Flywheel, crankshaft

[alanp]

i know better but did it any way, now I have a problem. I had the flywheel puller on and the flywheel still wasn’t coming off so I whacked the top of the flywheel puller a couple times with a hammer.
Now the flywheel nut doesn’t go on the crankshaft. With the taper of the puller it must have expanded the threads on the crank a bit.
Before I ruin it further do you guys have a suggestion? I was going to try and run a die chaser on the crank threads?
What really ticks me off is I use the double nuts as suggested on this site all the time and it always works. I had them sitting on the bench but thought I would just give it a couple good whacks on top of the puller. Also I still can’t get the flywheel off.
Alan

[frankr]

That is a subject I’ve often wondered about, but hardly ever see it mentioned. Yes a puller with a pointed center bolt can expand the crankshaft if hit hard enough. That is just one of the reasons I keep preaching not to belt it with a sledge. An ideal puller (like the OMC) has a flat end on the center bolt, with only a small point to keep it centered on the crank. The flat contacts the crank end before the point goes deep enough to do damage.

What to do now is up to debate and opinions. The threads are hard and difficult to fix. And of course if the nut is hard to turn on, it defeats the benefit of using a torque wrench to tighten it properly.

[chris-p]

Always Always Always leave the nut on when removing a flywheel with the puller!

I have repaired minor damage on the threads with a thread file followed by a die chaser. Depends on the damage the threads have undergone.

Post some pics.

[alanp]

The threads look perfect. I think o.d is just expanded a bit by the taper of the puller.
Alan

[dave-bernard]

sears makes a cool tool for just that problem and not that much $$$$ worked for me. works on all thread sizes.

[crosbyman]

sears….? R.I.P.

Joining AOMCI has priviledges 🙂

[dave-bernard]

craftsman external thread repair tool. go to the sears site and look it up just under $30.00 well worth it works great. just looked it up.

[1957evinrude]

quote Chris_P:

Always Always Always leave the nut on when removing a flywheel with the puller!

I have repaired minor damage on the threads with a thread file followed by a die chaser. Depends on the damage the threads have undergone.

Post some pics.

That’s a good idea.

[westwind]

Emery cloth strip around the top of the crank should help if it’s not mushroomed too much, kind of a manual reverse belt sander. Should keep it fairly round vs trying to grind/dremel/file it.

[The Boat House]

You might try taking a straight edge like a 6"
machinist ruler and lay it on the threads to
see how much they’re pushed out. You can go
around the crankshaft with a file to remove
the high spots. When you get the ruler to lay
flat on the threads all the way around your
die should fit on and you can clean up the
threads.

[Author]

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