BHJ harmonic balancer problems

DemonSC

Registered User
i bought a BHJ balancer and tried putting the crank pulley on and they wholes wouldnt line up right and broke off 2 bolt heads, is it suppose to go on a certain way?
 
If you are re-using the stock steel pulley set on your new BHJ balancer, I hope you had it re-balanced - because their original balance was based on the old stock assembly.
 
um I dont know about S/C's but on my 3.8 cougar the holes are not uneven also it has a thunderbird harmonic balancer because I stripped the threads in the stock one ,it should go on in any position did you get the snout inside on the balancer reground to match your crank? on mn12performance.com it says you have to
 
hmmmm no i just threw it on there, can i take the pulley to a machine shop or where can i get it balanced, and how much do you think it would cost?


-Chris
 
my engine is pretty much stock would that mess up anything? i got 173K on the motor, im trying to get my car running as fast as i can but i want to do it right. I havnt had a car in 7 months and this car is my DD
 
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No it won't mess anything up...it's one of the first mods I did to my car. Alternator and Waterpump will turn a little slower, but not enough to cause any problems, unless you have some huge audio equipment.

David
 
would i have to buy a belt with it as well? I see that spinning wheels has two different crank pulleys i should buy the "regular" one and not the 10%?
 
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No belt length changes required with underdrives.

I have no idea what is required to use the crank pulleys sold by Spinning Wheels...best that you talk to Victor about that.

David
 
what places sell the underdrive pulleys? haha nevermind i found them
 
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Nub here - Whats the deal with SC's & harmonic balancers? Do they go bad or break? I've seen a few posts talking about them cracking, I would think that would only happen if you didnt use a puller properly upon removing it or something. Please advise.
Thanks
ALR
 
Nub here - Whats the deal with SC's & harmonic balancers? Do they go bad or break? I've seen a few posts talking about them cracking, I would think that would only happen if you didnt use a puller properly upon removing it or something. Please advise.
Thanks
ALR

They have an aluminum hub...when the elastomer gets dried up and starts falling out, the imbalance causes the inner hub to break. Usually the head of the bolt holding it onto the crankshaft breaks off too. Removing and reinstalling the balancer during repairs will cause the fit of the hub against the crank to be looser that it was originally, because the aluminum is softer and conforms to the shape of the crank snout. The fact that the supercharger is driven off the crank also adds additional stresses on the balancer.

The BHJ balancer has a steel hub that is much stronger and holds it shape.

David
 
some of them crack so it's wrote ,some break -it's a throw away part unless your lucky ,that makes every-one happy . have'nt had the pleasure of that yet

steve
 
Thanks guys - now I understand. It wouldn't be so bad if the BHJ balancer was a simple R&R job but having to get it machined to fit kinda sucks. Must be a real pain to get the broken bolt out of the crankshaft! Don't even want to think of that.

Arnold In The Smokies
 
Thanks guys - now I understand. It wouldn't be so bad if the BHJ balancer was a simple R&R job but having to get it machined to fit kinda sucks. Must be a real pain to get the broken bolt out of the crankshaft! Don't even want to think of that.

Arnold In The Smokies

I didn't have to machine my BHJ it went right on.Yes getting the broken bolt out of the crank is no fun.
 
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