Oily spark plugs

[Jaymzfc]

Hi, the past 2 spark plug changes (2 in 15 months) ive noticed tha a couple of the plugs have oil on the thread side of the spark plugs, the engine runs fine no misfire no smoke, should i be worried??
Any ideas ???

[DSilvaSport]

any pics?

[Jaymzfc]

Just imagine dipping a spark plug in oil, and there you have it. a google search told me valve stem seals or worn piston rings (pls god no). but thought i'd get a proper opinion.

[MattDilley]

Do you have any smoke at all when the engine runs? Cos this would be a good indication of rings, stem seals or head gasket?
A common cause of oil on the plugs is when filling the engine up with oil, the bit that misses the whole goes down into the wholes where the spark plugs sit, so when you remove the plug the thread becomes covered in oil?

[Jaymzfc]

Hi Matt, yeah in fact in a weeks time im going to remove the plug again and see if its full of oil, but make sure before the chamber is clean. there is no smoke no misfire nothing really and the engine runs great.

many thanks

[andreas395]

Had this on both of my Williams change the rocket cover gasket but use some hi temp silicone when fitting it should do the job has with mine anyway

[Wobba]

This is most likely oil falling around the plug as you extract it from an oily spark plug well.

The reason the well is oily is due to either:

a. A compromised camcover gasket (cheap and easy)
b. The cam carriers have been replaced with ones from a different F7* series cylinder head.

Cam carriers are matched to each individual engine and can change shape with the main cylinder head with age. It can be sorted though with proper use of sealant. If not, they can leak into the spark plug wells.