# Plugs fouling (repeatedly)



## Noangelbuddy (Dec 6, 2017)

New crate engine. Plugs are new and were clean and gapped. After running for 10 minutes this is what they looked like when removed. Black carbon and still wet with gas. Have not fine tuned the new carb lean/rich adjustment. Could that be the cause? 
In interest of full disclosure, engine is supposed to have 91 Octane. I put 5 gal of 87 Octane ( failed to consult engine mfg requirement...Doh!) tried to amend that by following with 10 gal of 93 Octane.
Plugs and gap are what engine builder suggested. Wet gas on plugs after running was not expected.


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## Sick467 (Oct 29, 2019)

Cold be the air/fuel mixture and it could be a high float level too (or combination of both). ALSO, This happened on my recent 400 build and I found the timing to be off (a fair amount). I dialed in the timing and the plugs stopped being wet. They would get so wet that if the engine did not start and stay running, the plugs would foul so bad that they had to set for long while or be removed and cleaned and dried. To be honest, I am sure I fiddled with the air/fuel screws during/after the timing adjustments as I was preparing it for the street.. Do a thorough timing analysis and then work on the air/fuel adjustments.


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## Lemans guy (Oct 14, 2014)

Agree with sick, 9 out of 10 carb problems are timing issues. Get timing set right first then dial in carb. Yes it looks way rich. You want a nice clean burn, but it always takes a bit of effort to get there.


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## Baaad65 (Aug 29, 2019)

What they said, mine are burning nice...base at 20*, 11* vacuum advance, 14* bushing, no detonation...runs like a beast


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## Noangelbuddy (Dec 6, 2017)

Sick467 said:


> Cold be the air/fuel mixture and it could be a high float level too (or combination of both). ALSO, This happened on my recent 400 build and I found the timing to be off (a fair amount). I dialed in the timing and the plugs stopped being wet. They would get so wet that if the engine did not start and stay running, the plugs would foul so bad that they had to set for long while or be removed and cleaned and dried. To be honest, I am sure I fiddled with the air/fuel screws during/after the timing adjustments as I was preparing it for the street.. Do a thorough timing analysis and then work on the air/fuel adjustments.


The float level on the primary was okay, I can see it through the window. Secondary was high so I lowered it. Intentionally dialed down the fuel (arbitrary 1/2 turn) to lean it down. Will recheck timing as you suggested when I fire it up tomorrow. It’s time for a Blue Moon. One of the great things about retirement is the ability to slow down like everyday is Saturday. Appreciate the input.


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## Noangelbuddy (Dec 6, 2017)

Noangelbuddy said:


> The float level on the primary was okay, I can see it through the window. Secondary was high so I lowered it. Intentionally dialed down the fuel (arbitrary 1/2 turn) to lean it down. Will recheck timing as you suggested when I fire it up tomorrow. It’s time for a Blue Moon. One of the great things about retirement is the ability to slow down like everyday is Saturday. Appreciate the input.


Gents,
Went back and checked the timing and you guys were correct. Hate to admit it, but I incorrectly set the initial timing and thought it was correct. I had not used a timing light in over 40 years. In hindsight, I should have watched a YouTube video (or two, or three) for a refresher. Thanks again.
NoAngel


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## pontrc (Mar 18, 2020)

Noangelbuddy said:


> Gents,
> Went back and checked the timing and you guys were correct. Hate to admit it, but I incorrectly set the initial timing and thought it was correct. I had not used a timing light in over 40 years. In hindsight, I should have watched a YouTube video (or two, or three) for a refresher. Thanks again.
> NoAngel


Good job buddy 👍


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