Sigma engine : oil dripping from the inlet manifold

[ChristopheC]

Hi all,

During the maintenance, I noticed some drops of oil on the bottom side of the inlet manifold. The engine is a standard sigma 125 (Academy car - season 2008). There's no oil catch tank. 

The engine uses some oil at a non-alarming rate : 0.5 to 1 liter  for 1000 spirited road miles but can burn 1 liter during a trackday. It seems to use more oil if the level of oil is topped to the max, therefore I try to keep a half level (between min and max). The engine is running good, no smoke.

Could the Crank Pressure Release Valve be stuck ? I had a look but it seems I have to remove the whole plastic manifold and some water pipes to get there... quite an annoying job just to "have a look". Have other members had this issue ? 

Any tips (or procedure) in order to remove just the essential parts ... before dismantling everything to reach the valve ?

Is it a known problem ?

Thank you

[Ivaan]

I don't know the Sigma engine, but isn't it more likely to be a leak from the camshaft cover gasket, just running down the front of the intake manifold?

[ChrisC]

The oil breather is located under the inlet manifold.   My sigma uses no oil on the road, but track days the catch tank fills up with some nasty stuff. 

I bet you have a split hose on the oil breather under the inlet manifold.