Cat d4 basket case

[yrens]

Hello all, I recently posted in search for a few needed parts for a 49 D4 mainly the main clutch lever which I now have. Its been sitting approx 12 years. So my issue is, the main motor is locked up. Can't turn it by spinning the radiator fan at all. The main clutch won't engage and is currently stuck in neutral. It appears to move just a touch when I move the lever back and fourth but just wont move. I did pour some oil in all the cylinders through the injectors. The lower crankshaft compartment looks great when I removed the side inspection panel. I disconnected the interlock rod to see if that would make a difference and it didn't.
Any thoughts and feedback will be greatly appreciated. My thoughts were if I could engage the clutch could I then engage the starter motor clutch and put a 2 1/4 wrench on the pony motor flywheel pulley and see if it could move the main engine to free it up.

Jeff

 

[Lumberjack Matt]

Reminds me a lot of me in this thread from last year :
https://www.heavyequipmentforums.com/threads/should-i-take-on-this-project-50s-cat-d4.89180/
In my case, the engine was locked because the gears in the timing cover were rusted over, but it still spun about 30 degrees. Is the compression lever open? Does the pony motor spin?

 

[yrens]

How ironic, I saw your thread and saw your pictures not knowing your other identity. I have seen many of your posted videos. Thanks much by the way. Your first encounter is much like mine. In the weeds for 12 years. It was my uncles who recently passed away. When I went to visit their farm which they have leased land since 1978 I saw this Dozer and it intrigued me. Since i'm a Airline Technician I was up for the challenge to work on something I knew nothing about. Anyway, yes I have the pony motor running, compression lever open. Top of the engine looks great under the valve covers and so does the crankcase with inspection cover removed. There were parts stolen from it, one being the air cleaner assy. Which I believe how the motor got locked up. I have no real good access to the front cranks shaft. So will it work through the pony motor with starting clutch engaged which that wont do? I currently have acetone and brake fluid sitting in each cylinder as of 9/15. I have approx under two hour drive to the place where it is at rest. So any thoughts since you have become the pro?
Thanks very much for responding by the way.
Jeff

 

[Lumberjack Matt]

I don't know much about the pony pinion clutch cause mine didn't have one. If the main clutch is stuck in the disengaged state though, I don't think that affects the pony engagement. The pony uses the outside gear on the flywheel, and the main clutch uses the inside gear.

Did you check to see if the valves were free? You should be able to move them all, but if the intake or exhaust was left open they might have frozen. If you can't get them to move you can tap on them with a deadblow after soaking them with penetrating oil to free them.

If I recall, I remember trying to bar the engine over by taking off the clutch inspection cover and putting a pry bar in there to spin the flywheel. Might be worth a try if you can get the angle right. How much access do you have to the front of the engine?

There might be a few other things to check depending on how it's configured.

 

[yrens]

Are you referring to the big square panel between your feet? I see the clutch there but I don’t know if there is another inspection panel to see the engine flywheel that would be in front, if that is what your referring too? I see inner and outer teeth that are meshed together. I can’t put a pry bar on the teeth for that reason.
I’ll check the valve movement on my next trip. Access is very difficult on the front of this D4 due the unique nose it has. Never seen one like it. I wonder if I could get a local farmer to tow it out a bit and see if it could beak something loose. It’s lower tracks are becoming part of the earth

 

[Lumberjack Matt]

Yes that cover, if you can't reach the flywheel from there, there is a timing inspection cover on the right side of the bellhousing where you can reach the flywheel, provided you can get around the oil filter housing...there is also a drain plug on the bottom of the bellhousing where you can bar it over from. Hopefully you can reach one of those.

Send me an email if you want the service/parts manual, I have electronic copies of them.

 

[yrens]

I did try that a bit but I will look for that other inspection panel that I know where your talking about. I think there is so much grime that I haven't seen it. What about that cover for the generator? Could you pry on that gear? ? Just thought of that a bit ago.Sweet on the manuals, I do have the service and ops but really could use the parts one. [email protected] is my email. That be great if you could do that. I was going to actually ask you if you had the p/n for that cover #12 for the shift assy. On page 47 of the service man. I brought it home to clean up and it looked like something out of the Titanic. I have the boot thanks to you already I plan on heading back to the beast in a few days.
So where you at with yours? Last I saw starting to paint. How is that cool dog of yours. Thanks again Matt.

 

[Lumberjack Matt]

The gear teeth in the timing cover are way too small to be prying on. You could pull that cover off though and see how rusty it is in there. It might be worth it to get one of those cheap borescopes off Amazon to look in there and in the cylinders. Most likely the cylinders have seized up due to the intake being open, but you probably already knew that. I would be careful about prying too hard on the flywheel teeth, it might take a lot of force to get a cylinder unstuck and you definitely don't want to be snapping any teeth off.

