88 740 Turbo wagon
265,000
bought used at 125K, wife thought I was crazy.

Crankcase box removed and cleaned, all related hoses and fittings too. When I disconnect hose to intercooler and blow through it, air exited through the oil fill cap. So I replaced the cap gasket, but it still erupts and drips on exhaust. Especially at highway+ RPMs. Could a needed tappet setting cause the excessive pressure?

Otherwise she runs like a bear.

Help!

 

Normally valve adjustment won't cause extra pressure.Does the oil cap fit loose or tight?None of the hoses for the crankcase system are plugged?Did you install a new flame sheild?

 

Cap fits very tight with new gasket. The oil is QS 10/30 and is up to proper level. There never has been a flame shield since I've maintained, just the 1/2" plastic connection that has the nipple fitting to TB. Blowing through the line to crankcase (with cap off) air comes out oil filler.
Nothing appears blocked, hence my bafflement. For oil to want to come out cap like volcano, something is under pressure. On some cars the valve cover has an internal shield that prevents splashing and the ability to see the cam, not the Volvo.

 

My bad I forgot it was a turbo while I was writing the post.Turbo's don't have the sheild.There has got to be something plugged somewhere its just a matter of finding it.