I am trying to bring a D2 3J back to life. The main clutch is stuck in the released position. I have taken off the cover plate and can see the throwout bearing and spider. I got the throwout bearing to move a bit, but the spider only moves a tiny amount. I compared it to another D2  3J and it seems that the disc is supposed to have movement in it. The spline on the inside of the disc is stuck. PB Blaster and prybars have not worked.  Any ideas?  I am trying to avoid pulling the engine.    Thanks.

If the engine runs, put in the plug in the bottom of the clutch housing and put in enough kerosene (if the compartment is dry) to fill slightly above the bottom of the clutch disc, (add  more as needed), or use water if the compartment is damp.
Start and run engine for a while,15-30 min, then with engine running try to operate clutch.
When done, drain and repeat with the same fluid used to rinse.
Water often works very well for this, but if you do use water you must rinse well, dry completely by heating sufficiently and oil any moving parts, linkages bearings etc, when dry.

Is it corroded? I bought a 5T this past Spring from Juiceman, it started off as a parts machine but I decided give it another chance at life after I got the diesel unstuck and running. From the attached pictures you can see how extremely bad it was. The clutch was stuck in such a way that even after unbolting the engine it didn't budge. I couldn't believe that the stuck disc was holding the weight of the engine. I had the engine rigged with my forklift and tried to lift and drop a little way quickly to get it to break loose and even that didn't work so I ended up taking the clutch apart to get it out. After going through that I did the steering clutches on it and it's turned out to be a nice little machine. Believe it or not I cleaned up the pressure plates, installed a new disc and she operates smooth as silk.

CrawlerAddict 

Those pictures show me more than looking thru the little cover plate that I have removed. What I think is stuck is the small gear/spline at the center of the plate. I cant see any movement in this one, but on the other 3j, I can see about 1/4 inch of movement. It is hard to work in that small space and I am trying to avoid removing the engine. I bought this as a parts machine with main and steering clutch levers stuck, but if I can get the main to work I will try to tow start it and see if it is worth getting it going again. Overall it looks in pretty decent shape. If I dont get it free soon, I may try to get the pony running and the big engine and fill the clutch compartment with diesel and let it run for an hour or so. That will tell me if it is worth saving, since if I get that far, I still have to do the steering clutches. I dont look forward to them. Thanks folks, the Saga continues. Grant.

Back at the D2 again today. Decided to see about getting it running to maybe free up the clutch. When I bought it the owner said that it was on the property when he bought the ranch and he had a mechanic try to start the Cat. He said it roared and blew so much smoke that he thought the engine was blown. That was years ago and it sat in the shed until I bought it couple of years ago.

Today, I worked the throttle and it seemed stiff and not enough travel. I went and tried my other 3J and it was free and much more travel. I am working on getting the rack and the governor freed up. It is no wonder that the owner thought it was blown. It must have sounded awful. Onward in Cat Land. Grant.

You guys have all the fun!
Wow, the innards on that D4 are so RUSTED its scary. I want to ask the nice lady again if it went thru a flood. It was parked next to the Sacramento river in a flood zone...
If I sat that long, I would be rusty as well. That's why I opt to keep moving to keep from getting too stiff.
Good luck on the D2 Grant. Just like Crawler Addict, you have a reason to get out of bed each day to breathe some life back into on of your machines.
Keep up the great work! JM

JM well you have the flood of 1955, February 1986 and New Year’s Day 1997.

From experience anything that was down on the other side of the levee would have a fine coating of flour like soil everywhere… and i mean everywhere even in 99.9% welded steel tubing frames.

Even stuff that doesn’t go under the water, just sitting down near the river or in SJ/Sac Delta, the inversion layer starts at the bottom of the valley and there is a different microclimate that leads to condensation that rusts things from the inside out.