1941 cat d7 can it be brought back to life?

Cloudaway

New User
Central PA.. I was told this caught fire at one point and was parked. Can anyone tell from looking at this, offer opinions. We may be talking about being parked in 1960. Near as I can tell it is around 1941 d7. There is a video on YouTube of one and it looks identical to me. Thanks for any insight.
 
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It could, don't get me wrong, you'll be investing quite a bit of time and money. It would take me a while to respond about the many things you'll want to look at on this tractor in the idle state it's been in for how many years.

1st thing you'll want to do is see if the engine is stuck, see if it turns over by moving the fan, if the belts are still intact. I'm not sure what that has for a clutch housing cover if it is a 7M series, and where in there you could get a bar on it to turn it over, you need to get to where the starting engine pinion engages it.

On the crankshaft pulley or end facing the radiator, there is a way to fit a steel rod with a dowel through it to mate up with the nut on it. Using a pipe wrench or if you have a hexagonal or flat surface machined in, a wrench may work with a big cheater bar, but if you need that cheater, it's stuck. I have been through that on one of these that looks similar, still have it and another in much better shape.

Look on the engine towards the back, and or on the back of the tractor, left side, above the final drive housing, see if you can find a serial number, if 1941, it's a 7M series, next series up would be 3T, and 4T which was a gov't purchase order of 10,000 units. There are some 6T's out there too, bought for the US Navy, and even more scarce are 1T's that were armored.

The starting engine needs to be checked out, see if seized. You'll want to really look over the undercarriage, at a glance it is well worn, but my oldest one is just as worn, your pads look better and I see what looks like a loose pad on yours. If it is worn out, I hate to say it, might want to pass. I like these old tractors and it's a nice thought to see someone bring one back, but can be a money pit, or you may luck out. I'd also want to make sure the heads are not cracked on the engine. These are notorious for sitting and being brought back, but if the engine is seized, you'll need to do some work to free it up at minimum.

The dozer kit is not LeTourneau, at least the radiator guard and front mast, + overhead ridge beam for the power control unit, (cable winch - these are not towing winches either).

Hopefully it does not end up as scrap, they are a handy tractor even today if operational. There are more things to check, want to make sure the sprockets are tight to the shaft, and that the final drives are good, minus the seals, those may leak a little by now, the bellows seals in these.


I'm all for going for it, but realize that is a lot easier said than done LOL !

I can refer to my manuals if you do need help , but you'll want yourself a set of those for this tractor if you decide to embark on it. Serviceman's reference book, parts catalog, and operators instructions + whatever may be available for the power control unit, (cable winch for the blade)
 

Thank you for the response. I looked in the front of the engine for just a moment the other day and I remember seeing slots on the front of the crankshaft where a bar could be inserted and turned. I don t remember seeing any belts, but I need to go back and take some more photos. This is sentimental to some extent, I am 37 now and I have played on it my entire life. I remember when I was a kid the slats over the roof were in much better shape. I probably slid the hood off who knows when.... I will get better pictures when I can as it s parked near my parents house. I live about 30 minutes from it, but it s out of the way of my normal drive. I really appreciate your response. Thank you.
 
Anything to help, there are some resources out there like the antique caterpillar machinery owners club and similar, you can find parts for these and so on.

I would reset that hood and make sure the exhaust stack is covered, looks like it is now. On the right side, there is, towards the front, lower of the engine an hour meter, just flip up the cover if you are curious to see the hours on it. I don't see much evidence from what can be seen it caught fire, but I can't see the left side of the engine. There is a small gasoline fuel tank for the starting engine, unless it was converted to direct electric start.

These are considered pretty durable, well built machines, they have a dry type clutch, later ones had an oil bath type which last a lot longer, but both were of the "bullet proof" kind of reputation. I did see olive drab paint under the yellow, on the injector lines, no doubt it is likely a military or gov't purchased tractor. If that diesel is not seized up, you've got a good chance with a lot of up front work to see it will run. I would be checking this thing over thoroughly, hopefully no one vandalized it. The books on it will be very helpful.

