Dip Stick Blow By??

It seems I have a blow by leak out of the dip stick check tube. Anyone ever seen this before? It's not the distributor or oil filter o rings either? By the way, it's a spray all over side of the engine too.

A fix??

Sure - clean out the CCV system, and recheck.

Blowby is fairly normal (I think "peak" ring sealing for a racing engine approaches 98.5%, production engines are happy with 90% or so,) but the CCV (or PCV, on older vehicles) system is designed to mitigate that, by maintaining a slight "negative" pressure in the crankcase and venting it into the intake stream.

The CCV setup on the 4.0 tends to clog, and wants cleaning. Blow out both of the CCV lines into the valve cover with some carburettor cleaner, blow out hte baffles in the valve cover proper (change your oil!) and make sure there isn't a "breather sponge" that's supposed to trap oil that didn't get clogged (I don't think there is, but someone like me may have added one. I have that habit...)

Once you've done all that, check to see if there's a blowby issue at the dipstick again. Good news - you're losing it out the dipstick, which means you aren't blowing a valve cover gasket - or worse, an oil sump gasket...

5-90

It must be the cover baffle as it has almost new CCV tubes and hoses. I've been wanting to pull it to clean and paint it to make it all purdy. Now me has an xcuse!