Like you said, the best idea might be to focus on getting the clutch working so you can have someone else tow you. Get up to speed and then drop the clutch and hopefully the engine breaks free.

I am getting read to reinstall my clutch and engine, then I can finally fire her up.

 

[skyking1]

when the engine " breaks free" that can often mean broken rings. There is no walking that one back. I suggest keep adding oil to the cylinders and gently barring it over, rather than applying towing force to it.

 

[yrens]

The gear teeth in the timing cover are way too small to be prying on. You could pull that cover off though and see how rusty it is in there. It might be worth it to get one of those cheap borescopes off Amazon to look in there and in the cylinders. Most likely the cylinders have seized up due to the intake being open, but you probably already knew that. I would be careful about prying too hard on the flywheel teeth, it might take a lot of force to get a cylinder unstuck and you definitely don't want to be snapping any teeth off.

Like you said, the best idea might be to focus on getting the clutch working so you can have someone else tow you. Get up to speed and then drop the clutch and hopefully the engine breaks free.

I am getting read to reinstall my clutch and engine, then I can finally fire her up.
View attachment 268298

Looks awesome I’m excited for you believe me!
I knew there had to be a reason I haven’t heard anyone suggesting that. Makes sense. I was able to see down the injection holes ever so slightly and looks like some surface rust at the minimum on some of those cylinders. Hopefully the oil will do some help. I’ll maybe inspect with the cover off and see if I find anything else. I’ll keep in touch. Thanks much for the advice.

 

[yrens]

when the engine " breaks free" that can often mean broken rings. There is no walking that one back. I suggest keep adding oil to the cylinders and gently barring it over, rather than applying towing force to it.

You have good point there is the risk. I’ll keep going with other means. It’s in neutral at the moment stuck I wouldn’t mind having it pushed out of the spot it’s in just to give the whole track a good look and a better spot to work.

 

[skyking1]

My partner broke rings on one of the airplane engines by being impatient, so I am a little sensitive to that issue.

 

[TomA]

I think using a wrench on the pony to try to turn the engine is the best plan. I think you could work it both ways if you can get it to move. You will have the most mechanical advantage with that method.

The pony clutch is an over center clutch. Try the adjustment under the plate with 2
bolts. You want the clutch to snap over center.

 

[yrens]

My partner broke rings on one of the airplane engines by being impatient, so I am a little sensitive to that issue.

Ahh, I understand

 

[yrens]

I agree, I will be heading to it in a day or two. I was thinking of trying to adjust and see if I can get it to move. I’ll post my results. Thanks.

 

[D5Dan]

Certainly not a make or break, but if you do push/pull it out of its hole…I’d recommend rolling it up onto two (or three) 2x10’s per side, that will get you a bit more space under the machine to inspect/check (or keep it from freeze in, depending on where you are). Also helped my under-machine-access when I got my blade halfway up and supported… I spotted a number of “how the hell did that get up in there’s”! Cool old machine! Good luck…post up some pics so we can see the “fun”!!

 

[yrens]

I hear you. I was at it today and had no luck yet breaking it loose. I was trying at the timing inspection cover Matt mentioned. I spoke to the neighboring farmer to see if he had anything to pull it out a few feet. He said he give it a try. So hopefully I can get it into a better spot to continue on. Maybe later this week. So currently I’m stuck in neutral, clutch won’t engage and a locked up motor
I get a bit deflated every time I leave it without it broken free. But I’m determined.

 

[yrens]

I think using a wrench on the pony to try to turn the engine is the best plan. I think you could work it both ways if you can get it to move. You will have the most mechanical advantage with that method.

The pony clutch is an over center clutch. Try the adjustment under the plate with 2
bolts. You want the clutch to snap over center.

Hey Tom I’m a bit puzzled yet with the pony clutch. Currently it’s not anywhere near the brake. What has to happen to get it extended? Nothing I do with the lever makes a difference as it currently sits. I hear light clunk but I don’t see any movement.

 

[yrens]

Yes that cover, if you can't reach the flywheel from there, there is a timing inspection cover on the right side of the bellhousing where you can reach the flywheel, provided you can get around the oil filter housing...there is also a drain plug on the bottom of the bellhousing where you can bar it over from. Hopefully you can reach one of those.

Send me an email if you want the service/parts manual, I have electronic copies of them.

Well Matt I did try the front small inspection cover like you suggested. I removed the oil fill and breather to help with access. No luck yet. I’ll keep trying. I have a very dumb question, where do you fill the transmission? I have a breather and a fill stick and those holes are way too small. My service manual never shows where?
Jeff

 

[TomA]

You probably need to tighten the pony clutch.