You'll want to check out the fuel tanks, drain out water, starting engine fuel tanks often get a build up of coffee grind size rust and plug the carb screen, these like good fuel supply and hot spark, the magneto needs to be in good shape to fire that engine. Carb is easy to clean on these, old cast iron Zenith carburetor. This tractor holds lots of oil in various compartments, you'll likely have a lot of condensation water to contend with. Coolant system also holds quite a bit, hopefully nothing froze up in the water jackets and cracked those heads, that can happen on these and the heads might be not so easy to find today.
 
You are anticipating an experience similar to a journey I started in 1990.

I was 30 at the time. I bought a 40 acre place to live that happened to have a D7 parked under a hickory tree. Of course I wanted it. I fabricated uses for it in my head so I could convince my wife we needed it. It was in better shape than the one in your pictures. It too had sentimental value to me. In early life it was military issue, then bought by our local school district to clear for a new football field. Then sold on auction again to a local farmer. So I bought it AND a 1940 something KB7 International semi with a Martin low-boy trailer. The truck ran but I did not want it. Sadly, the owner would only sell them as a package deal. I bit for 10,000 bucks.

So I started working on the Cat. The engine was loose so I tried to start the pony. It ran but poorly. I found the magneto was 180 degrees out of time. After that fix it ran good but I still step away when I rev it to full throttle because it sounds like it could throw a rod. I tried to start the diesel but nothing. Found the rack was stuck in the injection pump. That was an easy fix, it came to life.

I found that the oil cooler was leaking. I could not find a place that would fix the cooler. I did find a new cooler in California and it probably cost me more than the Cat was worth.

I serviced the tractor. It took the better of a week in my spare time after work.

YEE-HA now I get to use it !! It was fun, I was on cloud nine. I cut the dam on a small pond I wanted gone. Took all summer to get the muck out of the pond so I could fill it back in. I only got stuck once. Then I tried pushing some trees. What a surprise, those trees are pretty tough. They don't just push over if they are bigger than six inches.

I guess in looking back and looking at your situation, I would not do what you are thinking about. I wish I would have passed on the deal I did. Just be aware that if you go for it, you have a huge job ahead.

Think about it..... you're 37 now and haven't pulled the trigger yet. Are you trying to tell yourself something?
 
It may have been mentioned already but I did not see any comments below about tracks.

That vintage of track link pins were not sealed and are very susceptible to serious rust seizure from setting for a long time. If so, it may not roll sufficiently to get it winched onto a truck. It might be costly to get the pins freed up.

Even so, I hope someone will take on the project of bringing your sentimental D7 back to life. We have an old D7 (3T?) in our family with the cable lift that still runs but rarely used.
 
If the engine and pony motor are not seized and the transmission and clutch housing are not full of water and frozen and cracked the housing, you have a good chance of getting it going. If you can get a good size machine or a couple of big tractors , you can tug it and maybe free up the tracks. I freed one up that had been sitting 30 years, tugged it with 2 good sized tractors, a little bit one way then a little the other way until it moved a track length Hopefully you have a cap on the fuel tank . that would save a lot of work, if there is a cap and fuel in the tank, you might have to treat the tank with biocide, but there are a lot of other things to consider before than. I have a 1944 4t D7 that runs and operates that I need to sell, located in MA.
good luck.
 
If the crankshaft will turn any amount, I would suggest you don't turn it more that than a small amount about 5 degrees before you remove the valve covers and check for stuck valves. this might prevent the push rods or rocker arms from getting bent or busted.

Will the owner allow you to work on it where it is? If you have to buy it first, would you soon have to move it? I would think there would not be a problem with checking if the engine is stuck.

I think the track shoes are probably good enough to play with--- unless you want to work it hard.
 
Can't really tell from the pictures but it appears the radiator, fan and water pump are missing. If so, replacing those will add to the repair cost. Others have posted good points to consider.

Yes, it would be nice to bring it back to life. But think hard on undertaking this one, set the sentiment aside. It really won't be worth much, if any, more than now if you get part way through it and decide you can't finish. The money and time you put into it will be gone.
 
