VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Play in Distributor gear

While I have my distributor out to put in the missing thrust washer, I now notice the gear on the distributor shaft has a bit of rotational play. Appears pin may have worn a bit (or pin holes), moves about 1/16" of rotation. Should this be a tight fit (no noticeable play) or is some play normal(car is only 82 years old!). If there should be no play, has anyone replaced the pin successfully, is it a big challenge, or found another method to remove play (like a spot of weld in holes)? The distributor otherwise looks very good, teeth in gear good etc. My primary concern is shearing off the pin if there is too much play as well as challenge of getting timing perfect. I also suspect it will contribute to a small amount of end play as it permits shaft to move up while gear stays put in relation to camshaft.

The gear should be tight on the shaft and have no movement.

A/M, have you seen the pins replaced? I assume a machine shop would overbore slightly and custom make an O/S pin and press in place. Sounds like a ticklish job, may ask around if anyone has a decent one for sale or trade.

I installed a new gear and a roll pin to cure the problem on one engine.

I have found that the pins are most often partially sheared. Removing the pin and then installing a replacement pin is all that is necessary to tighten the gear on shaft. I have used a common nail for the pin on most occasions as they are soft enough to shear if the distributor shaft jams. Yes you can use a harder pin but will loose the safety of the shear pin. Or you can use red loctite (most often not necessary) to secure the gear on the shaft.

Chipper, were the pins only a snug fit originally and peaned on the ends to secure (mine were obviously peaned on ends with a press of some sort leaving a checkered pattern on both end of pin and on gear flange). Peaning I assume will also assist in tightening the fit. I will try your suggestion, figure the old pin should drive out easily as it has play now.

Yes the original pins were pressed and have the crosshatch pattern. The old pins can be a bit tricky to get out as the partial searing causes a ledge to form which can inhibit pushing it out. If you rotate the gear on the shaft all the way against the rotation (counterclockwise looking from the gear end) that will make it easier to push out the pin.

I know that people replace the soft pin with a roll pin. They are hardened and too tough. The originals were intended to shear before breaking the distributor or cam gear. Not so with the roll pins or other harder pins. Just a word to the wise.

What would break the pin that wasn't already a major problem?

Took the Dist, to local engine shop and they put a new "split pin" in. The old pin was badly worn. Reinstalled Dist. in car, no end play at all. Now I can set about doing the timing steps as per Bill's excellent guidance on '31 Chevy Site.

The distributor gear or camshaft gear or even the camshaft if the shaft in the distributor sticks even for a brief moment. If the soft pin shears only have to free up the shaft, remove the part that jammed the distributor and the pin.

The pin in my '31 sheared because I forgot to turn the grease cup and it froze and sheared off. Had a heck of a time getting the broken pin out and as per Chipper I used a cut off nail as a replacement. No problem so far after a 100 miles or so. I do turn the grease cup every so often now.