Oil on my plugs

[1995 525i]

Changed my spark plugs yesterday after Bill B and i found i had one incorrect spark plug in my car. All my plugs have oil on them. Not much but it is noticeable to the eye and touch. Three questions why? is it a major problem and can I fix it myself?

Any ideas?

Thanks,

Michael

[Ross]

Oil on the outside of the plugs means a leaking rocker cover gasket, easy fix.
Oil on the firing end is a different animal. Let me guess, the different plug was the most fouled if this is the case.
Oil on the firing end is usually an indicator of worn engine internals.
The odd plug was probably a replacement for a previously oil fouled one.

[1995 525i]

Oil on the outside of the plugs means a leaking rocker cover gasket, easy fix.
Oil on the firing end is a different animal. Let me guess, the different plug was the most fouled if this is the case.
Oil on the firing end is usually an indicator of worn engine internals.
The odd plug was probably a replacement for a previously oil fouled one.

The oil was on the threads of the plug. Granted there isn't much at all but there was enough to make Bill and I wonder. I plan on replacing my valve cover gasket soon (just got it yesterday) as I know there is a small leak there. Perhaps that is the cuplrit. Thanks for the response.

Michael

[Ross]

Clean it all out with carb cleaner or such and use a little anti-seize on the plug threads.

[billb]

The oil was on the threads of the plug. Granted there isn't much at all but there was enough to make Bill and I wonder. I plan on replacing my valve cover gasket soon (just got it yesterday) as I know there is a small leak there. Perhaps that is the cuplrit. Thanks for the response.

Michael

...as you could be getting some blowby around the rings. The valve cover gasket will heal the drips outside, but won't solve the leaks inside. I'd go with a 3k change interval and move up to something like 15W40 or 20W50 dino oil since you're not running synthetic.

His car doesn't smoke though, so it's pretty weird to have oily plugs...

[632 Regal]

sounds like the valve cover gasket.

[billb]

sounds like the valve cover gasket.
...just what was inside the engine.

[ericbendler]

I had the same problem...oil on my plugs. I am going with a valve cover gasket change. My plugs were loose, and I had oil on the threads of my plugs as well.

[Bill R.]

cross section of the threads on a spark plug and the threads in the hole when they are screwed in, you'll notice that there is a gap on every thread .

When they are torqued this slight clearance or gap on the threads makes a spiral channel that oil in the combstion chamber can wick its way up.

A very small amount of oil is present in the cylinder and combustion chamber when the engine is running, you can have just enough oil coming by the rings and the intake valve guides that it won't show up on the electrode because it will burn off fairly completely but it will wick up the threads on the spark plugs all the way up to the sealing washer on the plugs.

As long as the oil consumption it still relatively normal i wouldn't worry about it at all.






...just what was inside the engine.