Distributor cap/rotor problem
 

The metal contact in the center of the rotor on my 01 Blazer,4.3, keeps breaking off. Replaced rotor 3 times in the past year and a half. 2 new caps. All screws seems to be properly fastened. Any ideas where to go next? Thanks.

What brand rotor are you using?
You not "gorilla torqueing" the screws are you?

Worn out distributor bushings cause excessive radial runout of the distributor shaft causing the rotor to move back and forth as it rotates. As mentioned, cheap quality, (aftermarket) cap & rotor could also be the problem.

Sorry for the reply delay (interrupted by work). Rotors and caps are "Standardbrands". Local Napa store insisted they were better than OEM (even though mfg in Mexico). Screws were not over tightened. I don't want to go to the Dealer if possible for AC Delco. I can get them from Rockauto online, though. At 270,000 km do you think a new distributor might help? Thanks.

Standard is not known for its quality;) Maybe a little better than Duralast, but not much. Not sure if they have brass terminals, but if they do, brass is a cost cutting measure with caps. Aluminum is a far better conductor of electricity, brass is for looks.


As for replacing parts, it depends what the problem is. If the cap & rotor are at fault, or the distributor bushings. Guaranteed its one or both of them. Pull the cap off and see if you can wiggle the shaft side to side, (not rotationally, or vertical). It's not the most accurate way by any means, but if you feel any movement, in any direction, the bushings are bad and the distributor will need replacement. Skip White has a store online, and on Ebay, with aluminum distributors, (not plastic). ~$50 shipped to your door. It comes with a cap and rotor, but you're better off trashing them and get AC Delco. If you install AC Delco cap & rotor, and the bushings are bad, it will destroy the new cap & rotor.