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Read my spark plug

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Old Jul 20, 2021 | 09:15 PM
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St. Jude Donor '14
Default Read my spark plug

I only pulled #1 and took a pic. It has roughly 1,000 miles on it.

Whad'ya think?


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Old Jul 21, 2021 | 12:57 AM
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Plug looks fine. But the threads would indicate that you probably have a valve cover gasket leaking oil down on the plug...
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Old Jul 21, 2021 | 01:41 AM
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Originally Posted by 7T1vette
Plug looks fine. But the threads would indicate that you probably have a valve cover gasket leaking oil down on the plug...
Yes! But not anymore. I got rid of the parts store chrome valve covers and installed original style orange stamped steel covers with cork gaskets. Much better now.
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Old Jul 21, 2021 | 11:45 AM
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That tan line on the strap makes the turn nicley and appears to be near the base which is good. How does it look down inside around the electrode insulation
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Old Jul 21, 2021 | 01:16 PM
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Too cold, need a hotter plug imo
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Old Jul 21, 2021 | 01:40 PM
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Your profile says you have a 75 L48.
If that is correct and unmodified, the correct plug is a 45 heat range not the 44 in the picture.
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Old Jul 21, 2021 | 01:50 PM
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Originally Posted by 7T1vette
Plug looks fine. But the threads would indicate that you probably have a valve cover gasket leaking oil down on the plug...

plug looks normal.
Clean spark plug hole, anti-seize the treads, check for leaks.

The oil burning telltale would've been in the 'socket' area of the plug....there's no carbon in there....this would not have been burnt off by the plug firing nor the explosions, it's in the cooler condensing valley of the electrode.

All ist Gut!

Unkahal
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Old Jul 21, 2021 | 03:35 PM
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Old Jul 21, 2021 | 04:27 PM
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Originally Posted by L-46man
plug looks normal.
Clean spark plug hole, anti-seize the treads, check for leaks.

The oil burning telltale would've been in the 'socket' area of the plug....there's no carbon in there....this would not have been burnt off by the plug firing nor the explosions, it's in the cooler condensing valley of the electrode.

All ist Gut!

Unkahal
Awesome. Thanks.

How to clean the threads w/o dropping crud into the cylinder? Use a tap?
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Old Jul 21, 2021 | 04:28 PM
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Came across this from Steve Morris Engines. Interesting and good, in-depth explanation.

Last edited by barkingrats; Jul 21, 2021 at 04:30 PM.
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Old Jul 21, 2021 | 04:29 PM
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Originally Posted by MelWff
Your profile says you have a 75 L48.
If that is correct and unmodified, the correct plug is a 45 heat range not the 44 in the picture.
Okay, thanks.

You are the third person to indicate using a hotter plug. One friend of mine and someone in a pm. were the others.
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Old Jul 21, 2021 | 04:31 PM
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Originally Posted by Rescue Rogers
That tan line on the strap makes the turn nicley and appears to be near the base which is good. How does it look down inside around the electrode insulation
Hmmm, I'll try to get out there for another pic.
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Old Jul 21, 2021 | 04:58 PM
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Originally Posted by 7t5
Awesome. Thanks.

How to clean the threads w/o dropping crud into the cylinder? Use a tap?
If it was me....
Screw in clean plug about 3 turns.
Blow out spark plug hole with high pressure compressed air.
Remove plug
Clean with lacquer thinner on clean rag buy twisting the rag and dragging junk out of the hole.
I use nickel anti-sneeze in the plug holes.

BTW, one big mistake I have seen is OVER 'sneezing' the plug threads....reminding you that some of the threads protrude into the combustion chamber....anti- sneeze is conductive...I've seen guys 'kill' the sparkplug by over sneezing.

best of luck....go slow.

Unkahal
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