Doing a lit bit of tinkering and want to take off the main crank pulley. It's either a bit corroded to the pulley or it's reverse threaded. Just wanting to confirm before applying any excessive force.

Cheers!

 

 

Fantastic. I'll use a little PB Plaster to loosen any corrosion and try again. Many thanks.

 

That sucked. Used a 15/16" 6 pt as it was a bit more snug that the 24mm. 15" breaker bar with 24" black iron extension and it was hard to break loose. My Jeeps hub at 240 lbs was piece of cake compare to this.

Rule of thumb is a new bolt but at $70+ is it worth it? Given the size hard to imagine it goes through a stretch at 50 ft lbs + 90deg. What do you suggest?

 

 

There was an audible SNAP as it broke loose. Just some adhesion. No corrosion on the mating surfaces. It threads in and out easily and appears to be in great shape. Largest bolt I've seen on the car so far in size and heft. Larger than the front sub-frame carrier bolts.

 

Typically torque spec that involve two step tightening where the second step is an angular amount means that there is some stretch.

 

bolts stretch when you torque them.. if you reuse that one you run the risk of snapping it when you decide to remove again.. or of it vibrating loose..

 

Thanks for the feedback. I get the concept but am trying to understand how it would differ from continuing to use chassis bolts or even lug bolts as each time they are torqued it clearly causes a stretch.
Maybe I'm not getting it and my penalty is to buy another bolt.

 

the problem.is that if that one backs off it can cause alot of damage.. if it breaks inside the engine the cranks is toast.. vs the chassis where u can always drill it out and put a timesert in..

torque to yield bolts are made to stretch.. that is how they clamp onto things.. once they stretch they will no longer have the same clamping force and will most likely fail..and since they are stretched they will likely eat the threads..

alot of people switch to arp head studs for that reason.. more expensive but you can re use..

 

Appreciate the lesson. That makes sense. Love this forum.
New bolt is on it's way. The cost of a good bottle of bourbon and wine to get it here but worth it. Just need to wait for the single digit weather to pass.

Cheers!

 

let others mistakes not be yours..jaja.. ive taken motors apart with bolts that where reused.. and that wasnt fun..

 

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Not always. It is just another torque specification that high end engines have. IF the book says that it is one time use only, then replace it. IF not, re-use it with a bit of Loctite.

 

Unfortunately I don't have a book but I did speak with a few knowledgeable resources and a great guy at RSS. It was the same from everyone, this bolt is a one timer.