Distributor Cap Question

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89Suburban

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Every 4 to 6 months I get this white **** on the terminals in my D cap. I kept buying a new one and it does the same thing. So instead of pissing my money away, I just pop it off and use a dremel with a wire wheel and go in there and brush them clean. I have gone through this with other vehicles as well. Anybody else have this problem? The cap sits nice and tight on the base and is dry inside. Real pain in the ass doing this all the time. The attached pic is not my cap, but shows the stuff on the terminals I am talking about. I can't understand why I get so much **** on the terminals in such a short time period. I can tell it's time to clean them because my mileage starts to take a hit and I can hear the way she's firing and idling funny. When I take it off to clean it I will post pics and what my routine is and how I do it.

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RetroC10Sport

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The terminals are aluminum instead of brass. I think better caps have brass terminals.

It's the build up from the two metals rubbing off on each other.

The problem with cleaning them is that you're taking off material so the spark has to jump farther from the rotor so it won't be as hot when it gets to the spark plug.
 

89Suburban

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The terminals are aluminum instead of brass. I think better caps have brass terminals.

It's the build up from the two metals rubbing off on each other.

The problem with cleaning them is that you're taking off material so the spark has to jump farther from the rotor so it won't be as hot when it gets to the spark plug.
I think mine are brass. There has got to be a problem if I am replacing a cap and rotor every 6 months, isn't there? You are talking 40 bucks a fix for the better part, I can't afford that ****. If I am going to go through those things I might as well use the cheap parts, costing around 25 - 30 bucks, but that's still 60 bucks a year.
 

89Suburban

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$40?

Dayum. O'Reilly's has a brass term. dizzy cap for $20.
I meant for cap and rotor for high end. I'll just see if I can get a fukin bulk discount since I can't figure out why this is happening.:roflbow:
 

Swims350

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agred no need to change cap and rotor when there's nothing wrong with the rotor since you already bought it. Ours does that, my old man takes a screwdriver or something and picks it off when he sees it on there.

If they were brass they'd look gold from the start inside and out, if they are alum. then they are silver inside and out.

Even some of the high end duralast caps weve bought had alum. terminals.


Here's an idea not sure if you can do it or not but what about the dielectric grease can you use it on a dist. cap posts inside like that? it's the crap you put on your battery terminals to keep down corrosion.
 

Old77

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To answer your question, yes that's a little too often to have to replace the cap. They should last you several years.
 

89Suburban

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To answer your question, yes that's a little too often to have to replace the cap. They should last you several years.
:emotions122:
 

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X2 on the dielectric grease. You need to put enough on to keep oxygen out of the terminal connection.
 

CoggedBelt75

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Between the high voltage arch and the condensation buildup, this will always be present to some degree. Sounds like the gasses built up inside aren't getting vented out tho. Used to run a dual point Accel back in the day and the cap had a vent on top. Even my MSD has one on the cap. Not up on your factory dizzy but if the cap isn't vented then look on the flat plate on the shaft and see if there are 2 screens along the edge. If there is some, more than likely they are plugged. Also a pea size dab of dielectric grease on the outside terminals will help seal off moisture from seeping thru the boots. And since the cap is off alot, grab a hold of the shaft and see if there is excessive movement in it. If there is, then the bearing has failed. A worn dizzy will wobble creating a bigger gap for the arch. My .3 cents for what it's worth. A short read on this...http://www.tomorrowstechnician.com/Content/Site301/SmartProducts/PATTERNFAILURES_00000000860.pdf
 

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Thanks guyz. I will have to try that. :High 5:
 

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