Running on the experimental edge has its price. <img src="/forums/images/graemlins/barf.gif" alt="" /> Noticed some detonation at highway speed under load, which is dang hard to hear in this truck.... dropped the ignition timing back to 0 BTDC base and drove some more.... noticed idle manifold vacuum dropped to 12 and disappeared on throttle application, but steady, so attributed it to retarded ignition timing.... concerned about elevated CHT, but didn't notice any temperature rise... however, power loss w/o boost was noticeable.

Checked the engine bay and found spit marks around the oil filler neck and stains on the dipstick tube. Pulled the oil filler cap and found a milk shake on the oil filler cap.... checked the dipstick and no water... checked the radiator and found no oil.... expansion tank down slightly.

Exhaust on cold start smells normal, but the crankcase pressure is excessive.... slight pressure through the PCV hose (normal with the restriction), but major pressure through the passenger side cross vent that plumbs into the inlet air duct and the driver side oil fill..... oil in the throttle body and more milkshake in the air inlet hose that came from the passenger side valve cover cross vent.

Bottom line - worst case is cracked rings/busted piston ring lands/holed or cracked piston on the passenger side... blown head gasket at a minimum. <img src="/forums/images/graemlins/barf.gif" alt="" />

Idle is normal... steady vacuum.... no rattles or knocks. Has anyone ever seen a blown head gasket pressurize the sump? Could I be so lucky? <img src="/forums/images/graemlins/baby.gif" alt="" />

Anyway, the rebirth will include:

this

and

that

Frank <img src="/forums/images/graemlins/shiner.gif" alt="" /> <img src="/forums/images/graemlins/rolleyes.gif" alt="" />