my 88 d3c with shuttle shift(3 forward, 1 reverse) is stuck on my trailer. it was left parked for about 6 weeks now will not move. it is an all mechanical machine. I can make the left track engage but that's all. I need help.
See if you can pull forward on the long linkage that attaches to the big "hump" on top of the steering clutch/brake compartment or push the arm on the hump forward. It sounds like the cam type deal inside the hump is stuck. If you take the covers with humps off you can lubricate them and free them up. The repair manual shows how they go together. One of mine was assembled wrong in the past but still operated smoothly so I didn't bother taking it apart. There was enough adjustment in the linkage to get proper free play and brake operation. The only minor issue I noticed is the spring at the back that pulls the cam back is stretched out a little bit at rest where the other side has just slight tension on the spring. You could take the spring off and the linkage arm (it should have a simple to remove hair pin on it) and try to work the cam arm back and forth to free it up. You might be able to spray some penetrating oil on the ends of some shafts. Oh, and make sure all the linkage pivots and brake pedals pivots move freely. Mine was missing the spring for one of the brake pedals but I was able to match it up really close with a generic spring. Cat wanted a ridiculous price for a simple extension spring.
thank you. all linkage seems to move freely. I removed the cover to verify all was still connected and it was. I noticed on the steering pedal two rods, one to the hump ( parking brake) and the other rod goes to a "hydraulic valve" with several hoses going to it. one on each side. what am I looking at? how do I check it? I do not have a tech manual, but obviously I am going to have to get one.
The long rods that attach to the humps are for the brakes. The shorter smaller rods going to the valves, with the hoses, are the steering clutch valves. The valves have rollers on them that can get flat spots and need to be replaced but they wouldn't affect the brakes locking on. If there was an issue with the valves it would cause the machine to be difficult to turn because the steering clutches wouldn't release making the machine keep going straight. I think the engine could possibly load up a bit and a non functioning steering valve(s) could cause the brake brands to wear a lot faster. The brake is trying to slow that side but without the steering clutch working the machine wants to keep going straight.
Post a Serial Number. That will identify the appropriate manual and allow you to search for one on the net.
5kg00498 i serial number
Are you looking for a service manual.?