Read this plug?

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Copymutt

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Any thoughts on this fouling? Only #6, all others are gas rich. Debris has a tan color.

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squaredeal91

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I'll go with the above^^ how is compression on all? Maybe it's just valve guides.
 

fast 99

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Hard to tell could be rich or oil. Rich conditions are detrimental to engine life. Gas dilutes oil, washes cylinder walls. Check compression wet and dry, if possible, a leak down. Get whatever is causing rich condition fixed.
 

Copymutt

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Haven’t ck’d compression, no smoke, doesn't use oil. #8 has a noisy lifter though. Heads professionally rebuilt +- 1000 miles ago. But, that was probably in 1992.
I replaced all plugs. I’ll keep an eye on them. Swapped out Ebrock 1406 for a 1403 recently due to years of corn gas aging in the bowl & tank. Plugs were same prior to switch.
I’ll get a handle on the way too rich & see what happens.
Much thanks.
 

PrairieDrifter

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Looks like a leaky guide or valve seal. That type of leak seems to build on the ground strap where rings usually foul the whole plug.
 
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sidschev

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put it back in and floor it for 50 miles then check it hahahahahaha bet its clean,,,, red line that sucker for a while.......if she blows then you need a new engine.....
 

Copymutt

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While I won’t be doing that you are probably spot on as being a plow truck “all” it’s run time is below 2000 rpm, never gets a good blow out! That’s what happens when you use a truck like a tractor.
 

Copymutt

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KISS principal.
Previously removed and cleaned DS tank as fuel filter was plugged. Pulled 2nd filter just upstream from fuel pump, also near completely blocked. Retuned the 1403 Edelbrock. Runs decent now.
I have a Holly Projection set up, never installed, exploring the adaptor now.
Concept is since for winter use only this would avoid carb plug up & destruction from ethanol.
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