On our good old D6C we are having a problem with the decelerator where when it is depressed, it pulls the throttle lever to idle & we would like to get it working correctly again. I remember running a D8K many years ago that had the same problem & there was sort of a round race with balls & springs in it if I remember correctly that the mechanic did some work on got it working good again. We had a look & are not sure if there is something to service here or not. I see in the parts breakdown to the left of the long cylinder thing there is a mechanism showing two rollers & two springs. Is there somehow something there that can be serviced to restore proper function? Any advise would be appreciated.
I suspect the two bell-cranks on the pivot in view A-A where the throttle and decelerator connect are sticking. Try taking that pivot apart and clean it of dirt and rust.
Here's some generic instructions... Basically take it apart, clean it up, light oil only, look for any flat spots....
Thanks very much for the replies...…...much appreciated!
Our mechanic got the decal assembly apart & cleaned up the inside. Didn't find a lot wrong other than it needed a good cleaning inside, with things being kind of rusty he said. Nothing seems wore too bad except the assembly moves some in the housing, up & down almost 1/16". He is going to put it back together & see how it works & order some bushing parts if it is still not working right.
Metalman, your trick here is to use a Cable tie (Zip Tie) to hold the rollers in place as you assemble this item, oh and the lube thing is not to be used as it will NOT work correctly, a fine dab of grease on the spindle is O.K. but put nothing on the rollers or hub.
Good to see you back TC please stay
I rebuilt the decelerator on my D6 a while back. The trick to getting mine to work right was to clean up the flat surfaces that the rollers ride on. I cleaned it up on my surface grinder and that gave it a nice flat surface. There was just a little spot worn where the rollers ride, hardly noticeable, but is enough to keep the rollers from working like they should. The shaft bushings were also completely shot so I replaced them. The decel is kind of a poor design in that it catches and holds dirt around the shaft and rusts and wears parts out. I also added a grease zerk on the outer bushing so I can keep it lubed. The best thing I did was to replace the heavy return spring that's in the linkage. After a day of running the dozer my ankle would be sore from pushing the decelerator pedal. The spring is held in a tube in the linkage and is crimped in. I just carefully uncrimped the tube and replaced the spring with one that's not so stiff an re-crimped it......MUCH better! Good luck
Any marks inside the roller cover (Hub) can easily be sorted by rotating the cover to a new position, any grease on the rollers or the path they go against will make the item useless, the rollers need to grip the roller path, the unit is sealed mainly with a paper gasket that is important to be used as it gives clearance to the moving parts.
YAY !!! Tony is back !!! Awesome.