Clutch problem?

[Meck]

Hello all,

I seem to be having an upper cone clutch problem with the SD40 Yanmar saildrive, but I am not entirely sure.. The symptoms are the drive engages and works fine when cold, but after warm up the propulsion decreases, but only in reverse. The gear oil looks fine, no metal dust, no clouding, no burnt or smelly residue.

I went through the process of changing oil to a high quality synthetic with an oil stabalizer, then shifted the transmition a number of times from forward to reverse and again the transmission always engages. But after getting slightly warm propulsion again decresses in reverse.

If anyone is familiar with these drive symptoms, please let me know.

And, if anyone has changed out this upper cone clutch on the SD40 I would really appreciate a heads up on the procedure. I do have a service manual and parts catalog on order.

Cheers,
Meck