and pops are reduced. Oh well seems to never end. Pops happen on 180 turns and not always.
I didn't look back through earlier posts but my thoughts would be to inspect/repair/lubricate/adjust the external control linkages first before moving forward.
Some great points... I have done this as part of my first inspection of the machine. I even had to replace the return spring for the left brake so the pedal would not stick. It seems the brakes may be just out of adjustment from how it is behaving. I will check the current adjustments from where the manual recommends and adjust accordingly. My fingers are crossed its somewhat simple.
TBH I would recommend that first you disassemble the linkage completely (without doing anything to change the adjustment) then clean & lubricate each component. Unfortunately because of its location under the floor that linkage gets badly affected by dirt and contamination.
I didnt disassemble it but did lubricate and checked for any kind of binding. I also broke loose all the locking nuts and they all came free without issue. I will have some additional help this weekend so I can take it further if needed. The nice thing about this machine is I have no real rust or dirt caking. Its a very clean machine. Even when I took the pads off when doing the track work they all broke loose with minimal effort. I have been surprised thus far.
If anyone has suggestions on how to address the seat with new foam\cover or to replace it I would be open to ideas. Its the biggest eyesore on the machine.
I'd put a new seat on from a place like Ultra seats. They are reasonably priced and you can even get covers to protect them. They are much cheaper than getting a seat from Grammer or Sears seats. My machine has a backhoe and uses a flip over seat so I had to get a new wooden seat base made with foam and covering. Thankfully I found a good upholstery shop to do it. I put a new Ultra seat with arm rests in the grader for about $400cad.
Thank you Dave I will check them out...ok I am checking them out and wow lots of seats to wade through.