The dozer is accessible where It sits on my brother's property. I understand it may be a big undertaking. There is a good possibility it may sit for another 15 years until I retire. This forum is full of very knowledgeable people and I really appreciate the responses. From research I've seen several D7's and 8s listed on the web and on FB Marketplace in running condition and much better shape than ours for anywhere from 11k to 20k. I'm guessing that is what my cost would be to bring this back to life.
 
You won't really have an idea of how much $$ until you get into it. I would not let it sit that much longer, at least go and assess what you can, see where you'll need to start.

You can operate the compression release lever, that will open/close valves, can't recall if all, but when closed has to be enough given the timing, to get compression to fire the engine and run. I believe these are the pre-combustion chamber injectors, and there is a way to get penetration oil into the cylinders through them after removal if I recall. Never had to do that. Of course, if there is water on top of the pistons, won't do much good anyways.

At that point the heads will need to be removed to see what is seized, they are heavy, you'll need a way to hoist them. Don't do this and leave it that way, wait until you can follow through until it can be fully repaired.

I've got one in similar shape, believe it to be seized and I have not done much with it, but it's got sentimental value at minimum, at some point after I get the newer one operational again, I'll start dealing with it. This other one has just over 1000 original hours, it shows very little wear, track adjusters have never even been used. In the interim, I periodically turn the motor over by hand, check the cover on the stack and so on. The engine turns over with ease by pushing the fan blades. The starting engine, just use the hand crank to turn it over.

One thing to remember if you get this far, is that if you get the starting engine running, it shares the coolant system with the diesel and that diesel needs to spin to cool it. You can run in short periods, but don't over do it. Also, they are notorious or it's very possible to thin the starting engine crankcase oil with gasoline. I had it happen once, it overflowed the crankcase. Somehow through the carb. You'll always want to check the condition of that oil, make sure it's not thinned, or the motor will fail if you run it. The drain plugs in the bottom of the sumps are not so easy to get to. I have after cleaning all around the motor, the track, anywhere there is loose dirt or contaminants, removed the inspection cover and used a drill pump to suck out all the oil from each sump. This is also another way to see if the diesel is stuck, disengage the 2 speed transmission clutch, use care to engage it into low speed, they can grind if the clutch break is not working, then engage the clutch, see if it will kill the engine or it will spin the diesel. Compression lever must be all the way down, on "Off" which will allow the least resistance to turn the diesel. You need the operators instructions to read to understand the starting procedure correctly. Main transmission in neutral, Johnson bar ( Fwd/Rev.) lever in neutral, and master clutch all the way forward, though I think if engaged, trans is interlocked out, so it cannot engage, I prefer the master clutch to be disengaged to know the drive train is not connected.
 
The virus is giving me some cabin fever even though I am 81 years old and retired. I need to cut back on local travel to avoid the virus. I have some time to be boring!! LOL

I also have a sentimental attachment to old D7s. In the early 50s as a kid growing up, a contractor showed up in our farming neighborhood with his D7 about twice a year to do work in Ag fields. I always found time to "run a mile" and watch it work. Many years later, this early experience with the D7 had a major influence in causing me to choose Cat for my Engineering career.

I ask the operator one time how many hours it had on it? He said the hour meter broke turning over to 15,000 hours. In the early 50s, that was totally mindboggling to me!!! I thought he might be "yanking my chain" as we often said back in Kansas.

After he parked for the day, I went back and peaked at the hour meter---yup it was hung up turning over 15000. Having that many hours in the early 50s, it may have been an early 40s model.

The tractor not going anywhere, might this tractor be a suitable long-term "hobby" for you to tinker with? Hobbies often tend to take money out of the equation. I don't see this D7 as offering any return on investment. Could be a lot of satisfaction if you are so inclined.
 
Cool story ! The older one of the 2 I own, a '44 model has 9999 hours or more, I'd have to look, and it has a different hour meter than the '45 does, which is glass covered and working. One of the neat stories about the '44 is that when we were literally snowed in from a massive storm, the town called upon my father to break a path on the state road, he plowed a couple of miles and the old rock cut about 1/4 mile west was filled in with snow pretty good. He punched through it, all the way to the city line, we were mostly rural around here then minus some houses built in the 30's. This was early 70's, 70 or 71. Nothing could get through, town or state had nothing available, or it was stuck already. I found the receipt, was 3 hours worth at $20/hour back then.

