Flywheel stuck to crankshaft!!!!
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Cruising
Joined: Dec 2018
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Flywheel stuck to crankshaft!!!!
I started a clutch job last week and got down to pulling the flywheel in the first few hours only to find out 3 of the 6 bolts have stripped heads. I tried everything I could think of to get the bolts out. I tried the chisel and hammer method, impact gun, impact chisel, air hammer with a chisel, heat, cutting a slot in the head and using a screwdriver to turn it over. Nothing is working so I finally broke down and grinded the heads off the bolts, as I did not feel comfortable trying to drill out the the bolts. Now the flywheel won't come off. I tried to use a pry bar on each side to pry it off. I've also tried heating the flywheel and then spray penetrating oil to help get some lube on it. If it helps its an aluminum flywheel.
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you probably melted the bolts to the flywheel when cutting the bolt heads off so that's why it won't move... I would try using a drill bit slightly larger than the bolt diameter and drill them from the ends until the flywheel is free, I'm also assuming your flywheel is already trashed from cutting the bolt heads off anyway and any further damage is moot at this point
Acct Suspended APR 2026 by request
Joined: Dec 2010
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Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
the flywheel isn't threaded so if the bolt heads are gone it should slide off, I just think the bolts and flywheel got fused together when cutting the heads off
Burning Brakes
Joined: Dec 2017
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I was going to say, what new crank are you planning to buy and who is going to rebuild your short block. But an entire new short block also works 
I'm sorry OP, I shouldn't be making a joke of your misfortune. My next step would be to start drilling and get yourself some really nice easy-outs. Unfortunately, all the heat cycling/hammering/prying you've done thus far has most likely toasted your rear main seal and probably damaged the crank bearings. Not to mention potential damage to the actual crankshaft.
Best of luck with the repair. Sounds like it may be a costly one.
I'm sorry OP, I shouldn't be making a joke of your misfortune. My next step would be to start drilling and get yourself some really nice easy-outs. Unfortunately, all the heat cycling/hammering/prying you've done thus far has most likely toasted your rear main seal and probably damaged the crank bearings. Not to mention potential damage to the actual crankshaft.
Best of luck with the repair. Sounds like it may be a costly one.
Last edited by wscott62893; Jul 23, 2019 at 01:28 PM.
Le Mans Master
Joined: Jan 2001
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From: Hilton NY
It might take a week of heating/oiling two or three times a day to free the flywheel, dissimilar metals in contact for a long length of time can experience galvanic corrosion which freezes the parts together. I had a large steel locknut in an aluminum outboard motor lower unit that took several weeks of heating/oiling before it was freed. Focus the heat on the aluminum flywheel because that will expand more than the steel and minimize damage to the crankshaft and seals.
Last edited by Fast one; Jul 23, 2019 at 04:15 PM.
