On departing Charlotteville, Mick noticed a new squeaky like noise eminating from the engine compartment. On investigation we noticed the engine was wobbling around rather alarmingly on its mountings. We were not under power, but sailing with the engine in neutral and the propeller shaft turning as per the instructions in the Gearbox manual. This always creates an audible noise, but it is possible that the noise levels had increased without us noticing until Mick detected the new noise.
I've never had cause to study the behaviour of the engine when sailing before and so wasn't certain whether what we were observing was normal or not. To be on the safe side we decided it would be best to put the engine into reverse as this was not explicitly prohibited by the gearbox manual.
Finally, the day before we were due to leave Soufriere, we inspected the engine mountings and found that two of the four - front and back, diagonly opposite eachother - had worked lose.
Forward port mount
Aft starboard mount
The locking nuts on both are under the red 'feet' and clamp the engine/gearbox up against the top nylock nut so it's aligned with the propeller shaft.
The top nuts of both of them appeared to have unwound on the engine bolts' threads. Fortunately however, Mick spotted that they were nylock nuts and therefore were very unlikely to have moved. What had actually happened was that the nuts underneath the engine feet had worked lose and had dropped down the engine bolts!
Both of the bolts and their nuts were quite difficult to access, with very restricted space in which to engage a spanner. It was therefore a slow laborious process to tighten the nuts.
Once finished, I then noticed that all four of the bolts connecting the gearbox's flexible coupling to the prop shaft were also lose and so those too had to be tightened up.
The flexible coupling is the yellow plastic disc visible behind the gearbox.
All in all, the job took most of the day but it was a big relief to have discovered the problem and to have resolved it before any damage was done. As far as we could tell anyway! 🤞🤞🤞
On our subsequent passage up the coast to Rodney Bay the engine was far more stable and the noise of the propeller shaft turning was significantly diminished.
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