1961 CESSNA 150A O-200 Oil Leaking out of carburetor

[YeagerB]

Hello all!!

I have been trying to find the source of a pretty good Oil “Leak” and have found oil dripping from the carburetor box and confirmed from the carburetor. Yes, I’ve checked the wet vacuum pump, push rod tubes, valve cover gaskets, oil sump gasket, case halfs and cannot find any other source of oil. Am I crazy or does someone know what could be causing oil to come down the intake?! Engine has 360 hrs SMO.

Thanks in advance

 

[Punkinhead]

My A65 Cub does that. I assume the oil is getting pulled from a worn intake valve guide during the idle before shutdown. I can see an oil trail from the valve with a borescope. I plan to pull the cylinder this winter.

 

[d.grimm]

Worn intake valve guides. What’s your oil usage? Quart every 2-4 hours?
550 hours on brand new Continental cylinders for me.

 

[Punkinhead]

I'm travelling and can't look at the logs but I'm guessing I have about 250 hours on new millennium cylinders that the previous owner installed. Fortunately pulling cylinders on these small continentals is quick and easy.

 

[YeagerB]

Yes, about a quart every 3 hours. I loose oil a bit quicker when I am beating up the pattern about 1 every 2 1/2 (tac time). 365 hours now on new continental cylinders. I guess I'll keep running it until it starts consuming more...... keeps the belly slick.

 

[flyingmoose]

Got any pics?

 

[Checkout_my_Six]

worn intake valve guides....