Ignition rotor corrosion

Daves55Sedan

Daves55Sedan

Well-known member
The tip of my ignition rotor (where it contacts with the underside of the distributor cap towers) collects a substantial amount of corrosion, apparently due to the dissimilar metals. The rotor tip is copper plated, but the distributor towers are aluminum.
After thoroughly cleaning the tip using a fine file and then coating the tip with a thin layer of high dielectric silicone compound, the rotor collects still more corrosion after about two weeks of running it like that. When it does, the car runs lousy.
How can I prevent this corrosion.
 
Is the spring on top of it making good contact with the button in the center of the cap?Also make sure the little ground strap connecting the points to the dist case in intact.
 
Yes the spring does make good contact with the center tower (to coil).
Nobody sells caps with copper towers anymore.
There appears to be no wear at all between tip and towers (although the cap and rotor are both several years old).
What about excessive point gap? Point gap is set using feeler guage only. I do not have a dwellmeter anymore. Could point gap be the cause?
 
Daves55Sedan said:
I do not have a dwellmeter anymore.
Click to expand...
V8 y-block point gap is .014 -.015, dwell is 28 degrees.
Dwell meter, do you want one? Have you looked at - garage sales, craigslist & ebay? I've seen a couple on ebay for under $20 delivered, just in the last few days.
 
Maybe running it with incorrect gap point will cause other problems you dont need. How about a rotor with aluminium tip?
 
I am assuming by your avatar that you have a Y-block. I just checked the online information for Standard Ignition products and the distributor cap they offer for a Y-block does have brass contacts. I used to sell Standard parts ages ago and I have always been pleased with the quality of the parts they offer. You might want to check that out.
 
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sidevalve8ba said:
I am assuming by your avatar that you have a Y-block. I just checked the online information for Standard Ignition products and the distributor cap they offer for a Y-block does have brass contacts. I used to sell Standard parts ages ago and I have always been pleased with the quality of the parts they offer. You might want to check that out.
Click to expand...

Small world! I was a Standard rep back in the '80s in the Houston, TX area.
 
It is indeed a small world. Just recieved a Standard dizzy cap from Rockauto. That little lip where the dizzys securing leafs lock chiped off first time I used it. Can I complaint to you guys?
I'm kiddin of course. The cap is well secured in place eventough.
 
Thanks guys. I do always set the point gap with a .015" feeler guage and yes I know that the optimal dwell angle should be about 27 degrees.
I have two 1970's era Sears brand dwellmeters that I used for 20yrs. They do not work anymore. Electronics shops around here wont touch them and if they did it would probably cost a fortune to replace lots of old condensers. I have been winging it with the feeler gage alone the past 20 yrs.
I will look for Standard Ignition parts at local chain auto parts stores, but if I remember correctly, nobody around here carries Standard anymore.
 
ck with autozone got one with brass terminals a while back. you have to ask for the better quality parts. they sell cheap parts to most people, as they want the best price. you have to ask for the better quality stuff. you might also try napa, or O'Rilleys
 
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