Johnson Flywheel with a stripped puller hole

[Buccaneer]

Wanted to pop off the flywheel on the RD Johnson,
but found out that one of the 1/4" x 20 puller bolt holes
is stripped out. Ran a tap through it to clean it up,
but it’s shot. Thought of extending the bolt in far
enough to put a nut on it, but the bolt hole appears
too close to the flywheel hub.
What are my options to get the flywheel off,
and repair the threads?
Have you been successful using a heli-coil on these flywheels?
Thanks.

Prepare to be boarded!

[auldscott]

If you are thinking of tapping for helicoil, perhaps just tap 5/16-18. Have not had to do this myself.

[jerry-ahrens]

Yes, you can install a 1/4 helicoil insert to fix that. If done correctly it will be stronger than original. Drill carefully… If you go with 5/16 you will need to drill out the recoil plate that bolts to the top of the flywheel. Since it’s made for 1/4 inch bolts, the 5/16 won’t fit. The problem is that part is super hard, and a regular drill bit won’t touch it. I have one on a Big twin that I need to drill out myself.

[Buccaneer]

Thanks for the replies. Jerry, are you saying the "ratchet" that the
starter pawls engage in, is hardened metal, or the flywheel?
I can’t remember what size drill bit is required to install a 1/4"
heli-coil. Not sure if one can drill out the old threads in a 1/4"
bolt hole, and still have enough "meat" to tap for 5/16′.
Will look tomorrow and decide the best way to go.

Prepare to be boarded!

[outboard315]

Have you tried the double nut bolt and hammer trick. No puller needed.

[rudderless]

A tap drill for 5/16 is 1/4 I think. A dremal or die grinder will open up that starter cup no problem. Them I’d tap the others 5/16 for balance and symmetricy once the wheel is off.

[nj-boatbuilder57]

tap drill for a 5/16"-18NC is a letter F. 1/4" is close, but if you want to tap perfectly, F is the way to go.

[Buccaneer]

I’ve never tried the "nuts and bolt" routine on a bigger motor
before….. guessing the bigger they are, the harder they "pop" off.
I have no "letter" drill bits for some reason. Looks like they are .257.
Will look it over in the AM.

Prepare to be boarded!

[jerry-ahrens]

quote Buccaneer:

Thanks for the replies. Jerry, are you saying the “ratchet” that the
starter pawls engage in, is hardened metal, or the flywheel?
I can’t remember what size drill bit is required to install a 1/4″
heli-coil. Not sure if one can drill out the old threads in a 1/4″
bolt hole, and still have enough “meat” to tap for 5/16′.
Will look tomorrow and decide the best way to go.

Right, the ratchet, couldn’t remember the correct terminology. That thing is very hardened. Make sure you drill to the correct size…. an auto parts store will have the right drill bit. Otherwise you will pull the Heli Coil right out.

[fleetwin]

I’m confused, can’t you just remove the starter pawl ring and inspection plate cover, then drill the flywheel??

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