Oil in top of carburetor

[Pmc3614]

I have a 7.4 mercruiser , had trouble starting it this morning and when I pulled of the spArk errester there was oil on the top the carb and oil film on the errester. cleaned it up and ran OK, not sure what caused this

 

[HT32BSX115]

I have a 7.4 mercruiser , had trouble starting it this morning and when I pulled of the spArk errester there was oil on the top the carb and oil film on the errester. cleaned it up and ran OK, not sure what caused this

Howdy,

Welcome aboard!

A picture might help, but usually, the oil breather tube will allow a small amount of oil vapor from one of the valve covers to "condense" oil where it enters the intake.

Doesn't hurt a thing unless there's a lot. If that's the case, (with a high time engine) you might have excessive blowby.

Regards,

Rick

 

[Bondo]

Ayuh,..... Welcome Aboard,.... Rick is exactly right,....

The only way for oil to get there is from the crankcase breathers,...

 

[Pmc3614]

Thank you both that's helps me look in the right direction, seems it may be excessive but I will Monterey it and see how it goes.Glad to be aboard!

 

[shaw520]

An over filled crank case,.. a clogged crank case vent,.. or excessive blow-by, 3 things that will cause oil to be forced up the breath tubes.

 

[tango13]

I found oil on the top of my Q-Jet and realized it was probably from the breathers or from the fogging oil during winterization...