D47U Pony Clutcy

My D47U has a pony motor and engaging the pony to the diesel engine is very difficult. It seems the clutch does not completely disengage. When trying to engage the pony motor, the gearing grinds. I can engage by using the clutch to stall the pony to almost zero rpm.

How do I correct this problem?

clark4u9u

That clutch is a multipul disk oil clutch. They can be a bit draggy. The clutch brake works when you pull the clutch lever towards the starting engine. Personally I would try changing the oil in the clutch to a real light weight motor oil, like 5-30 or so. If that doesn’t help, then adjust. Sasquatch has a really good thread about these clutch mechanisms.

Hope this helps

BP.

An automatic transmission fluid works well. ATF is not as slippery as a motor oil so the clutch can be adjusted to a lighter "snap" and the action of the brake is improved. Usually a simple change to ATF makes a marked improvement without adjusting anything.

Even using motor oil, the clutch does not require a very firm snap to spin the diesel engine just fine. The clutch adjustment should be as loose as possible to lessen the drag from oil between the disks. It is not at all like the main clutch between the engine and transmission.

As CCJersey mentions, ATF works great. Rather than tear the pony clutch apart, drain the housing and flush with solvent, diesel or whatever, and then refill with automatic transmission fluid. I’ve done this to several pony clutches and it works great. If that doesn’t cure things, then you may consider re-adjustments to see if it helps. JM