Westerly Merlin drive coupling (?) failure

[frderek]

Westerly Merlin 28 (1985); Bukh DV20

I went to take the boat out yesterday and found that when fowrward gear was engaged a banging/slapping noise came from below. In reverse there is no problem. I quickly turned back and tied up again. Today I shall get the wellies on and walk out to inspect the propellor but opinion in the yacht-club was that the drive coupling has 'gone'. Any advice on diagnosis and repair would be much appreciated: as would a source of any spare parts I may need. Photos (probably) to follow.

Later: OK so the cause of the banging seems to be a knackered rope-cutter. The question is, has the cutter come out of its V because of a shot drive-coupling?

tia

Derek

(posted to PBO and WOA fora)

 

[Happydaze]

Same noise happened on mine so i dived under and removed the striker plate and all quite now. I have now got a service kit from Ambassador for next time i'm out of the water. For the stationary cutter to come out of the V, the shaft would have to move back at least 10mm so it may have come out last time the shaft was disconnected from the gearbox.

 

[frderek]

Same noise happened on mine so i dived under and removed the striker plate and all quite now. I have now got a service kit from Ambassador for next time i'm out of the water. For the stationary cutter to come out of the V, the shaft would have to move back at least 10mm so it may have come out last time the shaft was disconnected from the gearbox.

Drying moorings have their disadvantages but at least my boat is 'out of the water' twice a day Having identified the cutter as an Ambassador, their web-site proved very useful. I seem to have lost the clamping ring altogether so I need one of those plus the service kit, I think. Have booked the drying pad for Wednesday for pressure-washing (overdue) which will let me see what's going on with the rope-cutter and fix it without being up to my ankles in silt. The (allegedly) stationary cutter is completely loose on the shaft and was causing the banging noise in forward gear.

 

[Happydaze]

I think if you had lost the clamping ring, you would have lost a cutter so looking forward to hear what you find. I didn't look too hard at mine but know the fixed cutter has become very sloppy and hitting the other cutter.

 

[frderek]

I think if you had lost the clamping ring, you would have lost a cutter so looking forward to hear what you find. I didn't look too hard at mine but know the fixed cutter has become very sloppy and hitting the other cutter.

Having read-up at their web-site that would indicate knackered plastic bearings (available in a service kit for £19.50 + VAT where applicable. They claim that this is the only part that naturally wears out.

 

[pvb]

Having read-up at their web-site that would indicate knackered plastic bearings (available in a service kit for £19.50 + VAT where applicable. They claim that this is the only part that naturally wears out.

The claim is true - there's nothing else to wear out. If you ignore the wear on the plastic bearings for long enough, the cutters could clash, causing damage. Otherwise, the Stripper is excellent, well engineered, very effective.

 

[john_morris_uk]

Agreed. Ours jumped out and eventually I tracked it down to wear in the plastic bits.

A few £ to Ambassador and its back to being fine again.