harmonic balancer ID

[ENTDOC]

My balancer took a dump today on the GT40 302. Can anyone ID this as a 50 or 28oz balancer. The numbers on it make no sense.

[ENTDOC]

[vector1]

that's a biiiig imbalance, i'd guess 50. i've a 28 and it looks about half that.

[PANAVIA]

Looks like a 50 to me as well. are there any part numbers on it >? The thing that bothers me the most is that it looks strangely stock to be on a 427R....

[PANAVIA]

post the part numbers , maybe i can look it up with the Balancer MFs.

[PANAVIA]

Ok, check this out: http://www.dormanproducts.com/images...p1/2621001.jpg
keep in mind that this a photo probably of a 28 oz 1970 part.

1995 F150 5.8L is listed as Dorman #DORMAN Part # 594011 More Info {OE Solutions Solid; Externally Balanced Diameter 6-3/8" Width 4-1/8" Weight (lbs.) 7.25 Hollander # 309-326 Ford OE# E8TZ 6316-B #E8TZ6316B} or -- ATP Part # 102017 for {Harmonic Balancer #E8TZ6316B}
Windsor 351 Engine

[Rick Parker]

Yes Chuck it is a 50 oz imbalance. I think all the 28 oz were 3 bolt, and the 28oz do not have that large or design of a void.
If I had to speculate as to why it broke, I would say that the key was not installed properly into the machined area in the crank. Therefore with one end of the key to high and not centered in the machined relief of the crank when the balancer is pulled or pressed on, with the key standing too proud the cast iron of the balancer unknowingly cracks.
often times aftermarket cranks have the snout machined a few (.0005-.002) oversize which requires the balancer to either be honed or the snout massaged to get the right fit.
This assumes the correct key is being used.