Shaft broke off at the cutlass bearing

[Peter B]

I was just thinking that it had to be at least a bit of a surprise to the person operating the boat at the time.

Yes, I bet, but not as much of a ghastly surprise as I saw on the face of a newcomer to our marina the other day when I was down there. They had this new (to them) twin Bayliner, and were clearly a bit unfamiliar with driving a twin, and he was trying to back into the berth, as they feel they must if they have a twin for some reason. Anyway...to flick the stern to the right to clear the end of his finger, which was to the left of his stern, he put on too much reverse power to the port engine, and not opposed by putting the starboard engine in forward thrust, and it shot back and crashed into the stern of the boat in the adjacent berth. No major damage was done, and to his credit he reported it. (I checked)
I note he now cruises gently in bow first and with no dramas, just like most now do in our marina, as the fingers are plenty long enough for boarding by the swimstep.

Sorry, thread hijack over...

 

[Tony Athens]

Prop shaft failures

Just in case you want to think about a different very possible answer as to "why"....................................For the past 30 years dealing with these "unknown failures" this is what we have seen most shaft failures result from right at the beginning of the taper ........A poor install of the prop and key and /or keyway / proper fitting, it eventually comes loose, and the results are obvious.......I will offer one more thing to think about-- I am a very a qualified engineer & machinist and understand this stuff from "top to bottom", both on paper and in the field.

Take that for what s it's worth..


Tony

 

[Baker]

I was just thinking that it had to be at least a bit of a surprise to the person operating the boat at the time.

Yeah it was. It was that girl captain again....haha. She recovered well and just jammed the thing into the slip bow first.