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Stuck Flywheel

RGP

Regular Contributor
1972 40hp Johnson. Flywheel is stuck. Really stuck. broke a grade 8 bolt while pulling. Tried hitting puller center with 2 lb hammer while under tension. Tried heat from propane torch. Tried penetrating oil. Using a 1/2" air impact gun on puller.

I encountered one like this a year ago. 1970 40 hp Johnson. Eventually the puller pulled the flywheel off, but in the process left the entire center section of the flywheel still stuck to the crank shaft taper. Essentially the puller tore the flywheel apart. Had to saw off the remainder.

I really don't want a repeat of that mess. Any suggestions on what to try when flywheel removal goes really, really bad?

Thank you.
 
Power Steering Fluid is just another 'name' for ATF. Main difference is the ability to absorb/tolerate water.
To make it aoll work quicker:
Attach the puller and tighten down.
Heat up the flywheel with a propane torch close to the center.
Take a can of Freeze Spray and spray the crank shaft tap!!!
This will make the tap 'shrink' and makes it easier for the ATF to penetrate down.
Repeat several times if needed.
 
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How hard to hit is hard to describe. I am using a 2 pound iron mallet. I am beyond tapping at it. I would call it a medium hit. You think I should go near full on? I am afraid of damaging bearings or fracturing the carbon seal.
 
Freeze spray, that is a great idea! Thanks for all the ideas Gentlemen. Will report back in a day or two.

How hard can you hit before you hit to hard?
 
Freeze spray is a good thing to use. The surfaces you are trying to separate are not rusted together. The surfaces are tapered. The puller puts pressure on the parts and the shock of a hammer strike will loosen it.

I would not swing the hammer as if you were breaking large rocks into small rocks, but, hit the center of the puller hard. After you strike it see if you can tighten it some more. Repeat.
 
if all else fails and you tried haffimans procedure then just let it set a day or so with pressure on it....add a little more oil a couple of times...it may penetrate and just pop off the next time you try...
 
I am pleased to report that the flywheel is off. In one piece. It took 48 hours. ATF, heat, freeze spray, 2 pound hammer and 3 grade 8 puller bolts. It sat under tension for most of the 48 hours. It let go all on its own.
I refer to this as the Dockside Haffiman-Kimcrbr procedure.

Thank you to all respondents.
 
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