Left side no go! Well sometimes it doesn't.?!?!?!?

[notmeu]

I have read multiple posts about the final drive clutch issues, but I cannot see to find an exact topic regarding a problem I am having with my left final drive not having power, sometimes. If I drive up to a large pile of dirt or tree and with all of the inspection covers removed I can see that the pressure plate is not spinning. If I pull the right brake lever the motor does not stall. The puzzling item is if I am not putting a lot of force on the left side tracks the pressure plate will spin providing power to the left side. Is it possible that the plates in the clutches need replaced? The fingers that touch the throughout bearing are not perfectly aligned. There is probably a 1/16” difference between all of the clutch levers. So some of them hit the bearing sooner than others. I tried adjusting the throughout bearing but never got any good results, I will say there is very little adjustment available though. I was looking for some words of wisdom before I tear into the final drive. I thinking that it is the clutch pads. Any help would be appreciated.

[Lavoy]

Sounds like the clutch is worn out, assuming there no oil contimination, pressure plate springs may be getting weak too. Only fix unfortunately is to remove the final and replace the clutches.
Lavoy

[notmeu]

So you saying oil contamination inside the clutch plates? What is the minumum thickness range for the plates? Fiber and metal. Also the plate springs are pretty tough to move. They'll move with a long screwdriver, but it takes some effort. What determines replacement of the pressure plate? How exact does the pressure plate springs have to be? If they are within a 1/16" is that fine? I also replaced the 4 springs that holds the throwout bearing about a year ago. Unfortunally I didn't take apart the clutch plates since everything was working properly. No atta boy for that one!

[Lavoy]

Minimum thickness is in the service manual, I don't remember of the top of my head, and if I did, probabably wrong. Thickness is irrelevant if any oil is present, throw them away.
To me the criteria for replacing the pressure plate is if the final drive is off. Same as clutch discs. I have had enough redos from reusing used steering clutch parts, I quit doing it years ago.
Lavoy

[gregjo1948]

I had good luck cleaning oil soaked clutch discs. I soaked them in gas over night then wire brushed.(on bench grinder) Then I used a torch to burn the gas and oil out. The oil/gas combination bubbled and burned leaving the disc clean and dry. I lit it and blew it out many times so as not to damage the disc. When it stop bubbling and coming to the surface I was done. It did take some time to do all of them, but they were all in good shape and at $18-$20 apiece, it was well worth the effort. Greg

[Lavoy]

Bear in mind that on the whole, gas is no better than the oil. Amy sort of petroleum comtamination on a fiber clutch surface of any sort is bad. Obviously people can do what they want, but is it really worth having to redo the whole job just to save $140-$160?
Lavoy

[gregjo1948]

I did this disc cleaning about 4 1/2 years ago and have put nearly 250 hours on the machine since. The clutch is working just find and I'm still happily saving $140-$160. Don't knock it unless you've tried it. It worked for me. Greg

[Lavoy]

I have tried it, and in my experience, it did not work. If it worked for you, that's good, it just has not worked for me.
Lavoy

[Labrador_tractor]

my buddy put his 350B disk's on his BBQ to burn off the oil, worked fine for him but his disk's were the metallic ones, not sure how our fiber disk's will hold up to the the BBQ.

[woodsman]

If you can get your hands on Toluene, the problem solved. One of the worlds best solvents for removing oil and grease from anything. It's used quite extensively in the industrial machine cleaning business. Just be careful, as it will eat up most types of chemical gloves.
Martin

[cdunn]

I think I would be more interested in finding how the oil got on the clutch plates to begin with. That problem has to be fixed first. My opinion, I'm sure not going thru all that work of pulling finals and then put used clutch plates back in and thats based on past experience.

[woodsman]

Oh, you're certainly right there. Just saying, if the disc's were fairly new and got oil on them, I don't know any better material to use to clean them. Chances are finals got to be torn down anyway to find where its coming from. I cleaned mine years ago using Toluene and have never had an issue since.
Martin

[notmeu]

Well the oil/grease got into that part of the final drive because the previous owner had a bad seal that was around the bull gear so what he did to fix it was pump grease into the bottom cover of the final drive and then he put the cover back on. Talk about a mess. I very lightly used the 420 for a week when I purchased it and then I tore everything down and replaced all of the bearings and seals in the finals, but since I'm a first timer and the clutch discs seem to be just fine I never touched them. Although just about everything else on the 420 was replaced, I'm kicking myself for not doing it now. O'well another weekend project!

[Lavoy]

Look at the bright side, you will have lots of experience when you buy another crawler.
Lavoy

[notmeu]

I agree with you on that one! I hate doing it the hard way! Although I did buy a parts crawler last night! The parts are not for the clutches, just to put on the shelf.