1970 Johnson 40hp 40e 70a looking for what spark plug I need right now I have ngk b6s and What gap I need I seen 0.03 my old plugs ends are black
What causes the spark plug end to be black is it bad gas or wrong mixture I used a mixture bottle or it could be the cheap oil the guy gave me might need some better oil to mix with the gas it smokes a lot to when at high revs in a bucket but wasn’t doing that last year on water
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