spun prop hub, or bad coupler... how to easily tell the difference....or can you?

ScottinAZ

Senior Chief Petty Officer
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Jun 25, 2009
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ok, went out to the lake this morning, ready for a morning of enjoyment and boating. Pulled off of the dock, got up to about 3200rpm cruising speed and all was well for about 5 minutes, then the RPM took off, and the boat dropped off plane. No obvious sounds from the engine bay, and no smell of burnt rubber. Popped the boat out of gear, and have both forward and reverse, just not at anything over "idle" speed. RPM will go up, with no increase in speed.

First thought was the coupler went belly up, but then I remembered I had changed out to my spare prop after last trip. This prop came with the boat and to me is unproven. Is there an easy way to tell which went pear shaped on us this trip?


Couple of added notes here. Once back to the dock, I raised the drive, waded back to the prop and with the engine off (and battery secured) put the boat in both forward and reverse. I can relatively easily spin the engine over through the prop in both gears. There was no noise when the engine revved, save for the engine revving. No off smells or smoke was noted. I popped the engine cover when we were back on the trailer and looked at the coupler, and there is no signs of discoloration, nor rubber crumbs from slipping. I can easily idle around in gear all day long, I just have no "go" when I feed it the beans, the engine revvs, and nothing else of note happens. I didnt have anything to mark the prop with to see if it is spinning relative to the mounting nut, so I dont know which rubber piece ruined my Friday......
 

JASinIL2006

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Post #2 in this this thread explains how to check for a spun prop hub:

 

ScottinAZ

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Jun 25, 2009
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Post #2 in this this thread explains how to check for a spun prop hub:


that sounds EXACTLY like what I had happen...... Yay, blown trip caused by my own hand changing something that "wasnt broken"...... well, if it aint broke, fix it till it is......
 

ScottinAZ

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Jun 25, 2009
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well, we have a confirmed kill...... Whipped off the prop nut, and this is what I found.... thrust washer mating face SHINY BRASS (was tarnished when installed).... and a fresh "ring" on the lock nut side..... again, not there when installed. Ladies and gentlemen, we have a spun prop hub......

Does anyone know of a good "online" prop shop to send this to. We dont have one locally, and I doubt even in the Greater Phoenix area there is one. We have become a throwaway society, but this prop is good except for the hub.....
 

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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The two prop shops I know that rehub are green bay propeller in suamico Wisconsin and general propeller in Bradenton Florida. Most prop shops ship to general propeller
 

ScottinAZ

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Jun 25, 2009
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742
Cheaper to buy a aluminum one online than repair it .
I figure a couple of emails are cheap, see what they have to say. Im already picking up a spare MW on ebay for a good price. I wont leave the dock without a spare now......
 
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