God hates me and my boat

[oneti mofugus]

Well...maybe not, he's been pretty good to me in life. But I am having some rough luck with my boat. I won't go through the previous issues I had, as they are resolved.

Anyway, I roasted my previous outdrive, and purchased a new SE106 from SEI. It came, I installed it, added a brand new diamond 4 prop and hub kit, and took her out for the break in period. Ran like a champ for the first 3 hours, saying in low rpm, varying the speed, running in reverse a little, everything I'm supposed to do, by the book. Everything was running very smooth, no noise, no excess heat, all perfect. I had slowed to about 1800 rpms and started to come about, and I heard and felt a loud clunking, and immediately back off into neutral...I killed the engine and drifted for a minute or two. Started back up in neutral, no sound or vibration, but as soon as I pulled it into gear, it would run, but shudder pretty significantly. Killed the engine again, brought up the drive, and the prop was damaged on 3 of the 4 blades, nothing huge but def a ripple or two on the edge of one blade and chewed up the edges of the others. Thats when I saw a tow rope handle (not mine), all shredded, about 10 or 15 feet from my stern, so I am pretty confident I nailed that sucker.

Limped back to shore, pulled the boat out, nothing entangled or caught in the prop, no other damage that I could see. The only difference I noticed is that the ratcheting action of the prop, while in forward gear, was somewhat easier than before the incident. In reverse, the pressure required to spin it in the ratcheting direction was the same as before the incident. I pulled the prop and inspected the hub, and it was undamaged, as well as the splines. So I guess my question is...what the hell did I break? What part of the driveline absorbs the shock of something caught in the prop...what is unbalanced now that causes the shudder?

I have since pulled the drive off, the coupler, gimball bearing, u joint, and upper unit appear fine and spin freely with no noise or roughness...so my current supposition is that something got messed up in the lower unit. Any thoughts are appreciated.

 

[JustJason]

Re: God hates me and my boat

I pulled the prop and inspected the hub, and it was undamaged, as well as the splines. So I guess my question is...what the hell did I break? What part of the driveline absorbs the shock of something caught in the prop...what is unbalanced now that causes the shudder?

and the prop was damaged on 3 of the 4 blades, nothing huge but def a ripple or two on the edge of one blade and chewed up the edges of the others.

Uhmm... you broke your prop. They are perfectly balanced out of the box. There's really no such thing as "nothing huge" when it comes to prop damage. They aren't cars, and don't just have "fender benders"
If 1 of the edges is chewed even a little, the whole prop is now out of balance, and would explain your vibration issue.

The other thing you have to check is the propshaft itself. They can get bent after impacts, and will also cause vibrations.

 

[oneti mofugus]

Re: God hates me and my boat

Thanks for the advice....I kinda knew about the unbalanced issue and vibration but I just wanted to play dumb and a get first impression or two. I did NOT think about the prop shaft, so I will def check that. thanks again

 

[JustJason]

Re: God hates me and my boat

but I just wanted to play dumb and a get first impression or two

No need to play dumb my friend. There's enough of that here already to go around for everyone.

With the boat in the driveway (and hooked up to a water source) pull your prop off and run the boat, shift it into fwd gear. If you can see any runout at all then your propshaft needs attention. Good news though, being an SEI drive, you may get them to cover it (sans shipping and new gear oil) under warranty.