Oil on Spark Plugs

Ispool · 06-26-2014, 11:02 PM

I was helping a buddy with an n54 change his spark plugs today and 3-4 of the plugs were pretty drenched in oil...the entire bottom part, pretty much. Is this normal? The coil packs were all clean and dry.

924er · 06-26-2014, 11:09 PM

could be his valve cover gasket.

007_e350 · 06-26-2014, 11:11 PM

It the head gasket ... valvecover gasket will have oil ontop plugs not inside threads

924er · 06-26-2014, 11:53 PM

Quote:

Originally Posted by 007_e350

It the head gasket ... valvecover gasket will have oil ontop plugs not inside threads

yeah?

Ingeniator · 06-27-2014, 12:39 AM

Quote:

Originally Posted by 007_e350

It the head gasket ... valvecover gasket will have oil ontop plugs not inside threads

Quote:

Originally Posted by 924er

could be his valve cover gasket.

It is highly unlikely to be the head gasket. If you want to be sure run a compression/leak down test. As for the oil on the plugs 99% of the time it is the valve cover gasket and it is leaking into the cylinder via the spark plug threads.

007_e350 · 06-27-2014, 07:50 AM

Quote:

Originally Posted by Ingeniator

It is highly unlikely to be the head gasket. If you want to be sure run a compression/leak down test. As for the oil on the plugs 99% of the time it is the valve cover gasket and it is leaking into the cylinder via the spark plug threads.

If this is true the spark plugs arent sealing the cylinder ?? I had my coil filled with oil but when I pulled the spark plug it was dry

135Pats · 06-27-2014, 08:06 AM

GENERALLY SPEAKING

Oil on threads but not business end = VCG

Oil on the electrodes = compression test time.

Many gaskets leak on these cars...head gaskets are rarely among that group. But it does happen. OP make sure it's not soot from a rich burn, it can look like oil in that it's just this black nasty stuff. But it'll have a far more ashy and sooty feel to it, oil won't.

dannygee90 · 06-27-2014, 08:38 AM

How many miles on car?

Most likely Valve Cover Gasket

Rat_House · 06-27-2014, 09:51 AM

Is the oil dirty or is it clean? if its clean then it may have just been spilled during the last oil change.

shadow191 · 06-27-2014, 10:48 AM

If the coil packs are dry, it can't be a spill.

Quote:

Originally Posted by Rat_House

Is the oil dirty or is it clean? if its clean then it may have just been spilled during the last oil change.

Ingeniator · 06-27-2014, 11:41 AM

Quote:

Originally Posted by 007_e350

If this is true the spark plugs arent sealing the cylinder ?? I had my coil filled with oil but when I pulled the spark plug it was dry

Quote:

Originally Posted by 135Pats

GENERALLY SPEAKING

Oil on threads but not business end = VCG

Oil on the electrodes = compression test time.

Many gaskets leak on these cars...head gaskets are rarely among that group. But it does happen. OP make sure it's not soot from a rich burn, it can look like oil in that it's just this black nasty stuff. But it'll have a far more ashy and sooty feel to it, oil won't.

If your valve cover is leaking as you remove the plug you contaminate the threads with oil. Like Pats said if the electrodes are oily not sooty then you need to run a compression test and then a leakdown to determine if it is valve seals or rings etc.

Ispool · 06-27-2014, 05:40 PM

Quote:

Originally Posted by Rat_House

Is the oil dirty or is it clean? if its clean then it may have just been spilled during the last oil change.

Around 40k miles on the car I think. Oil was clean and looked good...not burned or ashy. His oil was actually changed last wk at the dealer and apparently an oil filter housing gasket was replaced due to leak.

I'll tell him to check the valve cover gasket. Thanks for the advice!!!

06-26-2014, 11:02 PM	#1
Ispool Thanks God for ball bearing turbos... 4 Rep 44 Posts Drives: 09 E92 Join Date: Sep 2013 Location: TX iTrader: (3)	Oil on Spark Plugs I was helping a buddy with an n54 change his spark plugs today and 3-4 of the plugs were pretty drenched in oil...the entire bottom part, pretty much. Is this normal? The coil packs were all clean and dry. __________________ JB4 G5 ISO, BMS DCI, BMS cowl filters, PSS, AP DP, TCU Flash future mods (PM me if you're selling): focal components, quaife/wavetrac LSD, M3 control arms/guide rods/rear upper link arms, M3 front sway bars, Ohlins R&T.
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06-26-2014, 11:09 PM	#2
924er Colonel 349 Rep 2,049 Posts Drives: e92 335i '10 Join Date: Feb 2014 Location: Socal iTrader: (0)	could be his valve cover gasket.
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06-26-2014, 11:11 PM	#3
007_e350 Lieutenant Colonel 222 Rep 1,909 Posts Drives: 335i 2008 MHD'd / x5d E70 Join Date: May 2013 Location: left lane iTrader: (3)	It the head gasket ... valvecover gasket will have oil ontop plugs not inside threads
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06-27-2014, 08:06 AM	#7
135Pats Major General 456 Rep 6,478 Posts Drives: A few BMWs Join Date: May 2012 Location: Maryland iTrader: (3)	GENERALLY SPEAKING Oil on threads but not business end = VCG Oil on the electrodes = compression test time. Many gaskets leak on these cars...head gaskets are rarely among that group. But it does happen. OP make sure it's not soot from a rich burn, it can look like oil in that it's just this black nasty stuff. But it'll have a far more ashy and sooty feel to it, oil won't. __________________ E88 N54 Alpinweiss/Coral Red/Motiv HTA 3586r Tial .82AR/Other stuff...652WHP F30 N55 XDrive EBII
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06-27-2014, 08:38 AM	#8
dannygee90 First Lieutenant 33 Rep 386 Posts Drives: f86 x6m Join Date: Jul 2011 Location: United States iTrader: (1) Garage List 19 x6m [0.00]	How many miles on car? Most likely Valve Cover Gasket
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06-27-2014, 09:51 AM	#9
Rat_House First Lieutenant 227 Rep 372 Posts Drives: M2 Comp, Gated R8, DatsunZ, mk Join Date: May 2013 Location: Stamford, CT iTrader: (2)	Is the oil dirty or is it clean? if its clean then it may have just been spilled during the last oil change.
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