Oil in Exhaust Options

[Mikemo44]

Hi All, I have burnt and unburnt oil coming out of the exhaust on cylinder 2. Compression and leak down tests were both good. Looking for suggestions on how oil could be getting in/exiting the exhaust? Some searching suggests a worn exhaust valve guide?

The car doesn't have an exhaust on it, so I am able to put eyes on the exhaust port.

Thanks,

[Superhawk996]

Going to try to offer some constructive advice without being critical.

There is a lot of discussion here without measured numbers. Ie subjective.


To measure properly you need a split ball gauge and a micrometer. A less accurate way to measure is to use a dial indicator and measure at the valve head (at approx valve lift) and wiggle the valve side to side. Take 1/2 if that measurement and that is a rough approximation of your valve to guide clearance.

The fact that you had to hammer the valve out is a bad sign. Likewise compare that valve stem to the other. Notice a difference?

That cylinder has been burning oil for a while based on the build up in the combustion chamber. Not sure if it is the lighting but the cylinder with the problem - the intake port appears to be wet looking? What is that. Look for head cracks around the valve guide.

The fact that there appears to be RTV around the cylinder to head interface is another bad sign. Not sure what that RTV is doing there.

What does the cylinder bore look like? Since you have it torn down at this point - I would actually pull the cylinder and inspect the rings to make sure you don’t have a cracked ring.