Shimming Distributor Shaft

[Bob B.]

Hi all,

I want to add a 0.030 shim to reduce the up & down play in my distributor shaft. Does anyone know how to get the gear off in order to do this? Mine is a 1960, but this should apply to most 50s-early 70s or so distributors.

Thanks,

Bob

[Dick W.]

Re: Shimming Distributor Shaft

Look on the gear. You will see a small hole just below the teeth. There is a drive/roll pin that has to be driven out to remove the gear. To reinstall align the hole in the shaft and gear and install a new pin.

[Joe C.]

Re: Shimming Distributor Shaft

Hi all,

I want to add a 0.030 shim to reduce the up & down play in my distributor shaft. Does anyone know how to get the gear off in order to do this? Mine is a 1960, but this should apply to most 50s-early 70s or so distributors.

Thanks,

Bob

Additionally, note that the distributor driven gear has a small "dimple" mark on it, and it is oriented in the same direction as the rotor electrode. Be sure to re-install it the same way.

Joe

[Stuart F.]

Re: Shimming Distributor Shaft

Bob;

I saw this posting first before going to the private message board. First, you have to drive out the pin that secures the gear to the shaft. Some early model distributors use a tappered solid pin which may be peened over on one or both ends. If it is peened, you may have to grind the material off down to the gear (carefully). Then you must gauge the pin to determine which is the smaller end, and then use a drift of equal or smaller size to drive the pin out. Now, if you are fortunate to have a gear secured with a roll pin, the job is a lot easier. I don't know which years had which (may be someone else can clarify this). With the roll pin, you have to find a drift that is big enough to just engage the material of the pin and not the gear, yet not too small so that it slides inside the pin.

Now, most people and instructions may tell you to have a replacement (new) pin available to reassemble, however, I have reused roll pins myself, and I once reused a tappered pin, but I wouldn't recommend it.

Also, carefully note whether the gear has a dimple on it or not. If it does, that dimple should align approximately with the contact on the rotor. You may want to slip the rotor in place temporarily to confirm this.

Add your shim(s) and gauge you clearance at the pickup. A further note here, I have always had to shim the magnetic ring down from the rotor with the washers they provide in order to establish the proper clearance to the pickup. Remember to rotate the shaft to check the clearance for the + and - tolerance as they all wobble a little.

Good Luck. If you do it right, you'll find it a worthwhile investment as it will save you a lot on spark plug changes, and you can have that baby singing up to red line every time out!

Stu Fox

[Bob B.]

Where to get pin?

Thanks guys!

My pin was secured by some sort of press that gave the ends a waffle pattern. I can drive that out, but where do I get a pin to replace it with?

Thanks,

Bob

[Jack H.]

Re: Where to get pin?

Roll pins are available in various diameters + lengths at most hardware stores...

[Stuart F.]

Re: Shimming Distributor Shaft

Bob;

That "waffle" pattern indicates that it is a tappered pin and you will have to grind it off as I previously noted. As for a replacement, I'm certain that the roll pin is the way to go. After all, I can't imagine the hole in the gear or shaft was tappered as well, Ha!

Like Jack said, roll pins can be found at most hardware stores and no doubt at auto parts stores as well. I don't have the size specs handy, but take your gear along with you to judge diameter and length.

Be careful grinding the "Waffle" material off so you don't damage the gear too much. It would only be cosmetic, but you want the new roll pin to fit well within the gear (flush with outside diameter).

Stu Fox