This afternoon, I was looking around under the hood of my truck, searching for the source of the gas smell in my cab and found something that was a lil strange. I noticed that a liquid had been running down the inner fenderwell, right under the airbox so I opened the airbox to find out what it was. Turns out, it seems to be a mixture of water and oil from the crankcase breather tube... I realize a lil bit is prolly normal, but this is enough to soak the breather filter, stain the air filter and fill up the airbox to the point it ran out the drain hole and that seems excessive. So, I was just wondering if this was normal or if anyone might know what's causing it to happen? And also, could this be what I'm smelling inside the cab, because It has a really strong gas smell to it.


Thanks in advance for any help someone might be able to offer.

 

Check your pcv hose and valve and make sure they are properly connected. Without that you will get blowby and fumes.

 

^^^^^What he said....

 

Well, I figured out the source of the smell and it was what ya'll said. The pcv wasn't all the way inserted into the valve cover. The problem with the oil isn't anywhere near that valve though. It's just a hose that comes from the oil filler neck and runs into the airbox under the air filter...no valve or anything anywhere on it...

 

That would be the air intake for the PCV system.

After all, what the PCV valve allows to be sucked into the engine to be burned has to be made up somewhere. At least they're getting smarter now, and filtering the input.

The ol Jeep just has a mesh breather on the oil filler cap. I'm sure no dirt can possibly be getting sucked into the rebuilt and getting doggone hard to get parts for 304 through the equivalent of an oven hood screen. :-)~

But all seriousness aside, as the engine ages - it is possible that the blowby exceeds the average capacity of the PCV system - resulting in the oily filter observed.

 

Alright, I appreciate the help.

 

Look, oil is going to get into your intake one way or another. A clogged PCV valve would cause the crank case pressure that's not being sucked out via the upper intake manifold, will be forced to push it through that oil fill tube.