davidspark
New Member
Hi all,
I have this transmission attached to a TMD41D, both from 1994 with about 2,500 hours. It's lost reverse.
I was manoeuvring in a marina when the engine stalled at low revs with an unpleasant mechanical noise for about a second or so. Upon restarting it happened once more, but then seemed OK. I thought perhaps something had been wrapped around the prop which had cleared, and checked the shaft was turning properly in both F and R gears - I must have shifted back and forth 15 times without any problems. Next day, all was fine but after motoring for about 4 hours I found that R didn't engage at all - the engine revs freely as if in N, and there is no unusual noise / vibration / etc from the transmission. It seems to work fine in F, and the shaft turns freely by hand in both directions when in N.
I have confirmed that it is not the linkage by taking the cable off and manually actuating the shift lever. I took the hydraulic valve out and inspected for blockages etc, but all looked fine and it was turning in the housing properly. The oil filter looked quite dirty with black residue inside, however.
My working theory is that a disc in the R clutch became damaged / warped (thus the initial stall / noise), and that running the engine in F for several hours with a damaged R clutch disc caused sufficient further wear / damage that it no longer engages. That would seem to be consistent with the dirty oil and the failure only after several hours' motoring the next day. But if others have alternative theories I'm all ears.
Although the transmission is getting on, parts are still available from VP - including the clutch packs and seals / gaskets etc. I've been asking around for somebody in the Solent area to rebuild the transmission but am getting the impression this is a fairly niche area. If anybody can recommend someone who might be able to help I'd be grateful.
Thanks!
I have this transmission attached to a TMD41D, both from 1994 with about 2,500 hours. It's lost reverse.
I was manoeuvring in a marina when the engine stalled at low revs with an unpleasant mechanical noise for about a second or so. Upon restarting it happened once more, but then seemed OK. I thought perhaps something had been wrapped around the prop which had cleared, and checked the shaft was turning properly in both F and R gears - I must have shifted back and forth 15 times without any problems. Next day, all was fine but after motoring for about 4 hours I found that R didn't engage at all - the engine revs freely as if in N, and there is no unusual noise / vibration / etc from the transmission. It seems to work fine in F, and the shaft turns freely by hand in both directions when in N.
I have confirmed that it is not the linkage by taking the cable off and manually actuating the shift lever. I took the hydraulic valve out and inspected for blockages etc, but all looked fine and it was turning in the housing properly. The oil filter looked quite dirty with black residue inside, however.
My working theory is that a disc in the R clutch became damaged / warped (thus the initial stall / noise), and that running the engine in F for several hours with a damaged R clutch disc caused sufficient further wear / damage that it no longer engages. That would seem to be consistent with the dirty oil and the failure only after several hours' motoring the next day. But if others have alternative theories I'm all ears.
Although the transmission is getting on, parts are still available from VP - including the clutch packs and seals / gaskets etc. I've been asking around for somebody in the Solent area to rebuild the transmission but am getting the impression this is a fairly niche area. If anybody can recommend someone who might be able to help I'd be grateful.
Thanks!
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