Light oil coat on spark plug threads. - 986 Forum - The Community for Porsche Boxster & Cayman Owners

eomak · 08-06-2008, 12:38 PM

Hi, bought 2003 2.7 boxster last year at 52,000km's.I was planning to change the spark-plugs and 8,000km's later i finnaly got around to it.The job was pretty straight forward just took some time.I have no history on when the last time they where changed or if even changed at all since new.The ones i pulled out have Beru Ultra written on the sides from france GR-6KQU.The tips of the spark-plugs look like normal wear dry ,greyish with light brown tint.But on all 6 spark plugs,on the threaded part starting from base where that washer ring thing is to almost the starting point of threads there's a light coat oil /gas on all sparkplugs exactly the same on all them.This normal?I've changed a few spark-plugs on dif. cars dont think i seen this before.Any ways after i put the new ones in ,the engine has a nice intake small high performace whistle sound now as u rev the engine and i think its what it should like and bit more responsive throttle.It was sounding/ running fine with the old in too.Shouldnt spark plugs be dry in that area since it's just the area u srew the plug in?Or is it just that there the org. from new and over time oil/gas just got in the threads? thanks.

Lil bastard · 08-06-2008, 02:17 PM

Sounds to me like the PO oiled the threads, maybe as a substitute for anti-sieze. Could also be as you say oil leaked past the seal up the threads, but I've not seen this on my boxster.

They should be dry. A leaky spark plug tube O ring would cause some oil to leak past the head, but unlikely that all 6 cylinders O rings were leaking at the same time - are the plug tubes all oily inside?

Beru are the OEM plug along with Bosch, so these could be original. If it were me, I'd use a cloth on a tool to try and clean any excess oil from the tap on the head and install the new ones dry.

eomak · 08-06-2008, 07:25 PM

Quote:

Originally Posted by Lil bastard

Sounds to me like the PO oiled the threads, maybe as a substitute for anti-sieze. Could also be as you say oil leaked past the seal up the threads, but I've not seen this on my boxster.

They should be dry. A leaky spark plug tube O ring would cause some oil to leak past the head, but unlikely that all 6 cylinders O rings were leaking at the same time - are the plug tubes all oily inside?

Beru are the OEM plug along with Bosch, so these could be original. If it were me, I'd use a cloth on a tool to try and clean any excess oil from the tap on the head and install the new ones dry.

hi, i was able to look inside the sparkplug entrance and it looked pretty dry and clean but was some oil on the threads.Any reason y the O rings would leak if that and on low milage engine?I guess only the way is to check a sparkplug 2 weeks from now and c if oil on it again.Some thing i should be worried about?
thanks

IowaS · 08-06-2008, 07:55 PM

Lil bastard had very good points here....if you are concerned, take it to a reputable mechanic to "read" the plugs. Reading plugs is an art not a science.....IMO if the car is running well....dont make a problem out of nothing....could be diametric(sp) oil...could be alot of things...

should have said diametric(sp) grease not oil...must have been the 3rd Coors...

Lil bastard · 08-06-2008, 08:34 PM

Quote:

Originally Posted by IowaS

Lil bastard had very good points here....if you are concerned, take it to a reputable mechanic to "read" the plugs. Reading plugs is an art not a science.....IMO if the car is running well....dont make a problem out of nothing....could be diametric(sp) oil...could be alot of things...

should have said diametric(sp) grease not oil...must have been the 3rd Coors...

I think you mean dielectric grease - this is used to insulate ignition parts from moisture such as a distributor cap or spark plug caps, it is a grease which conducts electricity.

Diametric grease sounds like it was invented by L. Ron Hubbard and something Tom Cruise or John Travolta might use...

Lil bastard · 08-06-2008, 08:41 PM

Quote:

Originally Posted by eomak

hi, i was able to look inside the sparkplug entrance and it looked pretty dry and clean but was some oil on the threads.Any reason y the O rings would leak if that and on low milage engine?I guess only the way is to check a sparkplug 2 weeks from now and c if oil on it again.Some thing i should be worried about?
thanks

O rings do leak on the M96 engine and usually call for a replacement of the o rings and sometimes the tubes at some point, but usually not at the mileage you report.

If your tubes appear dry, I would do as you say and install them - dry. Perhaps the originals weren't torqued properly and the seals on the plugs didn't seat properly allowing some oil to migrate up the threads - they s/b torqued to 30+3Nm (22+2Ft. lbs.) first fitting, 25+5Nm (18+3.5Ft. Lbs.) on any subsequent fittings of the same plugs.

IowaS · 08-06-2008, 08:43 PM

Quote:

Originally Posted by Lil bastard

I think you mean dielectric grease - this is used to insulate ignition parts from moisture such as a distributor cap or spark plug caps, it is a grease which conducts electricity.

Diametric grease sounds like it was invented by L. Ron Hubbard and something Tom Cruise or John Travolta might use...

lil bastard...I have never had the opportunity to meet you...but I would like you...good stuff....my vote would be Tom Cruise...