D2 cat

[takpak]

For those who might have an older Caterpillar D2 (late 40's early 50's) a question was brought up at a get-together the other day, and I
thought I'd see if anyone here might have an answer! Question was, if you have an electric start pony motor, is there any reason the pinion
from the pony couldn't be engaged to the drive BEFORE starting the pony and engaging the clutch? The person asking was having trouble
getting his pinion engaged after the pony was started, because it was dragging/clashing a bit. Only reason I could think of was you'd be
turning the main engine over while trying to start the pony, but with electric start, fuel off and compression release on would that be a
problem?

Just a "general question" of 'what if'......?

Thanks.

 

[Billy NY]

It defeats the original design, he needs to fix the mechanical problem 1st, sounds like the clutch is out of adjustment or needs replacement. It would make more sense to then go with a direct electric start which would be sized to handle the load of spinning the diesel engine, minus the starting engine. I would have to think that the same size of batteries, cables, electric starter motor or larger would be required to spin both.

One thing is for sure, a properly tuned starting engine in good mechanical condition provides excellent benefits, might be a little extra maintenance work, but is highly effective in cold weather starting by warming the coolant and combustion chamber + moving the crankcase oil as long as necessary before providing fuel and compression. Personally, I hate starting fluid given the performance of a starting engine arrangement, at least on this era of their tractors.

 

[dpendzic]

On my D2 I quite often engage the pinion, but have the clutch released, and start the pony. I do this for the same reason of grinding the pinion gear. The brake on the pinion clutch doesn't seem to work so well.

 

[caterpillar guy]

The problem is the extra power it takes to turn it while starting the engine. He needs to fix the mechanism. Grinding will require the fixing sooner if he keeps up with that. Our D-4 has a bit of that if you just pull the lever then expect to immediately engage the drive. I have to wait a minute for the gears to stop.

 

[dpendzic]

If you take the pinion clutch lever and push it toward the rear of the machine it puts a breaking action on the pinion gear.
Many guys, me included, have changed out the pinion clutch oil to ATF, it has less of a drag on the clutch discs
I usually start my pony without the pinion engaged. once warmed up i shut it down,engage pinion, and start it again with clutch disengaged so the diesel is not turning

 

[takpak]

Thanks all, for your input. It has helped. Issue is, I'm trying to help a friend who's father owns the D-2. Beautiful little "kitty" and he's owned it for most of his life. He thinks it's around a 1945 vintage. He's now 94 and can't get on the Cat anymore, so the son is trying to get it going and operable for the day when it needs to find a new home. It's been stored inside a shop for most of it's time and is a clean little unit. It just sits most of the time now, which is the big problem. I used to work on diesels, but that was in the Navy, and over 50 years ago!!!

Keep the ideas coming, every little bit helps.

 

[dpendzic]

if you can get me the serial number I can get you the year

 

[Bret4207]

If you go to You Tube and look up "Caterpillar D2" you will find a huge series of videos by a guy that goes by "Squatch253" or something like that. He can probably answer your question and likely has a video showing the why and how of the parts working. Very good videos.

 

[Tramway Guy]

If you engage the pinion, but leave the starting clutch disengaged, it should work, as long as your electric starter has enough oomph to overcome clutch drag.

 

[dpendzic]

yes--he came up with a method to slightly dish one half of the clutch plates to eliminate a lot of the drag

 

[takpak]

All is now well, after trials and tribulations. Started out the other day to see if one could get the old Cat running. First, the battery for the starter on the pony was dead, and shot. Wouldn't take a charge. Wrapped rope around original "starter" and no start. Found points corroded. Cleaned points, now it starts, but then stops. Found no gas to carb. Tore apart everything, finally finding inlet to fuel line plugged. Tank was clean though. Cleared that, now had good gas flow to carb. Everything was a bit sticky from sitting so long, but finally got the fuel system working good. Started pony and let it run a while. Finally engaged pinion. It was sticky and sluggish, but with some pressure on the "brake" finally got the pinion to stop and engage without grinding. Engaged clutch, let diesel crank for a while to get warmed up/fluids flowing, then the magic moment, engaging the fuel. Whoo hoo, the old girl fired right up and purred like a kitten. Ran it out of the shop and tried all the clutches and brakes, all worked well. Shut it down for a bit, then tried restarting. Worked fine. Warm oil now, the pinion brake and clutch worked much easier. Going to do some cleaning and fluid changes, but all is well and life is good! The Cat lives again!!! Found the book and specs for it. Picure was taken before clearing the "stuff" out of the way to move it. It is a 1945 D2-J5 model.

 

[dpendzic]

thats great news!! good to hear everything worked ok after sitting a bit--D2's are known for the steering clutches to rust up and stick. The only thing I noticed in your starting procedure was no mention of the decompression lever??

 

[takpak]

Whoops, my bad. Yes, the decompression lever was in use. Upon getting the pony started and pinion engaged, the decompression was activated at that time. When things got to turning over, the decompression was placed in "compression mode" and she started the process of warming her old cold bones up! Ran it for a while that way, then hit the fuel and away it went!

 

[dpendzic]

Excellent!! many guys never run the pony long enough to warm up the diesel sufficiently---good going!

 

[Fatamus]

I was wondering if anyone knows if the ring gear on the flywheel on the D2, D4 are able to be turned over because the teeth are ground off about 1/4" the starter gear has some teeth that are ground back also.

 

[Fatamus]

(quoted from post at 19:44:27 01/31/20) Excellent!! many guys never run the pony long enough to warm up the diesel sufficiently---good going!

I run an old TD9 and run it runs on gas about 3 minutes max manly because the gas side eats a gallon in three minutes between the leaking and the engine and it only has a 1 gallon gas tank.

So what would be a goodly amount of time to run a cat pony? I live in Alaska so I know it mainly depends on the ambient temp and the colder it is the longer it needs to run. Lets say @ 30*F should I let the pony run for 10 min? Or would it be best to just keep checking the diesel intake and head for heat from the pony?

 

[caterpillar guy]

Now that you have it running check the bearings on the round shaft that holds the track alignment. If they get bad they will run the tracks off. As the roller frame gets out of alignment with the sprocket. That is why the D-4's were a much better model with that wish bone like arm under the rear end with the rod bearing looking deal there it could be taken apart easily and is easy to grease.

 

[dpendzic]

Yes---definitely check the track frames for parallel alignment---my D2 had 1 1/2 inches difference in the front to back widths---the outer bushings were shot and quite easy to replace, but i also had a cracked and bent frame rail on one side was so bad that the PO had U bolts holding the idler down!

 

[caterpillar guy]

If you are going to try to warm the diesel up from the little gas engine, you need to keep the diesel turning with the drive. Just let the decompression lever dump the pressure till you want to start it. We always just waited till the oil pressure came up before we tried starting the diesel anyway year around. Meant the bearings were not dry under compression.

 

[caterpillar guy]

If you are going to try to warm the diesel up from the little gas engine, you need to keep the diesel turning with the drive. Just let the decompression lever dump the pressure till you want to start it. We always just waited till the oil pressure came up before we tried starting the diesel anyway year around. Meant the bearings were not dry under compression.
The turning the diesel over circulates the water/coolant to prevent hot spots in the gas engine.