Distributor Gear Question

[M66Stang]

Guys,
Got one of the Pertronix III plug and play distributors for the new engine. I need to change the cast gear to a steel gear to mate with my billet HR cam. Last night I removed the cast gear from the shaft and found it to slip right off when I took the roll pin out. I thought the gears were supposed to be pressed on?? I measured the ID of both the cast gear and the new steel gear and they both are 0.467 which is what I expected. However, the distributor shaft is measuring about 0.465 which is why the gears slide on and off. This means the roll pin will be taking the load of the oil pump. Do you think this is ok?

Thanks,
Mark

 

[Stroked66]

Short answer.......... NOPE!

Long answer............ dizzy drive gears should be press fit, otherwise there WILL be movement and premature wear of the drive gear, regardless of what it;s made of AND, as you mentioned, too much load on the roll pin.

 

[gotstang]

Short answer.......... NOPE!

Long answer............ dizzy drive gears should be press fit, otherwise there WILL be movement and premature wear of the drive gear, regardless of what it;s made of AND, as you mentioned, too much load on the roll pin.

What he said. Sounds like Chinese-crap-itis to me. 0.002" is a normal class fit, fairly loose, and about a country mile from a what a press fit should be.

 

[Mach1Rider]

Will have to agree with them on this.
Your only fix might be using a oversized soild pin to keep the gear in place.

 

[M66Stang]

I contacted Pertronix and asked them about it and they said the roll pin would "lock" in the gear and all will be fine. I agree with your opinions and sent the distributor back to Summit for a credit. I'll find a Ford distributor to use. Change the gear to steel and install the Pertronix III module in it.
Thanks all.