Plug issue
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Joined: Jul 2022
Posts: 89
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From: Scotts Valley, CA
Plug issue
I've only put roughly 1,800 miles on the Vette since I bought it, but figured a plug inspection might be a good idea. Seven of 'em looked pretty much perfect. The eighth looked like the pics. What causes this?
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
In the first pic, it appears the insulator is chipped off. I assume you don't know how old these are.
Do they all match as far as make and part number? I'd install a new set and run it for several hundred miles and recheck them.
Do they all match as far as make and part number? I'd install a new set and run it for several hundred miles and recheck them.
Burning Brakes
Joined: Apr 2020
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From: Western NY
I would put new plugs in it and reevaluate as previous post suggests. also what cylinder did that come from? is it a cylinder that has the vac modulator hooked to it - if you have one - or anything else hooked to it that could introduce any fluids to it?
Pat
Pat
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Joined: Jul 2022
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From: Scotts Valley, CA
Argh. Not the answer I was looking for, but was kind of expecting.
They all match - Accel 376. Engine (and plugs) only has ~ 6,200 miles on it. The insulator's not chipped... must be an optical delusion. They all cleaned up like new, and they were all gapped to spec as removed, so I reinstalled them.
It was cylinder #7. All vacuum hose routing is stock... I don't believe there's anything unique about that cylinder, but please clue me in if I'm wrong.
For the record, I did not enjoy dealing with the chrome shields over the plugs on the driver's side, especially the front one ; )
For the record, I did not enjoy dealing with the chrome shields over the plugs on the driver's side, especially the front one ; )
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From: Scotts Valley, CA
It didn't look like oil fouling to me, but I didn't have a more logical alternative. The intake manifold bolts - and pretty much every other bolt I've touched on this engine - were snug at best, definitely not tight. If the intake manifold gasket was breeched, however, I'm guessing I'll have to pull the manifold and replace the gaskets? It'd be great if just torquing down the manifold was the fix.
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I'd certainly give that a go first. What do you have to loose? Retorque those intake manifold bolts. And monitor the situation. It's not at all unusual to need to retorque a intake manifold.
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From: Cool Northern Michigan
It would be impossible to find any data or stats on successful Intake Manifold installation, obviously.
But I would wager two-thirds are NOT installed correctly.
People seem reluctant to use a quality sealant, enough sealant and cover the entire gasket properly. (both sides)
Some installers insist that the Printo seal is just as good as RTV. Ah-no.
And I believe it's the only gasket on the entire engine that has to seal gas, oil, air & coolant.
It is imperative to have a 100% seal across the entire gasket or issues will crop up eventually.
But I would wager two-thirds are NOT installed correctly.
People seem reluctant to use a quality sealant, enough sealant and cover the entire gasket properly. (both sides)
Some installers insist that the Printo seal is just as good as RTV. Ah-no.
And I believe it's the only gasket on the entire engine that has to seal gas, oil, air & coolant.
It is imperative to have a 100% seal across the entire gasket or issues will crop up eventually.