conor54
Member
Towards the end of the season I had some problems with the gearbox. The engine is running well but there seemed to be no drive when the revs go up. The propellor is turning but it seems that only a fraction of the usual power is actually being delivered at the prop. Not sure the age of the gearbox but definitely more than 20years!
I did some experiments one evening while it was very calm. Turned the boat around on the mooring so she was moored by the stern and tried going ahead. Not much push. Disconnected the gear cable from the lever on the gearbox and put it into forward - much more drive. So maybe the lever wasn't being thrown far enough. I adjusted the cable position on the throttle/gear selector so it should travel further and on the gearbox level so that for a given travel it should rotate through more angle.(See diagram). This seemed to work. I cast off and motored around the moorings at 5 knots and did some backing up and going forward etc. Not sure if this is a proper long term fix or does it just postpone things. However on the day we craned out I thought again that there seemed to be less than full thrust.
Is this a known type of failure mode for these gearboxes?
I did some experiments one evening while it was very calm. Turned the boat around on the mooring so she was moored by the stern and tried going ahead. Not much push. Disconnected the gear cable from the lever on the gearbox and put it into forward - much more drive. So maybe the lever wasn't being thrown far enough. I adjusted the cable position on the throttle/gear selector so it should travel further and on the gearbox level so that for a given travel it should rotate through more angle.(See diagram). This seemed to work. I cast off and motored around the moorings at 5 knots and did some backing up and going forward etc. Not sure if this is a proper long term fix or does it just postpone things. However on the day we craned out I thought again that there seemed to be less than full thrust.
Is this a known type of failure mode for these gearboxes?