The original Hurth transmission on my M25 is apparently at the end of its life after 1800 hours. I put about 50 more hours on it on the Hawaii cruise, not including running in neutral 40 minutes a day to recharge 15 or so amp hours.
The symptom is a squealing noise occasionally in gear above 1500 rpms, which is relieved by reducing throttle and resetting to 1400 rpms. The throw of the trans lever is good and and the fluid has been maintained correctly during my ownership. I always sail with reverse gear engaged.
What is the cause of the squealing noise? Why is it unpredictable? Is there any ambiguity in the diagnosis of new-tranny-needed? I ask because of a Frank Langer experience posted two years ago:
I had the same sound with our Hurth transmission, the grinding sound coming without warning. I would immediately shift to neutral, then back into gear and it would be fine until it happened again, sometimes within 5 minutes sometimes an hour later--very unnerving. The fluid level was correct and looked fine, but it still happened.
I replaced the Hurth with a Twin Disc transmission and it has been working well, though the same sound has occurred on two separate occasions, both when motoring in rough seas.
The symptom is a squealing noise occasionally in gear above 1500 rpms, which is relieved by reducing throttle and resetting to 1400 rpms. The throw of the trans lever is good and and the fluid has been maintained correctly during my ownership. I always sail with reverse gear engaged.
What is the cause of the squealing noise? Why is it unpredictable? Is there any ambiguity in the diagnosis of new-tranny-needed? I ask because of a Frank Langer experience posted two years ago:
I had the same sound with our Hurth transmission, the grinding sound coming without warning. I would immediately shift to neutral, then back into gear and it would be fine until it happened again, sometimes within 5 minutes sometimes an hour later--very unnerving. The fluid level was correct and looked fine, but it still happened.
I replaced the Hurth with a Twin Disc transmission and it has been working well, though the same sound has occurred on two separate occasions, both when motoring in rough seas.
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