Major blow-by....??

[19dabeast85]

I've recently noticed that when I remove the oil-fill cap (215,000 miles) while the engine is running, I get a strong stream of air in my face, almost enough to take my breath away! Anyone else notice on their F22? I checked my parts-car engine with 111,000 miles on it and it does the same thing. I assume this pressure comes from blow-by but seems like a little much to be normal......then my last few oil analysis have come back with great reports

[Chrisisiced]

I think thats somewhat normal as long as it isnt blowing oil out at you...

[ChillPhatCat]

Is it using more oil? Does the exhaust smell like oil?

[RacingEmotions]

just curious, why would you even take the oil cap off while the motor is running anyways?

[prNonVtec4u]

that's normal operation... that's actually where your PCV system comes in hand and makes sure all that blow-by air is put right back into the intake mani. through pcv valve

example through consequences, any engine w/o ANY kind of PCV system(or similar) would b blowing OUT seals all day long

[Losiracer2]

add an oil catch can if you're really worried about it. There's a DIY for that on here somewhere.

[19dabeast85]

Is it using more oil? Does the exhaust smell like oil?

Nah, not using any oil between the 3000 mile changes.

[19dabeast85]

add an oil catch can if you're really worried about it. There's a DIY for that on here somewhere.

I have one! Check out my MR for pics.

[19dabeast85]

that's normal operation... that's actually where your PCV system comes in hand and makes sure all that blow-by air is put right back into the intake mani. through pcv valve

example through consequences, any engine w/o ANY kind of PCV system(or similar) would b blowing OUT seals all day long

Yeah I understand all that just hard to see how the PCV system can handle that much volume.

[19dabeast85]

just curious, why would you even take the oil cap off while the motor is running anyways?

curiosity, to watch the cam, check for blow-by, get high on oil vapor!!

[90goldcoupe]

Air and or oil being thrown out of the oil cap hole while the engine is running is normal because it is an ohc engine.

[90goldcoupe]

curiosity, to watch the cam, check for blow-by, get high on oil vapor!!

Next time try to add oil with the engine running.

[foamypirate]

Next time try to add oil with the engine running.

I imagine it would end up something like my attempts at filling my auto trans fluid in 20 mph winds!

[bcjammerx]

yeah if blocked the pcv holes you'd blow seals...the pcv has a one way check valve in it...it lets air flow from valve cover to intake (lifts a metal ball)...but once air tries to flow from intake to the valve cover the ball drops and stop air.


Wonder how much pressure the pcv valve could take...I could guess how much the hose could take...but the valve itself...hmm

[19dabeast85]

I wonder if the reason why it's pretty common for the F22 to leak through the rear main and valve cover is because the PCV system can't evacuate the gasses quickly enough causing a small positive crankcase pressure.......anyone want to install a pressure gauge in their oil cap? I just might try it with my extra one....

Oh and my PCV valve is working properly in case anyone asks.