help harmonic balancer is twisted

[illregal82]

i just had a freind change my timing cover and gasket beause it was leaking and when he pulled off my balancer it looks like its twisted there ripples in the plastic crap in the middle . i was looking on ebay and alot of them say there for internally balanced not quite sure but i think that means your engine has to be blueprinted and balanced right? i need a oem style right ? what size 6" 6 3/4" please help

 

[elcaminokyle]

Your harmonic balancer is made of an inner hub and an outer hub with a rubber ring in between. When the rubber ring gets old enough it looses it's grip on the outer hub. This makes it possible for the outer hub to slip. When mine crapped out the outer hub went towards the timing cover and made a groove in it. I just bought a new one. The externally balanced harmonic balancer is for the 400 small block chev. It has a weight in the balancer and the flexplate/flywheel. All the other sbc engines use the internally balanced balancer.