It's hard to find any experts or forums for nissan's, but my friends 1987 300zx turbo recently overheated. It has approximately 150,000 miles. Driven again, it didn't overheat. Problem is: oil appears to be in coolant. Poop brown and stinky under pressure cap. Expansion tank appears normal color and smell. Exhaust smelled a little sweet and was pretty moist at cold, but went away once warmed up, and stayed at normal temperature today. From what I've read on the MB gassers, that's code for new head gasket. Can this be confirmed? The car is going to be winter garaged anyway, so should that be attempted by someone who doesn't know a camshaft from a fuel injector, but who's willing to learn, with my help? Or is this new engine territory? How about driveability in this state?

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1983 240D 3.0T 4-speed manual, now sold

1989 Subaru GL Wagon 5-speed Touring Edition