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Crank Bolt Will Not Come off

B

BoilerTom

New member
So I'm doing a cam install with my brother and dad and we are stuck on this crank bolt. We have most of the top end of the engine off and the valve springs exposed. We've been hammering at it with a half inch impact wrench for a while with no luck. I've read about using the starter with a bar up against the frame, but when we hooked the battery back up and bumped the key, the starter didn't fire and gas started leaking (whoops) so, anyone have any ideas? how do you kill the fuel line and get the starter to actually fire? we've thought about applying direct voltage to the starter, which way does the starter turn the engine?
 


Fivefingerdeathpunch said:
Arent crank bolts reverse threads???

And just pull the fuel pump fuse.
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Not that I remember.

I had to heat the bolt up to get mine off. Other people say this is bad but I think if you replace the crank seal you should be ok. Just don't go nuts and heat the thing up crazy hot.
 


ok, took the flex plate bottom cover off, one person held the flex plate ring gear in place with a pry bar, shocked the bolt with a hammer, hit it with the impact and it came right off. also, the bolt is normal thread direction.
 
We were just about to hit the starter with some direct voltage, thankfully it didn't come to that or having to heat the bolt :)
 
Holding the flex plate is the best way. If you're alone next time a pair of vice grips takes the place of that person.
 


Bio248 said:
get a better impact.
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A while ago I may have said that same thing. However having a good impact and recently having a bolt fight to the point that I had to stand on the engine stand and have a neighbor put all his weight at the end of the 4 foot jack handle... yeah. I was surprised. Once in a while..you'll see a stubborn one. That was the first that my 600ft lb gun couldn't take off.
 
Have to agree with Bio a little. I recommend a good impact with not only high torque, at least 600 ft lbs and good vibration (ibms or ipms I think they're called) for regular bolt use. Also might have to bring up the air pressure to around 160 psi (make sure your fittings are rated to this, mine are rated to 200 psi). For that crank bolt though, think I remember having to use the 3/4" impact cause some jack*ss used too much locktite. The 3/4" is probably rated close to 1000 ft lbs, not recommended for smaller bolts lol.
 
RegalGS98s said:
HFor that crank bolt though, think I remember having to use the 3/4" impact cause some jack*ss used too much locktite. The 3/4" is probably rated close to 1000 ft lbs, not recommended for smaller bolts lol.
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I was using 150psi and the Ingersol 1/2 never gives a problem. This one time though....lol I wish I had a 3/4"
 
BillBoost37 said:
I was using 150psi and the Ingersol 1/2 never gives a problem. This one time though....lol I wish I had a 3/4"
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I have a Harbor Freight Earthquake 1/2 which is basically a copy of the Ingersol. For the first time taking that bolt off, I needed the 3/4". For my Honda Accord F22B1, everytime I take it's crankbolt off, I need the 3/4" impact or 3/4" breaker bar. I've broken three 1/2" breakerbars with that bolt and I i didn't even have a pipe on it. The Honda's bolt sounds like a gun shot when it gives way, lol. Don't know why it's so hard to break loose, it's not torqued that tight.
 
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For the record, we got the bolts off, it was a matter of holding the engine from rotating via the flex plate so the impact could drive its full torque into loosening the bolt. We were using a 1/2" drive shop impact wrench, very beefy.
 


Now imagine that in my one case out of a million 3800's I've worked on, one fought enough that with the flex locked up 600ft lbs wasn't enough.

Had to put the 1/2" long handle ratchet on it, then the 4 foot jack handle and have the 200+lb neighbor jump up on it while I stood on the engine stand and held the motor down. When the bolt broke free, we thought it broke in half. Came free though.

For everything we take for granted, there's one in that group that'll teach us a new trick.
 
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