Johnson 1957 18hp Flywheel Problems

[mr-asa]

Gentle heat and some WD40 around the crank so it seeps down?

[retiredoz]

Hard to tell, but doesn’t it look like the flywheel nut is still in place ?

[Steve A W]

It’s a good idea to use "Grade 8" bolts with that type of puller.

Steve A W

Member of the MOB chapter.
I live in Northwest Indiana

[wedgie]

You can burn the coil(s) if you use too much heat.

I made a plate out of 1/4 inch steel to support the bolts on the harmonic puller.

The plate helps keep everything pulling evenly. If you have a recoil ratchet like the one pictured use it as a template to get the hole spacing.

I had a heck of a time getting a flywheel off of a 33 hp a while back, and I found the plate really helped keep the grade 8 bolts pulling squarely.

[opposedtwin]

quote retiredoz:

Hard to tell, but doesn’t it look like the flywheel nut is still in place ?

indeed it does. are you sure you removed the flywheel nut? it has to be removed, not just loosened. I have made this mistake myself more than once.
scott

EDIT: LLOYD IS CORRECT. SEE HIS POST BELOW. THE FLYWHEEL NUT MUST BE LOOSENED, BUT NEED NOT BE FULLY REMOVED . SCOTT

[scoot]

Also tapping from underneath the flywheel with a plastic mallet is effective.
I wouldn’t remove the flywheel nut completely. Helps to keep the whole assembly
from flying off when the pressure releases. Patience and pressure.

[lloyd]

1)Do not remove the flywheel nut completely. Just loosen it to near the top of the crank threads. I have seen flywheels pop 3 feet into the air and then fall 7 feet onto the ground when no flywheel nut is on the crank. Not a good thing.
2)Those three stove bolts are too long. They will stretch under tension. Shorter grade 8 bolts would be better.
3)Also those three bolts have no way to thread them deep into the flywheel. Hex bolts would be preferred. Bolts should be threaded evenly ALL the way into the aluminum threads of the flywheel. You definitely do not want to strip the threads out of the flywheel. Seen that too many times.
4) As Frank said, after it is set up correctly, just torque that center bolt as hard as it takes. It WILL pop. Heat around the center hub can help but it is rarely if ever needed.

[jerry-ahrens]

Agreed. I think your bolts are too long. The shorter the better. Go with hardened bolts as you will most likely break the softer ones.

[Randy in Tampa]

I use bolts with heads on them and washers so I can tork them down individually after I tighten the main puller, working each one little by little always works and don’t be afraid you’re tightening too much those 18hp flywheels can be a pain in the neck to get off sometimes, oh and spray the taper with kroil or PB blaster… 😎

[rschiff]

Thank you for all the detailed advice/help.

I will get the shorter hex bolts, grade 8 and then try again. I have a whole new respect for tapered fit!

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