Harmonic Balancer
 

I just replaced my timing chain, 150,000mi. In the process of removing the crank shaft pulley the harmonic balancer slipped and rotated on the pulley. I replaced the chain because the timing was off and well I figured it was a good investment after 150k. Engine shakes at low RPMs (< 2000) and feels rough at higher RPMs.
Question is - Does the harmonic balancer need to be balanced on the pulley? Is it possible my vibration is from this misalignment?

Thanks,

CJM

The harmonic balancer is keyed so you can't put it on wrong. The crank pully is perfectly balanced so it doesn't matter how you install it on the balancer.

I would double check to see if the harmonic balancer is on the crank shaft all the way, and you have all the bolts on the crank pully on tight. Any of these can cause vibration. I would also add a drop of lock-tite to the crank pully bolts just do they don't back out.

Did you put the timing chain on correctly (align the teeth right)?

The balancer only needs to be mounted (seated fully) completely. Other than that, as long as you are using the same balancer, make sure that its not coming apart (sometimes the outter ring separates from the inner ring, right at the rubber lining between them).

Problem fixed
 

Thanks for you posts. . .

cyberstang5.0 - Everyting looked tight and was. Pulley was secured fully. Took you advise on the lock-tite when I put the new harmonic balancer on last night.

drudis - Ya, I made sure I put the chain on correctly by double/triple checking before putting the cover back on. Good call though, that would have really S****. The lining between the pulley and vibration damber was seperating that's why it moved so easily.

Well, I replaced the Harmonic Balancer last night after work and it ran like a top. $100 bucks and 40 minutes. The balancer was new but, I could have gone to a salavage yard and pulled my own for probably 20-40 bucks.