How to check for Blow-By?

[frankn88]

I'll spare you all the history, but here's what's going on: Engine had a valve job last summer. 550 hours. Immediately following valve job, at high speed/on plane, it appears that oil is leaking out from a gap in the intake manifold seal (RTV) at the back of the engine. According to the opinions I've received so far, this was caused either by: faulty installation of the intake manifold, or blow-by causing the seal to blow out. There is also some (not a lot) of oil seeping out around the PCV valves in the valve covers, but the breather tubes do not appear to be splatting oil into the flame arrestor.
So, before I remove and reinstall the intake manifold, I would like to determine what exactly is going on. I do not have the equipment for a leakdown test (I don't think I do anyway - I've got a compressor and a push-in compression tester?). What can I do to be reasonably assured I either do or don't have blow-by? Just a compression test? A wet-compression test? A leak-down test? Fairy dust? Thanks.

 

[scoflaw]

I wouldn't be concerned about blowby, cause it certainly didn't blow your seal out. You should be using rtv sealant on the china wall, not the rubber gasket that comes with the intake gaskets. If your valve covers are vented, there should be no pressure in your crankcase. See what you have going on back there with a light and a mirror, sometimes you can clean the area up with solvent and squeeze some rtv in the void.