JacobChevys

Put the car in the garage about 6 years ago due to the 3rd cylinder that would continuously oil foul out the plug and start to misfire and smoke. I’d say within 30 min the plug would be fouled.

Decided to get back into the car game after life got in the way for a bit.

Anyways I Did a compression check and all cylinders were around 160psi. Also changed the intake and exhaust valve seals with new GM ones on that cylinder. No changes what so ever, same problem still. Will be doing a leak down test sometime this week. The engine doesn’t smoke out of the oil fill cap only will smoke out the exhaust once that spark plug gets fouled. Which leads me to believe possibly a ring land is broken or the oil rings are worn.

I have hundreds of 1/4 mile passes on the engine which is all original about 70k miles. Stock
bottom end and stock heads as well.

Will know more once I get the leak Down test, just wanted to see if there’s anything else I’m missing. Can valve guides cause an issue like this? Could it be a cylinder head issue? Or most likely a bottom end/ring issue?

G Atsma

Oil gets into the chamber either past the guides or rings.
If you replaced the guides with (good?) new ones, unless there's a score down the cylinder wall, it has to be rings.
Process of deduction....
The hundreds of 1/4 mile passes usually takes its toll in some way.

SAPPER

iTrader: (10)

Broken ring land most likely. Just not on the top ring, which is why you seem to get some compression.
But the key statement is,
"I have hundreds of 1/4 mile passes on the engine which is all original about 70k miles. Stock
bottom end and stock heads as well."
So 2+2 = 5

JacobChevys

Agreed I believe it’s a piston or ringland issue as well. Just curious if I was missing anything else. Motor was always a “potent” one. About 9-10 years ago I actually clicked off a 12.9 with nothing but an exhaust cutout at the rear axle.

I will be acquiring a LQ4 that’s in the works relatively soon, which I believe is a better route for me to take considering the setup I want to go with.

01CamaroSSTx

iTrader: (3)

Might just be worn rings though and you could probably make that repair without pulling the engine but with that many passes on the engine it's probably that time.

RB04Av

Might just need sealer on the threads of the intake rocker bolt.

Kawabuggy

iTrader: (1)

I broke several ring lands in a 6.0 recently.. The land that broke was between the 2nd compression ring, and the top of the oil control ring stack.. I broke that same land on several pistons.. Yes, it was smoking like a chimney before I pulled the motor and replaced all the pistons.

Old Buzzard

That problem have any relation to 30# of boost???