Prop Shaft coupler loose at transmission

[rsmith]

Tapered fittings need to be extremely clean before assembly I would guess there was foreign material in the joining surfaces that worked it’s way out or it was binding on the key way and it finally seated. Unlikely the nut came loose. Impact gun can drive the coupling so far up the taper you could split the coupling. Over tightening tales away from the residual strength the fastener has to do its job. I’d split the coupling in 10 hours and check the tension of the nut. You shouldn’t need a diver for that

 

[Eddieclemons]

She was definitely clean this time. I would definitely feel better taking a peak after 10 hours as you recommended. Thanks

 

[rsmith]

I’m just going through this with a prop on a 37 Hatt I take care of for my neighbor. Went to the yard Monday and saw one of the shaft nuts loose. Of course the nut wasn’t loose the prop had worked its way up the taper and pulled away from the nut. The yard changed the props 2 years ago and I can guarantee they weren’t seated correctly. It’s a lost art now but when I was a kid I used to watch people seat the props by taking the key out and spinning the prop on the shaft with grinding powder between the hub surface and the shaft. Seat’s everything and gets rid of hi spots.

 

[Captain Ralph]

I’m just going through this with a prop on a 37 Hatt I take care of for my neighbor. Went to the yard Monday and saw one of the shaft nuts loose. Of course the nut wasn’t loose the prop had worked its way up the taper and pulled away from the nut. The yard changed the props 2 years ago and I can guarantee they weren’t seated correctly. It’s a lost art now but when I was a kid I used to watch people seat the props by taking the key out and spinning the prop on the shaft with grinding powder between the hub surface and the shaft. Seat’s everything and gets rid of hi spots.

That is still the way to mate props and couplers.
Still have tubes of lapping compound in a box around here somewhere.

Lost art or laziness? Both?

In this adventure, I just hope the coupler was fit properly originally and will lock together correctly now.

 

[bigbill]

i still do my props that way

 

[Bob Bradley]

It's the right way.

 

[jim rosenthal]

Good luck with all this and I hope your trip goes well.

 

[Eddieclemons]

Well I have returned from my trip which was a little over 200 miles. We ran about 2.5-3 hours at 21knts@1900 and about 15ish at 9knts@900. Burned about 300 gallons or less. I hope to pop open that coupler and check the nut asap. I do plan on getting a replacement first.

 

[Eddieclemons]

Coming Home from Cordell Hull Lake to Old Hickory Lake

 

[Eddieclemons]

Winding scenic river run with one lock.

 

[Eddieclemons]

On the lock wall and dock with some running partners. And yes, the Princess with a C-18s was back in the barn a few hours before me. The gas Monticello houseboat is more my $peed.

 

[johnjen50]

Yeah but your boat is soooooo much cooler!

 

[jim rosenthal]

You poor guy, having to run in all that clean fresh water.
Sounds like the shaft coupler behaved itself.