Pressurized crank case?

[68383]

Can someone tell me what symptoms I'd my engine would have if the crank case was pressurized, as well as what would cause the crank case to become pressurized?

Here's what I've been experiencing, which is what makes me ask:

- The engine idle was rough.
- I noticed some fumes coming out of my dipstick tube.
- I removed the repro, chrome breather (attached to a hose going to my air cleaner assembly) from my valve cover.
- Fumes were coming from the hole in the valve cover. The engine idle sped up slightly and it ran more smoothly.
- I inspected the inside of the breather and didn't see any obstruction.
- I removed the hose from the breather to the air cleaner assembly. It wasn't collapsed and there was no blockage.
- Then I replaced the hose and chrome breather.
- It seemed like I had choked the engine and fumes started to come out of the dipstick tube again.
- I replaced the chrome breather with the one I pulled off my engine last fall.
- Before installing the old breather, I inspected it. It didn't seem to have any issues.
- The engine behaved the same with the old breather as it did with the chrome breather.

I'm hoping this is unrelated... When I shut the car off, coolant was flooding out of the overflow tank I installed a couple of years ago. The radiator three row radiator has less than 1,000 miles on it and I haven't had any issues with the 16lb cap before. Someone mentioned that if there's a problem with a head gasket, my cooling system could be leaking into my oil system and pressurizing the crank case. I didn't see any white smoke coming from my exhaust pipes.

Tonight, I checked the oil to see what it looks like. The dipstick showed that it was nice and clean, like honey. The oil was changed last November and I've only driven the car about ten miles since then. I also checked the air cleaner assembly and filter (maybe 100 miles on the K&N filter I installed). The air filter was stuck to the inside top assembly, but it wasn't bound, like it was rubbing the inside of the air cleaner. It also seemed to fit fine inside the base of the air cleaner assembly.


I noticed the fumes coming from the dipstick last November. I pulled the PCV over the winter. It rattled when I shook it, but I replaced it for good measure anyway. The new one rattled before I put it on, but I can check for vacuum from it.

Any other ideas on my problem?

Thanks,

 

[Meep-Meep]

The only thing that would cause a lot of pressure is major blow by with a sealed crankcase. I have heard stories of the fuel rich vapor in the crankcase igniting and blowing the valve covers and oil pan off the engine but never actually seen it.

The proper way to check for low pressure in the crankcase with the PCV hooked up is to hold a piece of paper over the breather hole and see if it draws it in. Did you verify flow through the breather in both directions - even as installed in the valve cover? The push in tube is not being blocked by the baffle or grommet inside the valve cover is it? PCV is hooked to manifold vacuum and is sucking air?