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Oil leak around spark plug

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Will_Ringrose

Senior Member
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So I thought I only had an Oil blow-by issue, but it also seems I have oil leaking around the spark plug on cylinder number 5. the only way I discovered this was after fixing the blow-by issue. I haven't tried to replace the plug yet. I have never seen this happen before.

Any thoughts or suggestions?
 
Are you certain that it is pushing out from the head and not a leaking valve cover gasket? Is your engine smoking a lot? What does #5 plug look like? Fouled or does it look normal?
 
No oil at all around the valve cover, its all pooling under the #5 spark plug then dripping down the back of the motor. very very little smoke at let off from high RPS or when really getting into it but nothing bad.

I haven't taken the plug out yet, I was going to try and tackle this tomorrow after work.
 
Does the GT6 have pushrod tubes the way the TR2-4 does? They sometimes leak ...
 
I believe the early GT6 head does have separate aluminum pushrod tubes.
 
If all else is clean and dry in the plug area, and you have oil coming out around the base of the plug.....that's oil in the combustion chamber.
Pull the plug, you will find oil on the threads all the way down, AND buildup on the end of the plug, either oily or ash deposits.
If the oil is there, probably no amount of high-voltage add-on gimmicks will fix it, and even if you minimize it, the wear or failure issues allowing the oil into the cylinder will continue to degrade.
Might be something simple like too high a rocker flow, oil filling and going down intake guides, seals, or guide issues, who knows.
But one cylinder.....check all plugs (lay them out in order when you pull them for close inspection and comparison).
 
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