Harmonic Balancer / Crankshaft Threads

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norm86chevy

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Ok so I used a puller to take my harmonic balancer off but the pulled didn't have the little cone on the end of the bolt me being a newb I didn't pay attention to it and it messed up the first couple threads where the harmonic balanced bolt goes. Someone please tell me I can fix this and how:banghead:
 

f1shman

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It sounds to me like you'll need to run a 7/16-20 tap into the crankshaft to clean up the threads.

FYI: The next time you have to pull a balancer, take the balancer bolt out and remove the large washer from it. Thread the bolt back in the crank all the way after and you'll be able to set the puller against the head of the bolt without having to worry about the threads.
 

norm86chevy

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Never thought to put the bolt back in Ik a dumby
 

crazy4offroad

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That crank is hardened steel so it probably didn't mess them up too bad, just be sure to use plenty of oil on the tap when you go to re-tap the threads. If it doesn't seem like it will start take a rat tail file and very carefully dress those first couple threads out a little so the tap will start.
EDIT: also, I wouldn't use a bottom tap for this.
 

Swims350

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what about a thread chaser or just using the bolt to see if it'd thread? I did the same thing just put the bolt back in, worked for me.
 

norm86chevy

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When I try to put the bolt back in its Trys to start crooked
 

f1shman

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383 combo

A tap sounds like the best bet. You could always use a helicoil or run a different bolt size if the threads get too loose.
 
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HotRodPC

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How are you doing on this Norm?

Hopefully you are still subscribed to the thread cuz if you're looking for the thread titled HELP, its gone. I changed the title to make it easier for members to find it in the search feature.
 

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