I have a gl wagon that just lost a bunch of power and started spitting exhaust out of the oil fill and dip stick. there's no water getting into the oil either. I was told it is either a blown head or just the gasket but, in all my expiriences a blown head or gasket dumps water into the oil too. any one have a better diag. ?

Compression test it.

Sounds like you have alot of blowby past the rings. Maybe one stuck ring or more, or a broken ring.

 

 

nipper

Headgasket failure; cylinder to cylinder, cylinder to oil passage, cylinder to water passage, cylinder to oil return gallery, cylinder to the outside of engine, oil passage to water passage, oil passge to outside, water passge to outside, water passage to oil return gallery.