PDA

View Full Version : Harmonic balancer runout - what's acceptable?


dhardison
11-25-2006, 09:51 PM
When I had the 454 in my Nova I noticed that the factory balancer had a little wiggle to it. I thought it was the balancer, so I picked up a Fluidampr balancer, but it did the same thing. I guess it could just be the balancer, but it's off enough to physically see the balancer move when the engines running.

Since I'm tearing the 454 down I threw a dial indicator on the balancer to check runout. I know these aren't the correct "terms" to use but I found the "diameter runout" was 0.010" off at worst (as shown here):
http://www.danhardison.com/454teardown/DSC02918.JPG

"Lateral" runout was 0.015" off at worst (as shown here):.
http://www.danhardison.com/454teardown/DSC02917.JPG

Do these measurements seem abnornal?? I'll throw the dial indicator on the crank snout itself when I get the chance to see if it's the crank or the balancer.

Thanks,
Dan
dhardison
11-26-2006, 08:06 AM
ttt
Rick Dorion
11-26-2006, 08:28 AM
Dan, are you sure it's the balancer? With my ATI I don't see any runout.
parsonsj
11-26-2006, 09:33 AM
Dan,
Is the runout from the crank end? Or is the balancer not "square" to the crank?

The boys at Wegner tell me they tolerate no more than .001" runout of the crank snout.

jp
dhardison
11-26-2006, 10:06 AM
Dan, are you sure it's the balancer? With my ATI I don't see any runout. No, not really. I initially thought my factory balancer was the problem, but my Fluidampr also has what I would call severe runout. I hope it's not the crank....
dhardison
11-26-2006, 10:07 AM
Dan,
Is the runout from the crank end? Or is the balancer not "square" to the crank?

The boys at Wegner tell me they tolerate no more than .001" runout of the crank snout.

jpFrom the lateral measurements I've taken I'd say 1) the balancer isn't square with the crank or 2) the end of the crank is 'bent' a little. I need to measure runout on the crank end itself I guess.