I have a externally balanced 540 Gen VI motor. Found a crack in my harmonic balancer and was wondering if anyone knew if the 454 mag externally balanced balancer was the same. In the Mercruiser Parts it list the same number.. Some years of the 502/540 are internally balanced.
I know that my motor is externally balanced.
All help appreciated

Sheikman

I am not sure about the balancer, but there is a deference between externally and internally balanced. don't mix them up. also if you didn't already know. a 454 and a 502 both use the same crank shaft and are usually externally balanced.

Sheikman,
Check out :www.paceparts.com they will have the balancer at a considerable savings. The chevy part #10216339 is for a GenVI externally balanced 454 or 502, it's $103.90 at Pace.
They are a good source for certain parts, but they are not boat people!
The balancer is the same on either marine or non marine applications.
Another thought and this is what I did , add a FluidDamper, much better way to go and you will pick up a couple of xtra horses due to less harmonic vibration in the motor.
They can be had from Jeg's for about $315.00 catalog #388-712105-002.