Arching on distributor cap
Logistics Pro
Joined: Nov 2013
Posts: 3,930
Likes: 1,201
From: Mojave, Ca
There is an electrical storm of arcing in the distributor cap normally. The spark needs to jump to the post some how. The rotor only makes physical contact with the center post of the distributer. All other post are about 0.030" away from the rotor and the spark jumps to the post via arching.
Your cap looks normal.
Your cap looks normal.
i ain't rite
Joined: Mar 2005
Posts: 65,613
Likes: 5,632
From: Marlboro Mental Hospital.
agreed. cap looks normal, and also looks like a better quality unit with brass contacts instead of the cheaper aluminum contact caps most places sell the past 20 or so years.
Hotshot
Joined: Jul 2020
Posts: 10,582
Likes: 2,678
From: Near Salt Lake City
Looks normal to me
The cap and rotor are scheduled replacement at 60k miles
By then they will show significant wear
The aluminum terminal ones are wat worse for buildup
There is acid created inside the cap when the spark jumps the gap
That acid forms small droplets you can sometimes see, it's no big deal, that is normal too, it is what builds up the white corrosion on the aluminum cap terminals
Your brass ones are better for that, the acid does not affect those brass ones
The cap and rotor are scheduled replacement at 60k miles
By then they will show significant wear
The aluminum terminal ones are wat worse for buildup
There is acid created inside the cap when the spark jumps the gap
That acid forms small droplets you can sometimes see, it's no big deal, that is normal too, it is what builds up the white corrosion on the aluminum cap terminals
Your brass ones are better for that, the acid does not affect those brass ones
Hotshot
Joined: Jun 2015
Posts: 12,893
Likes: 2,449
Ok. As was mentioned the rotor does not touch the wire terminals in the cap. An arc jumps the gap. Good choice on brass instead of aluminum. I always buy caps with brass.
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