[musa]

Ok, the spark plug hole gasket was brittle and a couple plugs had oil accumulation before removal, but how does oil flow down to the electrodes when the spark plugs are torqued to spec? Or is the oil on the electrodes from somewhere else like the valve seals leaking, so was already in the combustion chamber?

 

[mattmar1]

not seeing oil on the threads above the electrodes, so it looks like the deposits are sourcing internally

 

[musa]

not seeing oil on the threads above the electrodes, so it looks like the deposits are sourcing internally

Thanks. Now that explains the puff of blue/white smoke upon start-up when the car is parked overnight ... valve stem seals, yes? Doesn't happen at other times.

 

[bmw blue]

Yes, smoke at start up is indicative of bad valve stem seals and or guides. And as it warms up it stops until the next cool down and then start-up.

 

[just_drive]

Just curious, how many miles are on these plugs?

 

[musa]

Just curious, how many miles are on these plugs?

10k thereabouts, not so sure. I'm now in the process of replacing the valve stem seals without removing the head. Also using bungee cord trick to keep the valve stem from falling down into the cylinder.

 

[mattmar1]

ok gotta ask.....how can a valve guide fall fall in to a cylinder? lol