Wow !!! the General Gear site is amazing. I went ahead and ordered the clutch compression release tool. The youtube videos by Pacific Northwest Hillbilly look to be a wealth of information. I tried to subscribe but being a techno dinosaur it didnt go well. I dont have time right now, but I can see hours of viewing of his videos in my near future. From General Gear I learned that the RD4 parts and my 6U steering clutch parts should be the same. Later in the U series they made some changes, but my 6U is early enough to be the older style clutches. Thanks again, Grant.

John Parks who owns General Gear is a really good guy to deal with too, I bought new steering clutch plates for my D2 5U from him, and new brass radiator tags for D4, all were great quality.
Let the fun begin, you might be a techno dinosaur like me Grant, but I'm sure you can post some photo's of what you find....
Mike

www.alphachemicals.com/citric_acid

ballistol.com/uses/other-uses/

Bursitis,Thank you for the link. I had not seen that citric acid seller before. I will order tomorrow. Does anyone know what percentage that the acid should be mixed to?
Mike and Neil, I will post photos when I make some progress. I also know how good proper steering clutches and brakes feel. I have a D2 crawler that the clutches and brakes are perfect but the pony is shot and it is a 3 cylinder engine (not intended to be) and the tracks are badly worn. I have to choose my battles and the D4 is the most important of my many (too many) Cats that are mostly projects. I have come to the conclusion that I have to live to be 150 years old to finish all of my projects (if I dont start any more) so I prioritize.
After the D4 there is a wheel tractor that needs work on the rear end and then a Cat 22 that I need to pull the engine to convert to electric start (too damned old for this hand cranking stuff) and the a couple of my brothers D2s and his D4, and on and on and on. But it beats sitting in a rocking chair doing nothing. Its all fun. Grant.

Grant, I use a lot of citric acid baths here, it isn't a exact science by any means, sometimes I might mix up a small container of maybe a gallon of water, into that I'd put around maybe a 1/4 of a coffee cup of acid, while for bigger jobs, like rolled up tracks, I have a larger plastic cattle trough / cistern that is about 150 gallons of water, into that I'd use 2 or 3 scooped handfuls of acid, in warm weather 10 days is plenty of time, often no more than 7 is needed.

Remember to dissolve the acid in hot water first, I bought my 50 pound sack from a restaurant supply store, it's just a benign food preservative, I never wear gloves when I'm handling it, I reckon regular salt would burn hands more, but then my hands might be a little tougher than some folks, and I'm not very bright I like to remind folks, so take my advice with a pinch of, well salt...

Your place sounds like mine
Mike

Now that bursitis has shown me a link to buy citric acid I am going to try it first. I have been hesitant because I am working near or at freezing temperatures and I thought the acid bath needed to be warm. I have a couple of old clutch packs that have been laying behind the barn for 40 or 50 years and will start with them just for learning . I can heat 10 gallons of acid bath easily but heating 7 tons of iron outside is not going to work too well. I will try it on the machine since it is unusable as is, and I have nothing to lose if it does not work. It would be great if it works, since I have acres of brush to clear and the D4 will be perfect for that. Grant.

The trick in winter Grant is to move your acid bath inside near a heater, obviously not easy with a whole crawler, but a cross shaft can be stood up in suitable container, I often have a plastic bucket with something small soaking in the house in the cooler months, a mans gotta do what a mans gotta do to get a dead Cat sorted..
Mike

If you can rig it up, it works well to circulate the citric acid. I used a small fountain pump when I did the radiator on the D4. Hot water and warm weather do help a lot.

My 10 lbs of powdered citric acid arrived this week and the clutch pack spring compression tool from general gear arrived also. it is supposed to start raining tonight and keep up for most of the week so I dont expect to get much done until after Christmas. I am sure that I cant heat the whole back of the machine, so I am going to try the acid bath cold. I will put a small fish tank bubbler down to the bottom to do a bit of circulation and a long soak and then drive it back and forth in my limited space and hang onto my lucky rabbits foot while I do it. We will see how that goes. If no luck the top of the tranny comes off and I work from there. Pray for citiric acid. Grant.