I am finding a white buildup on the contacts inside the distributor cap of my 1979 RX-7. It is greatly affecting engine performance. How can I prevent this buildup from happening?

 

Run bigger spark plug wires..? Really, you CAN'T actually do anything to prevent it except find a replacement cap and rotor that has brass contacts instead of aluminum or steel alloy.

Mario III

 

The white buildup is from the moisture due to the winter weather. You could sand it down, put a little gas in it, dump it out, light it up and put it out quick. This will help, I've done it plenty of times.

 

Thanks for the input. I think I'll try to find the brass contacts first. My rotor is brass, but the cap contacts are definitely not brass. I don't know if I'm adventurous enough to try the gas idea.

 

not sure if I'm totally in love with the idea of pouring gas inside of the dizzy cap and lighting it. I mean I've had a vehicle catch on fire before and now I always have an automotive fire extinguisher in my ride at all times to prevent such an occurence. I think I would try wipping out the thing or even buying a new one before I resorted to arson.

 

build up is going to happen on everyday driving cars

 

The residue he's seeing is the result of the aluminum used in cheap caps. Unfortunately, that's just about all you see these days...I had to eBay source my current brass rotor/cap set after a month of searching....which brings up another point. You should always replace that as a set, not just the rotor or not just the cap...

 

Well, I've done it before and it works. Learned it from an old school mechanic and haven't had a car catch fire yet or caught an arson charge.