Jocalia’s Windlass

Peter C writes…

After 22 years of service, the casting holding Jocalia’s windlass motor gearbox assembly in the forepeak cupboard cracked and failed. The boat was still serviceable as the anchor could still be deployed and retrieved manually, just like in the old days. This allowed Jocalia to continue her cruise while the bosun team came up with a repair plan. This plan included options that varied in complexity from simple (do nothing until she returns), through interim (a motor replacement) to complex (a complete windlass replacement).

We settled on the middle road in terms of cost and expediency and a replacement motor/ gearbox assembly was purchased and shipped to Northern Ireland. As a long term resident of the area, Antony, who was on his skipper checkout on this trip, contacted a friend with a boatyard in Strangford to receive the DHL delivery. 

As the replacement was an exact match, the work was straightforward but access was restricted by Jocalia’s fitted furniture so it was not possible to use anything other than hand tools. Also, the motor gearbox assembly was heavy and its centre of gravity was offset from the mounting bolts. At this point, a crane would have been useful! Only one person could hold the assembly in place while aligning the shaft and its key with the gearbox drive socket and align the gearbox frame with the mounting bolts, and then attach the nuts. 

We should have carried out the work in Belfast, the boatyard there has all the right equipment. Failing that. we needed a weight-lifter with three left hands. (Lewmar has obviously realised the difficulty posed by this arrangement as their latest design has a quick-lock clamp to hold the assembly in place while the detailed alignment is arranged.)

Significant points to note when planning for the future:

It is not possible to access the mounting nuts with a socket. A 13mm open or ring spanner is needed and the best option would be a ratchet. A torch and a mirror would be useful when reaching the nut that can’t be seen.

There is a dire warning supplied with the unit to ensure that the power terminals are held in place with an open ended spanner when tightening the electrical connections. This prevents the terminals being turned and twisting off the internal connections in the motor.

The two yellow wires are connected to an internal thermal sensor that goes open circuit if the motor overheats. These should be connected in series with the fuse on the foot switch power supply to prevent overload.

The motor is 700W and is capable of a pull of over 1000kg however it should not be used to pull the boat towards the anchor. If you need to leave quietly for some reason, tack up to the anchor and haul it up manually.

The new gearbox appears to include a lower gearing than previously so the chain is recovered more slowly and with better control.