Olds 215 4bbl....Having a hard time getting a timing setting that will give

me a good idle speed.Have slightly larger profile cam than stock.Timing

check shows timing advanced beyond the tab on the engine,Vacuum

advance disconnected and plugged.The engine seems to want to run

better at this setting,but don't want to run it too far advanced and break

something.

Reliable source (D&D) says the harmonic balancer may have moved

on itself due to breakdown of the rubber vulcanizing between it's parts.

Is there a way to find out if this is what the problem may be with my

engine? Do these things fail (fly apart),or do they break down a little at

a time,changing the timing mark from it's original position?

Any help would be appreciated.Just had the engine rebuilt,and don't

want to break something now.

 

Only way I know is to determine TDC through the spark plug hole at #1, and see where the balancer reads.
Painstaking, but worth it!