First question: What exactly is the "pick-up coil", and what does it do?

Second: Are there distributor rebuild kits for the L98 OE dizzy?

 

OK, answered the first question.

...my second question changes a little. Do I ONLY need to change the PU coil, or is there more to it? I've taken the distributor out a few times but never really messed with it much. Cap, rotor, ignition module, PU coil...anything else?

 

Rebuilt distributor would include a new bushing, probably new drive gear, maybe new shaft if needed, etc...


To replace the PU coil, pull the dizzy, knock the rollpin out of the gear, and slide the shaft up out the top.

FWIW, unless oil is seeping up in the top of the dizzy, or the shaft is bent/has play side to side in the bushing, I see no reason to "rebuild" a distributor.

 

I might add, cap/rotor would be tuneup, ICM if needed, PU coil if needed, reluctor if cracked/broken.

 

I'm not tuning up as much as I'm trouble shooting. I'm going to be replacing my wells ICM with a ACdelco, and replacing the PU coil.

The dizzy is physically fine, it's the electronics that I'm concerned about.

 

I just rebuilt mine with a new AC PU coil and AC ignition module. Also upgraded cap and rotor as well.

 

If you'v never done it before you might want to just buy a rebuilt unit from the parts store.

Main problem.... getting that distributor shaft out! People act like it just slides right out the top as soon as you get the gear off the bottom. T'aint so! Oil schmutz builds up on the shaft and it will not slide through the upper bushing. You either spend a long time twisting and turning with plenty of penetrating oil or you get impatient and bang it through with a hammer, usually popping the upper bushing right out of the top of the distributor. Then you go to put it back in and find it doesn't go in perfectly straight (unless you know the "trick) and the distributor shaft binds up when you put it back together. Oh yes, the fun of tearing into your first distributor! I get misty just thinking about it.

 

Couple of tips on distributors: to help get the shaft out use a carb cleaner such as GumOut. This cuts through the build up of varnish in no time.

If you want to shim for less end play the minimum end play is 12 - 15 thou (.012 - .015"). Don't go tighter as the housing expands more then the shaft as it heats up.

When the drive gear is placed back onto the shaft the dimple goes in line with the rotor (slot on top of shaft). And the gear end is toward the housing.

Check the 'star wheel' at the top of the shaft. Make sure that it is still tight on the shaft and unable to be moved. Check the magnets for cracking, swelling, and splitting. If in bad shape a new shaft can be purchased from GM.

RBob.