I just enjoy the sound of the naturally aspirated 4 cylinder D8800 engine under a load, straight pipe. They are not super powerful, I have spent time on modern D8's but they sure can still do a lot of work, and surely can push snow, I have cleared 36" or better with mine one winter, like it's not even there !
 
I wouldn?t mind seeing a few pics. The shipping to state college pa would probably cost more than double the cost of the tractor. Do you think?
 
I am going to experiment with posting a video of my brother's 75? year old D7 17A. The video was made about 2001. I think he bought the D7 around 1970.

I did not have my tripod for the camera to record the three of us pull-starting the D7 backwards with a couple of medium size farm tractors--a three man job of course. The D7 sets for years at a time and the gas starting motor is hard to maintain.

I may write more history if the video posts.
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It posted, pretty decent shape. Engine sounds good, not sure if I heard a miss in there or not at lower throttle, minor thing. Funny how those have a turbo, sure sounds very similar to the D8800 non turbo engine. 17A's, oil bath clutch, direct drive, hard to beat that reliable design. Listening to him about the landfill tractor, yes, that is a bad thing, get some wire or similar wrapped up into the final drive bellows type seals, you'll need to remove the sprockets to fix that. They can go bad and leak just from sitting and with that, what leaks out, can also let water/dirt in, which you do not want in that compartment. The radiator bit, sounds like an amateur, too bad, as breaking the track and finding someone with the tooling to pull and put the sprocket back on is not the end of the world for an otherwise good tractor.

I saw the track was stiff and the pins/bushings were not turning, when over the carrier rollers. From sitting I would bet, mine will be the same way. I have heard running in a creek bed or similar, in water will get them free, otherwise need to take the tracks to a shop to have them pushed in/out, turned if need be. Mine are like new, don't need turning, but I know they will be stiff, not sure what I'll do about that. I'll bet the bellows seals will leak on mine too.

With these, you have to run them periodically to avoid all this, the starting engine fuel tanks rust inside, need to keep them full, and the ignition system eventually need work if not used often enough. Good idea to run once a month. I have heard that will also keep the bellows seals from leaking for some reason. The cable control unit on that 17A looked like it worked perfectly, cool old tractor, thanks for posting that !
 

I see my D7 post attempt was successful. Illinois is on virus lock down----my church is closed so I guess for me this Sunday is story-time about my brother?s D7. LOL

ORIGINAL USE OF MY BROTHER'S D7: As near as we can tell, the first owner operated a garbage dump in southern Oklahoma. There are wear-scars on the front of the blade indicating that it has done some push-loading. At Cat, we had a rule of thumb that if dirt needed to be moved more than 500 ft. on a large scale, it was generally less expensive to haul the dirt---using push-load scrapers or trucks and loaders.

I think it is generally known that garbage dumps need to move some amount of dirt in the process of handling and covering the fresh garbage. I suspect that some garbage dumps may need to get dirt that is some distance away. At Cat, we found garbage processing was a good market for MEDIUM size crawler tractors. We considered this application to be generally easy on grouser shoe wear and on the tractor in general. Stink and goo only bothers us humans!!! LOL I speculate that maybe Carl?s D7 grouser shoes are original.

A D7 is a bit LARGE for spreading and compacting garbage. For serious push-loading large scrapers at most construction sites, a D7 would be considered too SMALL. This is a job for the D9-D10 size. Dual D9s are often used to push-load. The D7 might be used with small scrapers. It is difficult to speculate what all the D7 did at the garbage dump.

TO REPAIR THE SEAL OR NOT REPAIR: My brother Carl said the value of the tractor when he bought it, IF THE SEAL WAS NOT LEAKING, the going rate was around $20,000. He paid $9500 for it. To have the Cat dealer with proper tools fix it, the D7 would have ceased to be a ?good deal? for what Carl intended to use the tractor for. What Carl needed was ?a handy brute dozer to use around the farm once in a while?. As it turned out, he thinks he used it maybe 200 hours in 40 years. (In an earlier post I stated he bought it in 1970. Carl bought it in 1980?40 years ago.)

