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Sheering flywheel keys in b73 Johnson 135hp

G

gary

Regular Contributor
" I have a 135 hp johnson and

" I have a 135 hp johnson and when I bought it, it have a sheered woodruff key in the flywheel. I've since replaces it 2 times and I keep sheering it. Yesterday I took the boat out all day with no problem and when I came back in to the dock, I idled up to the dock and soon as I went into neutral it died, couldn't start it back. Got back home checked the firing , no fire. pulled the flywheel and sure enough sherred another. I'm putting the 105lbs of torgue on it as instructed. Is there different grades of woodruff keys, (harder) on the market and maybe I'm using to soft a key?
The motor runs like a top,doesn't miss or try to backfire, and starts real easy.
Any thoughts or suggestions is greatly appreciated.
thanks in advance
Gary "
 
I had the same problem with a

I had the same problem with a lawn mover engine. It would shear keys left and right. I also looked for harder keys and could not find anything harder. It turns out that the key I was using was just a hair to small leaving the sligthest amount of play. Make sure the keys you are getting fit tight. I had to force my last key in with the nut on the crank and it has lasted for several months now.

Hope this helps.
 
I had the same problem with a

I had the same problem with a lawn moWer engine. It would shear keys left and right. I also looked for harder keys and could not find anything harder. It turns out that the key I was using was just a hair to small leaving the sligthest amount of play. Make sure the keys you are getting fit tight. I had to force my last key in with the nut on the crank and it has lasted for several months now.

Hope this helps.
 
Thanks for the reply...
the

Thanks for the reply...
the keys I've been using fit tight and usually have to be tapped in. I was also told today that a off balance flywheel can cause the keys to sheer. The flywheel that's on there seems to be a little off balance and has a noticable wobble when trying to start the motor. Could that actually be the problem?
thanks again
Gary
 
Are you replacing the key wit

Are you replacing the key with one from the hardware store or the factory original part? there is a difference.It may help to lap the bore of the flywheel to the crankshaft. The key locates the flywheel but the taper drives it.The correct fit and torque are important.
 
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