Spun Prop/Engine Coupler - UPDATE

[dpoff]

I was was a few miles out of city park today and the engine over revved. I backed it down real quick to figure out what was going on. I picked up speed slowly and everything seemed alright and about the time I got to cruising speed, it did it again. I began thinking that I spun a prop. I could run 1500 rpm no problem. I also heard no gear grinding or anything like that.
As an after thought this was the first time that I had it out after having an engine coupler installed along with new engine mounts and engine alignment. Has anyone experienced a new engine coupler go? I`am not thinking that this would happen, what`s the chance? I pulled the prop and took it to a prop shop and they put a ginourmus torque wrench on it and showed me that it was not the prop. Any ideas?
This is a 165 Mercruiser w/ a model 1 outdrive.
Boat is a 24` Seabird.

 

[Bondo]

Re: Spun Prop/Engine Coupler

Re: Spun Prop/Engine Coupler

Has anyone experienced a new engine coupler go?

Ayuh,... While it's Possible,... It's also Highly Unlikely....

Scribe a line across the face of the prop,+ try it again, then see of the line still lines up....
I don't care How big the wrench was, it really means Nothing...

 

[sho3boater]

Re: Spun Prop/Engine Coupler

Re: Spun Prop/Engine Coupler

Most all drives I've ever seen only have a part that slips in the prop, otherwise it is broken and does not work at all. Definitely mark the prop to hub and check that, sounds typical that is what they act like. Just get a new one pressed into it. I had one boat I went around a lake a couple times wot and all the sudden it slipped and could only run half throttle, I doubt I hit anything.

 

[PitchFork]

Re: Spun Prop/Engine Coupler

Re: Spun Prop/Engine Coupler

Yeah spun prop Hub. I was trying out a 4 blade SS 14" x 19" on my boat Tuesday and ran for about half mile and all of a sudden dead in the water. I thought I had lost the prop because it is a Yamaha Prop Hub on a Mercruiser and had only the locking nut on and not a cotter pin. Anyway I was able to idle over to an island and put my 3 blade SS 14" x 19" back on and run just fine the rest of the day.

The 4 blade prop only was giving me 3,600RPMs @ 35MPH when the other prop gave 4,200 @ 43 MPH. I am going to try just for fun a 3 blade 14" x 17" SS Prop I should be getting b/w 4200 and 4600 RPM.

 

[dpoff]

Re: Spun Prop/Engine Coupler

Re: Spun Prop/Engine Coupler

UPDATE

I just picked up my boat from my boat repair shop.
The brand new coupler was bad. The repair shop called the manufactuter and they agreed to pay for new coupler and labor to change it out.
As soon as I left the lot I stopped at the boat ramp and tried it out doing a few high power hole shots and all is good.