That averages 5 hours a year!!! Carl estimated the leak was about ? gallon every 5 hours. In his situation, the leak was not much of a nuisance or expense. I speculate that the leak would flush out maybe 90% of any farm dirt attempting to enter. We could debate about rain protection. Carl could mostly avoid running in deep water or mud.



Carl's machinery value is not considered to be part of his ?retirement nest egg?---- partly because our dad was a blacksmith and a financially poor farmer during the 30s Great Depression. Dad farmed with fixed-up junk.



All three of us brothers learned the economic value of fixing up ?junk? to farm with. When my older brother died, a junk man cleaned up his farm stuff with few exceptions. For much of Carl?s stuff, the junk man will also be the next owner. A neighbor wants the D7. My hobby farm situation is not much different. My wife asks me what should she should do about my farm stuff if I die before she does? My answer is ?call the junk man?. LOL


IS CARL?S D7 ENGINE MISSING SOMETIME?: Two diesel engine idle noises are generally (1)diesel knock thru the engine walls and (2) exhaust noise. I think the D7 diesel engine knock is uniform indication no miss. Many idling engines have ?exhaust slobber?--- to use an old Kansas expression. This often means a cylinder may have a random weaker fire or a random stronger fire that the other cylinders. As we know, the 40s Cat diesels used pre-combustion chambers.



These chambers were crude, durable, reliable , and not fussy. Especially at idle and if not up to temperature, a pre-combustion chamber?s internal surfaces might harbor some fuel from the violent explosion of ?big drops? of fuel. This might cause more fuel being burned the next power stroke. This ?uneven burn? could create a small amount of unevenness in the exhaust sound.


We have all experienced that many diesels tend to run rough for a few seconds after start-up. This is mostly due more because of an uneven fuel burn between cylinders and due less because of an uneven amount of fuel injected between cylinders.


Thanks for all the feedback.
 
17A's came out in the 50's. First ones did not have a Turbo. I don't know when the turbo was added. They were sold up to 64, but 62 was the last year of any volume. D7E's came out then. I operated a late 17A some, but not a lot. They were a good machine in their day.
DWF
 
DWF, Thanks for the information about the production dates of the 17A. The video indicated that Carl was guessing about the model year. This D7 is definitely not turbocharged.

Questions I have include----- when were hydraulics first used to control the blade on the D7? -----Was the tilt function added the same year? -----Was the cable lift an option for a while?

Additional comments about the leaking seal at the left rear sprocket shaft. It was pointed out in an earlier post that the seal will leak when sitting still. Carl agrees with that. He said it only leaks down a little and then soon stops leaking when setting. Therefore, he always runs the final drive slightly low.

It is generally known that the big gear dips deep into the oil and the oil "goes everywhere" inside the housing causing a bad seal to leak the oil. My guess is that up to 80% of the oil could be lost before the dipping action would stop.
 
What you see on the outside of that tractor is the easy fixes,more than likely water has got into all components,bearings in the transmission and back end are likely to be rusted and will need a total tear down, steering clutches too,everything from the front grille to the drawbar,its a money pit,buy yourself a tractor that's running so you will know what you are getting.
AJ
 
A quick check for water in all the engine and gear boxes is to loosen the drain plugs and see how much water comes out
 
And even at that, I would think that even with condensation, if one was to drain, then flush per the serviceman's reference book, with diesel and kerosene, say finals, bevel gear compartment etc. I'm wondering what issues could be a problem, many of these have sat idle for many years and have been made operational. Reason I am inquiring is, I've got one that I will make operational this year, lot of work ahead of me to do so.
 
Regarding water in the oil compartments. Cat tractors were expected to not be damaged much if caught in deep flood waters. This means oil compartments had to be sealed up good for many years of use and have vents that would not let water in.

Fire may have damages any rubber related to these vents.

Generally speaking, steel needs to be exposed to both water AND AIR for rust to form on the steel surfaces. When water gets into an oil compartment with the oil already in the compartment, the water quickly sinks to the bottom. Steel surfaces under the oil, but in the water, are protected from air and typically little rust damage is caused on these submerged steel surfaces.

I you find oil high on the dip sticks, you probably have some water under the oil.
 

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