Hi everybody,
Okay, seems that the rotor is trying to spin itself upwards into the cap. It's done it twice this past week on two different sets of cap's and rotors. I'm thinking maybe the bearings in the distributor are going out and causing the shaft to buzz hard enough to where the rotor can't hold on. Getting annoying because you can suddengly hear this loud vibrating when it does it. That and the car starts running rough.

I just wanted some second opinions on if anyone else has had this problem before. Thinking of just replacing the dist. It's never been rebuilt and the car has a little over 140k on it.

I'm also thinking of just finding a reman'ed dist since I don't feel like/ and have the time to rebuild one myself.

Things I have replaced/done to the ignition system. Replaced coil is MSD GM-HEI coil, MSD 6AL box, MSD 8.5mm self cut cables (and ohm meter checked as well), rotor/ cap obviousally. I havn't replaced the module... but if the dist is going to be replaced, then the module will be on the reman'ed.

Thanks,
-Dan

 

Go for it... sounds like your endplay is WAY out of whack!

 

I agree, that rotor shouldn't be coming off the shaft, they usually fit pretty damned snug. It doesn't really take long to rebuild a distributor. The longest part is putting the thing back in, and then timing the car again. Have you considered pulling a dist from a junkyard car? Then you could rebuild that one and still be able to drive. Plus, you could find out the endplay right in the junkyard, and if it sucks, you just leave the dist there!

Oh and don't forget the $12 pickup coil either

 

I'm with Tom on this one...reman parts suck, and you may wind up with something worse than you have now. Rebuilding a distributor isn't hard; just do a search for all that TomP and I have posted on it. If downtime is an issue, get a junkyard distributor ($10 around here) and rebuild it ahead of time. Endplay isn't really an issue either...nearly every stock distributor I have ever seen has too much (shoot for around .012), rebuilt or not. Moroso and others possibly make shim kits for Gm distributors for just this purpose, about $5.

 

I just went for a new distributor, but rebuilding it isn't that big of a deal either. I've taken it apart and it isn't that much work. But I have to warn, when you are taking off the snap ring that holds on the pickup coil, be careful not to bust a piece of the distributor off (that's what I did, learn from my mistake). Also, do a search on ignition modules, because I think the consensus is that the Delco module is the best. And if you're really ambitious, you can remote mount the module for better reliability.

 

An added note, fixing the endplay (after doing the dist rebuild) made even more difference than the rebuild itself (which in itself was well worth it)...something to think about!

 

Cool guys thanks. Probably would explain why rarely after driving for awhile I'd get an odd backfire like the engine would want to quit, and then things would be normal again. Only happens on a rare occasion, but probably explains it. Hm, that and the slight miss that has been going on at idle for awhile that I havn't been able to figure out.

_Dan

 

What exactly is distributor endplay?

 

Just wondering what most of you set your base timing to? I was thinking of setting the base timing to 12 degree's over the stock 10 to see if there is a difference in performance. I figure, if it was to ping to just run a slightly higher octane (currently using 87). Anyhow, currently it's set at 10 and seems to run pretty good with the new dist. After taking off the old dist, I noticed that it has been replaced once before. Had a RE-MAN on the back of the old one. The bearings in it were so bad that the thing was really hard to turn in fact. I could also in fact push the shaft side to side a bit whereas the new one seems really solid.

Hm, maybe it explains why I had that occasional miss while driving along. *shrug* Also, anyone have any method's of checking to see if the cam chain is going or stretched without removing the water pump and all that?

_Dan

 

Its the play between the gear and the housing. It should be around .012-.015, but is usually at least twice that, causing spark scatter.

 

When you have the distributor installed in the engine, you can easily check for timing chain wear by grabbing and holding the rotor (cap off distributor) with one hand and turning the engine in the direction of rotation (clockwise as viewed from the front pulley) with a breaker bar and a socket. There whould be some play, but if you move the crankshaft like 3/4" of and inch or more before you feel the rotor start to move you can bet there's a lot of play in the timing chain.

Eric

 

There is a roll pin that holds the gear to the distributor shaft.
There is no play allowed with this retention design.
IF you have that much up down play, go get another distributor, yours is history.
Modules ANY BRAND, it makes no difference. I know, been thru six due to alternator problems (high voltage spikes can ruin a very good automotive overtaking move on the road)!