Backfiring after new plugs installed

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ChuckN

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Hello,

I'm a new member, but the first repair I have done to her(still need to name her), was changing the spark plugs. I got the old ones out and she needed new plugs so bad(see attachment below). Put in some double iridium plugs from Bosch. And after I relubed the plugs with the silicone jelly and plugged everything back in, only one side of the head is backfiring in the muffler. Still need to find out if im running just slightly lean to have this happen, or if some wiring needs to be replaced. I did notice one of the plugs was drenched in fuel when I removed it. Maybe 1 cylinder isn't sparking off... anyways if y'all have any experience with this, I would love to learn! Google gives bad advice!
Been there, done that. Had a helluva time with a backfire on a SBC. Swore I checked firing order, and yet….I was wrong. Glad you got it sorted!
 

Dryriver1

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Silicone jelly is really called Dielectric Grease, it’s purpose is to Protect electrical connections and wiring from salt, dirt and corrosion. It helps extend the life of bulb sockets. It Prevents voltage leakage around any electrical connection, it can also prevents spark plugs from fusing to boots.
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Also known as silicone grease.

You can use it on o-rings, rubber hoses, etc., anything rubber.
It keeps the rubber "alive" or from breaking down due to heat, chemicals, and such.
 

Dryriver1

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"Try Vaseline as a sub for dielectric grease. It'll melt real fast though some remains."

RustyNails, fwiw... I used to work in the h.v electrical utility field and oilfield equipment support yards.

It is not recommended to use Vaseline or any other petroleum based products on any natural rubber gaskets, o-rings, insulating materials, etc. As the petroleum base tends to break the soft rubbers down.

That as as per manufacturers. One thing I don't understand and I always questioned was, well we use rubber hoses for fuel, some diaphragms on pressure switches and valves that carry oil, diesel, gas, kerosene, etc. are made of rubber then what about that?
I could not understand it, but something is better than nothing to keep the rubber insulators from sticking on the plugs.
 

squaredeal91

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I use Vaseline for my battery terminals on the regular
 

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