Flywheel key

[lifes great]

Does anyone know where I can get the right fly key for a 1960 Johnson 40 HP? I have the part number if needed, all the local shops don’t want to be bothered on a small item. I’m getting tired of making my own and they just don’t hold up too long. Key (307480) engine (rds-22)

 

[Paul Moir]

Re: Flywheel key

Try Mastertech. <br /><br />There's a little groove carved into one end of the OEM key. That groove must face down when you install it. I have no idea why.<br /><br />You've probably heard it before, but you must torque the flywheel nut to exactly 105ft/lbs if you don't want your key shearing. When a key shears, sometimes you must lap the flywheel to the crank to remove imperfections. Simply use a little valve grinding compound between the two, and give the flywheel a couple turns by hand until any high spot is ground off. Then clean the taper perfectly. The hub and crankshaft must have no grease or oil on them, because if they do the hub will spread when the flywheel nut is torqued and may break.<br /><br />I wonder why your keys are breaking, even though they're not originals. The key's work should be done when you torque down the flywheel - it just indexes the flywheel. The taper is supposed to hold the flywheel to the crankshaft.<br /><br />Good luck!

 

[rickdb1boat]

Re: Flywheel key

Try here:<br /><br /> web page

 

[lifes great]

Re: Flywheel key

I think you just answered my question. As far as anything inside the engine causing the key to shear-off I don’t think that’s it. However the first two that busted off was that I didn’t torque it down enough. Then like a dummy I put grease on it. It’s not bad when they bust off at home but not too great out a few miles in the gulf. I never remembered any engine that was as critical with the keys. If I could get the right one I’d get a bunch of them. Thanks for the info.

 

[lifes great]

Re: Flywheel key

Rick, thanks for the link I just emailed them.