cjoenck

Yesterday evening I took the intake system apart because I noticed oil dripping from the intake crossover. I understand overfill can get oil into the intake system, but what other causes should I be looking at? I am pretty sure overfill is not the issue here. Thanks

Steve Weiner-Rennsport Systems

Hi,

Engine oil found in the intake manifold comes from the oil tank since its breather is connected to the manifold.

The only way oil finds its way in there is either by an accidental overfill or worn/broken rings which allows the engine to pressurize the tank which pushes oil into the breather tube.

A leakdown test will tell you the source of the oil you find.

Indycam

The case is vented to the intake , some oil is going to find its way into the intake .
The scavenger pump picks up oil and air and pumps them into the oil tank , the air is vented from the tank into the intake . The oil that gets put back into the tank is a foamy / frothy mess . If you were to have a look see inside the case at high rpm you would see a tornado of oil mist .

elbeee964

I like that imagery!

cjoenck

Thank you for the quick reply. What I think I hear is that a little oil is normal, a lot of oil is either overfill or broken/worn rings. I will check oil levels again - it is always possible that I am a complete moron and I may be reading the dip stick wrong plus a faulty oil level sender.

Wouldn't broken rings show other symptoms like blue smoke?

Once I get it all back together, I will have the leakdown test done.

Thanks