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I need to replace the ring gear on my flywheel but cannot seem to even
budge the six bolts holding it on. What's the trick?
I've even put a pneumatic impact wrench to them and no joy.

Any help appreciated

Mike

HEAT is your friend.

Someone buttered up the bolts with Loctite.

mm58 wrote: Sun May 18, 2025 8:51 pm I need to replace the ring gear on my flywheel but cannot seem to even
budge the six bolts holding it on. What's the trick?
I've even put a pneumatic impact wrench to them and no joy.

Any help appreciated

Mike

When I first did mine, my old-school pneumatic impact wrench was unable to break them free, and I had to borrow a stronger one and use a larger/shorter air hose. They should be on with thread-locker so they'll be tough. Heat (torch or induction) will help, but I can also get mine off cold with a Dewalt DCF899HB which claims 700/1200lb of torque.

Thanks for the info guys!

I put a two foot breaker bar on those bolts and was able to crack them free
fairly easily.

Fun stuff...!


Mike

Just be sure when you replace them you use NEW bolts. Those are supposedly 1-time use bolts. When you tighten them you tighten them to the torque in the book, and then you go another 1/4 turn to stretch the bolt. At least, that was my understanding.

You turn them 60-degrees past contact, not 90-degrees.

IMHO, the bolts are fine to reuse so long as you know they've never been over-torqued. If the bolts haven't haven't been taken past their elastic zone, I don't see why they'd be unfit for reuse.

I did re-use my OEM bolts.

And yes, pre-torque to 20Nm, then 60 degrees past that
which equates to one facet of the hex head.