Very WEIRD spark plug problem (SOLVED?)

Bubba1235

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A friend gave me a holler and wanted me to look at his engine as it was running horrible.

Fired it off on muffs and the thing sounded like it was missing on 4 of the eight cyls.

Pulled the spark plugs and,,, the elelectrodes were gapped like half an inch. They were litterally bent up and away from the center. Other than that they looked fine. Now I KNOW that was not how they were installed (I installed them this past spring) and he swears no one has touched them.

What the heck can cause this? I mean I have seen them bent closer, I have seen them melted off, but never anything like this.
 
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Dirty Dawg

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

Could it be that they started to melt and sag and then cooled of in that position? Ike
 

Don S

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

What engine, what plugs????
Sure it wasn't long reach plugs stuck in an engine that should have short ones?
 

chiefalen

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

Saw that in a prop plane once freekin long, long time ago.

Melted and cooled in weird shapes.
 

APPALOOSA2

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

I agree with Don sounds like wrong plugs for that engine.
 

Don S

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

Not all "Chevy 350s" use that long reach plug. What year is the engine? Are you sure it has heads for the long reach plugs?
 

starsnstripers

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

:eek: That is weird, I also would think they got hot and sagged and cooled that way. How many were spread? Did you keep track of which cyl. or were they on one bank? I guess i'd put a new set in and run it and watch the temp closely. Could be a timing issue, fuel mixture (lean/rich) , or head gasket maybe. Good luck. This is if they are the proper plug. Let us know, (curious?)
 

chiefalen

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

You installed the plugs i gota believe you timed it right all was good.

Hmmm Freekin plugs extended to far into the cylinders is all i can think.

Try installing the shorter plugs, bet they ain't the same heads that came outta the factory on that motor. If correct heads?

He didn't notice nothing amiss all season?

No pinging no nothing? No overheating?

Compression is good, no water in the cylinders, valves good nothing?

A little water will mess up the plugs cause of the explosive force of the gas and water mixed. Increases detonation.

Both sides were messed up or just one side?

If one side i would be thinking leaking manifold or riser, enough to get a little water in the cylinders.
 

Don S

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

Did you check to see if it was getting proper advance?
 

Robj

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

If it got that hot that it melted the ground electrode, I can't help but think there is a more serious problem causing it. It was one bank, could it be a lean condition? Possible manifold leak? I assume the other bank of plugs are OK and they are the same type plug. I would be a little concerned because whatever is causing your plugs to melt, is probably doing more damage to your engine. My guess is a bad manifold gasket causing a lean condition. I think you need to do more diagnosis and fix the problem because if not you may be fixing/replacing the engine.

Have a great day,

Rob.
 

KJSmitty

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

One more time, there was nothing melted or even discolored due to heat. Imagine you have a brand new spark plug. Now gap it to say half an inch. That is what the plugs looked like.

I wonder if the four plugs effected were indexed as in with the ground electrode pointing up, thus they did just get extremely hot and fold backward? The other 4 were already pointing in a down direction thus were not effected by the extreme heat?

Obviously not a reason for doing so yet possibly an explanation of why all 8 did not look the same..

I've never seen nor heard of such a thing however.. As in your title,,,, "very WEIRD"..

:confused:
 

chiefalen

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Re: Very WEIRD spark plug problem

Re: Very WEIRD spark plug problem

Bubba they looked like brand new?

What i mean like you just took them outta the box?

Or like they are supposed to look after 50 hours of hard use? But gapped 1/2 inch.
 
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