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Rod McInnis
 
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Default B-W Velvet Drive clunking


"Charles T. Low" wrote in message
. ..

When put into gear, there is a slight pause, a fraction of a second only,
but easily visible that the prop tranny/shaft does not start turning
immediately - then it catches and away it goes. (Idling just above 600 rpm
indicated.) It does so with a very soft audible clunk, and I seem to
remember it being noiseless when "new" (to me).



Sounds like normal operation to me!

The transmission operates on hydraulic pressure. When you put it "in gear",
you are moving a valve that routes the output of the oil pump (operated off
the input shaft) so that the clutch plates get "squeezed". As with any
clutch, it is designed to engage smoothly, so that the clutch plates slip
just a bit before grabbing hold. When the clutch plates are new the motion
required by the diaphragm would be much less then when it has worn some.
Add in an oil pump that may have lost a little bit of idle speed pressure
and it might take slightly longer for the clutch to operate.

I wouldn't worry about the delay or the clunk. If you are concerned about
the transmission, pay attention to how it works under heavy load
(acceleration). If you ever detect any amount of slip, schedule a rebuild
ASAP.

Rod