4 replies to this topic

[foreverfixin]

I’ve just been cleaning up my primary gear and have noticed a couple of things.

 

a) there are holes around the circumference drilled through the body just by the helical gear teeth. They emerge in the bore by the edge of the plain bush. Presumably these are for oil to lubricate the bushes. What’s puzzling me is why oil doesn’t or can’t escape at the crankshaft tail at the primary gear retaining ring/C-clip and get into the ‘dry’ clutch area.

 

b) covering the aforesaid holes is a continuous coiled spring ring which I’ve never noticed before (why it hasn’t fallen off and got lost with all the handling it’s had beats me). I’ve never read about this part and wondered what is its purpose?

[Earwax]

Is b)  the inner spring of primary seal oil cover?

[nicklouse]

Is b)  the inner spring of primary seal oil cover?

Sounds like it.

[Spider]

The holes are vents to let any oil out. With it wizzing around at crankshaft speeds, no oil is going to enter via those holes. It is in part, also these that help stop oil getting out the via the back bush (the top hat one). It is important that the holes are clean and clear or you could end up with Oil on the outer face of the Flywheel, it shouldn't end up on the plate though. The front bush is designed to run with minimal oil ('just a smear' according to the factory) and the original Deva back bush is designed to run dry.

 

The spring will almost certainly be from the Seal as Earwax has suggested.

[foreverfixin]

I knew there would be an explanation for the oil holes. And, yes, the spring ring is indeed out of the primary gear oil seal. Thanks to you all for your help.