Does the crank case push pressure or pull a vaccume?, I did something stupid.... Options

[VaccaRabite]

So some of you may remember my thread a couple weeks back that the oil filler cap disappeared during a spirited drive a while back. I have 2 other caps, but they are the wrong size (grrrr).

I drove a couple times and not much oil came out, but a little did. So I figured some aluminum foil where the filler cap should be would keep the small amount of oil the comes out from happening.

So after applying some heavy duty foil, I fired her up and went for a drive for about an hour. Came back and the FOIL WAS NOW GONE! There was foil around the lip of the filler, but the foil the covered the opening has either been blown off, or sucked into the crank case.

So... yeahhhhhhhhhh. (IMG:style_emoticons/default/icon8.gif) (IMG:style_emoticons/default/stromberg.gif) (IMG:style_emoticons/default/slap.gif)

Engine ran great. No changes to oil pressure or oil temps. Clearly I need to drain the oil out and also pull the tuna can off and look around.

So. How boned am I?

Zach

[Spoke]

I would think the crankcase would be under pressure unless you have vacuum from the intake connected to the PCV. If you have a catch tank and filter, the crankcase would be under pressure at all times.

For the tinfoil cap, if it blew off I would think it would be jammed in the fan and likely squished together along some of the vanes as centrifugal force would flatten the foil against the vanes.