Originally Posted by dpa99c
Thanks for all your responses guys.
Yep, they definitely have shear pins. But I'll try beamishken's idea and swap the props - surefire way to figure if it's the prop or the engine. Then I might come asking you again...
OK, I swapped the props and took the boat for a spin. Incidentally, I was wrong - the pins are split pins not shear pins - they just stop the nut that holds the prop on from spinning (see photo below). But the exposed centre isn't rubber, it's metal (as can be seen in photo)...???
Photo of prop
Anyway, swapping the props eliminated them as the cause of the problem. The same starboard engine is still showing the same symptoms, but worse now. By the time I turned the boat around to bring it back in after testing it, that engine is stuck in forwards gear (despite the position of the throttle lever which I can see is moving the gear shift on the outside of the engine casing via the cable) and the engine itself is not sounding 100% with a slightly metallic clicking sound. Hope I haven't knackered it by trying this
Any ideas again would be appreciated. I was hoping for a quick fix I could do myself as removing the engine or towing it along with the boat is gonna be a hassle and taking it to professionals is expensive....