Here is the out of round wear I was talking about. Obviously from an oblique angle as an ortho perspective is impossible on this subject without stage lights and a bunch of other crap.

The distance between the arrows is the intended chamfer angle which is consistent about the entire radius except in the section of uneven wear you can see the wear pattern or trough ate away enough material to fully erode the chamfer in that one section...Right after that its back to normal...The worst section is inline with the roll pin on the left side

 

so did you get a new dizzy put in? was there ever a true root cause determined?

 

not yet...I should contact them and see what the hold up is

 

Looking at the teeth on that gear in the picture, it appears that the ower left in the picture show abnormal wear on the top of the tooth. The teeth on the upper right of the picture show a sharp edge. It is hard to tell from a pic, but if this is the case, along with the machined area between the arrows, my bet is that the gear was drilled off true. It would then change tooth clearance as it rotated and cause the shaft to wobble. At some point the clearance becomes so tight that something has to break. In your case it was the roll pin and not a tooth. Make sure you got all the pieces out of the crank case. If yu are going to use that distributor, check for scoring in the bearings in the distributor housing. Probably want to replace the whole thing.
I had an E type V12 jag that had wonderful English machining in the gear box. They drilled it so the lay shaft did not run parallel to the input/output shaft. This caused the gears at one end to be to close in engagement and finally cause the destruction of one of the gears in the lay shaft at 28000 miles. The lay shaft was $1200 and a new gear box was over $3500 back in '75, when a cars were about this much.

 

They said they would replace the whole unit...I finally got my call tag for it today they should have it monday.

They tried to send the call tag much sooner but it never showed up in my email...I finally bothered them about it and they got one to me today...

Hopefully the turn around time isnt too long.

 

I got the distributor back it was brand new unit in a retail box with a steel gear pressed on it.

Unfortunately there appears to be an issue with the end of the distributor shaft. The section of the shaft that engages the oil pump drive appears to be out of tolerance it is either bent or has been distorted or mushroomed such that it will not fit into the bore hole where the end of the oil pump driveshaft resides.

As you attempt to install the dizzy it slide down about 1/4" past the first machined collar on the distributor body then stops with a clank about 1+" from being properly seated. If you press down and rotate the rotor you can feel resistance as that shaft binds up in the bore hole.

Maybe it just needs to be clearanced but its been sent back for them to inspect the shaft. Im not in a rush to destroy any cams