Plugs Oil Stained Around Threads In Head???

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
hello guys i have a 1982 chevy c10 with a 350 engine. brodix ik180 heads. with acdelco spark plugs and cylinders 23468 have oil coming out around the spark plugs. the heads have 800 miles on them. i took a compression test and i got 185 on all cylinders give or take 1 psi. the truck runs good plenty of power. no misses or smoking from the tailpipes. no weird noises from the motor. any help is appreciated i worried my new heads have issues because the iron heads that was on my motor did not do this. i also hooked a vaccum gauge to it and got 18.5 inches of mercury which is normal for the cam i have according to comp cams.


clear ideally color pictures of the spark plugs ,in the heads and out after they are removed,
then labled as to source cylinder number,
and some idea of how much oil your talking about and how and why you noticed the oil,
would very useful.
I have to assume, your plugs are not oil fouled as you stated no oil smoke, missing etc.
are you sure your not dealing with a valve cover gasket or valve cover breather related oil leak?
the likely routes for oil to enter the combustion chamber are past the rings,
through the valve guides or through a leaking intake gasket.
but all would generally result in oil smoke from the exhaust,
you state everything runs well and no oil smoke,
so it seems an outside the combustion chamber ,oil source is more likely.
Id sure test, and look for the oil source,
I'd spray the area below the valve cover and around the spark plugs with brake cleaner,
to remove all trace of oil and run the engine ,
look for a valve cover gasket or breather leak as an oil source.
 
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why not call brodix cylinder heads
Phone:
(479) 394-1075

and verify your using the correct style and part number spark plug on those cylinder heads,
PlugSeats.jpg

and yeah, your supposed to use ANTI-SEIZE on spark plug threads used in aluminum cylinder heads
taperseat1.jpg


antiseize2.jpg
aluminum is sign
b4c4f4424b6fcf47f997346415cfcaee-png.83019
ificantly softer and weaker than cast iron, especially when its been repeatedly heat cycled or the spark plug threads were subjected of moisture that can cause corrosion to take place
anti seize paste, in many cases, is generally a mix of powdered aluminum,zinc,graphite and copper, suspended in high temp synthetic or lithium grease or waxes, that forms a effective film barrier to prevent threads corroding and binding, due to oxides forming in the thread gaps, it also tends to allow the threads to engage with less force or torque required, making it much easier for a hobbiest or mechanic to feel the plug bottom out and reduce the dendency to over tighten the plugs

guys get frustrated ,especially on the rear pass side cylinders where access is a P.I.T.A. on most c4 corvettes.
this can lead to guys swapping only some of the plugs rather than all the plugs which obviously can result in less than ideal results on durability and performance or damage to the cylinder heads
anti2.jpg

anti1.jpg
 
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