Harmonic Balancer Failure

[zimmstoy]

Hey everyone,

I ran the 87 Camper Special 454 truck today had it cruisin pretty fast. Came home and parked it, shut her down and heard a horrible noise. Sounded like the flywheel broke in half. After further inspection i found that the weighted part of the harmonic balancer (the piece with the timing mark) actually separated from the balancer. It is rattling around pretty bad. Needless to say I need to replace it. Has anyone had this happen before? Is it as simple as a separated balancer from the weight or is there something deeper I should be looking into?

I was running the truck today around 85mph with the turbo 400 in there I suspect I was going around 4500-5000 rpm (is this a bit much for a stock balancer? Anything I need to look for in a replacement balancer?

[dammitmitchell]

the harmonic balancer is basically glued (vulcanized IIRC) to the center piece with rubber
over time they will wear out and separate.

just replace the balancer, and good luck

[zimmstoy]

Thanks I will get on that. Should I just replace with a stock replacement or is there any reason to upgrade or put a performance upgrade on it?

[dammitmitchell]

i wouldnt unless your trucks suped up a bit.
im running a stock balancer on mine still. but measure the size across because there are multiple options for balancer size

[spudz]

spinning that big block at a constant 4500-5k.....you will have alot more then a balancer failure in your future....

[old Rusty C10]

ive had several of these go out on older vehicles over theyears... one happened while pulling the wheel off to do a timing chain.. didnt notice it had broken some until i fired up the motor ....i wouldnt go hi performance on one of these for a regular motor like the other poster said