trevorsmith82

Today checking my oil air filter etc, I came across oil blow back on my air filter, only on the side where the air filter breather is. I know its coming through the air breather is, I just need to know whats causing this and should I be concerned.

Engine btw is a 2.5 iron duke I know its shameful

Apeiron

Excess crankcase pressure and/or bad PCV.

trevorsmith82

PCV was replaced recently though it might be a dud, how would i deal with the excess crankcase pressure if that was cause?

thanks

Damon

It's the PCV system almost certainly (otherwise the rings are shot and it's rebuild time).

Pop the PCV out of the valve cover with the engine idling. See if it's got strong vacuum at the end of the PCV valve where the hole is (it should). While you're at it, see how much blow by is drifting out of the PCV hole in the valve cover. If it's chuggign like an old freight train, the rings are shot and you're all done. Hopefully that's not the case.

Sometimes the PCV valve is fine but the line connecting it to the intake is plugged up with decades old oil schmutz. Old Pontiac V8s were famous for this. Maybe the Iron Duke as well? Worth checking anyway. That includes checking the PCV hose nipple on the intake/carb as well. When they plug up like that it's usually about everything that plugs up!

trevorsmith82

I dont think its rebuild time, this engine only has 64,000 miles on it unless letting and car and engine sit for period time can cause rings to go bad. Its only soaking the air filter on the side where the air breather connects to the air cleaner.
Ill do the test you instructed and see whats going on here thank you!

punkmaster98

iTrader: (5)

Im having the same problem. ill try that too.

hondorian7

i had this problem and if its TBI take of the TBI and check where the pcv line goes in. mine was mostly clogged not getting enough vaccum but did have some. after i cleaned it good and attached everything back up i put a breather tube on the valve cover going to the air filter and havent had any problems or oil in the filter since then. you dont need the breather but i wanted to put it on to help with oil on filter.

trevorsmith82

Ive done so many things to the engine since my last post
I did a compression check and the rings check out fine
I went through rebuilt the throttle body installed a new pcv valve with a catch can
And I hate to say it still blows oil
It has so much pressure in there it like to pop out my pcv valve and blow oil through my valve cover gasket