What does a clicking GM distributor mean?

[Deuce Rails]

I apologize in advance for a basic question, but the only distributor I'm really familiar with is the diver's helmet one on my flathead.

I'm the caretaker of my wife's grandmother's '68 Buick LeSabre 400. It has a Buick 350 engine, and the original distributor, including a good old generator.

The distributor is making a clicking noise, and seems to makes a louder click on one cylinder fire than the others. How much clicking noise is normal, and what would one cylinder louder than the others mean?

Does anyone have a link to GM distributors 101 that shows how to check point gaps and such stuff? What else should I look for?

Thanks in advance,

Matt

[Deyomatic]

Have you looked under the cap yet? I guess it could be any of the moving parts in there. The cam might need some dielectric grease, then again the bearings could be shot. The rotor might be rubbing on something.

[DrJ]

You sure it's not lifter noise at the cylinder next to the distributor?
Could be the cap not fastened down tight too.

[Jimv]

i would check the cap also.
68 buick had a alternator.
JimV

[Petejoe]

Cracked or loose cap, broken rotor, points may have moved on it mounting postion some. Gm distributors are easy, Just get yourself some replacement tuneup items and throw them in.
The only tricky part is adjusting the point gap when the distributor shaft lobe opens it Here's some basics.
great site (http://www.partsplus.com/shared/Marketing/EngineTuneUp.pdf)
distributors (http://www.mgcars.org.uk/MG_Elec-Tech/distributor.html)

[OldCarPilot]

Just so you know the dizzy on a GM shouldn't make any noise if its working right. If you are ok with taking it out completely you might check the gear at the bottom. It doesn't happen often, but they do break.
I can't really think of what would make a clicking noise other than something is in there, or a screw in there came loose and now as the dizzy spins its hitting that thing. Either way you look at it its not a noise that it should be making so something is broken and it needs to be taken apart.

[Bruce Lancaster]

The GM window distributor can be set without actually using a feeler gauge--it's been a long time since I had cause to perform this ritual, but I think this is about right:
Install points, just verifying that they do indeed open and close. Start engine, and slowly close the point gap (flex tools are available if hard to reach window) until you have severe misfire with engine about to stall. Proper setting is 1/2 turn of screw other way--most mechanics actually go out one whole turn, back in 1/2 so final adjust is in tighteneing direction against the little spring. This is ancient hot rod tradition here; I hope I remembered the details right.
This is also the only distributor on which it is easy to set dwell, if you have a dwell gauge, as it can be dialed in with engine running.
By the way, on the diver's helmet (to get back to a ral distributor), did you want the Zephyr dual coil instructions? I just realized I have them here to copy, and I suspect that was for you. Bruce

[Deuce Rails]

Thanks, everybody. In particular, thanks to Petejoe for the links. It's time to peek around under the cap. I sure hope it isn't valvetrain noise near the dizzy...

Bruce-- I would definitely appreciate the Zephyr dual coil instructions. I think we talked about that a pretty long while ago, and I bet that you did set them aside for me. Thank you, sir.

--Matt