well anyway I'm going to chalk it up to water condensation inside the engine. It is my spare and it did sit from this time last year up until I installed it a month ago. Furthermore, when I bought the engine, I did do compression checks in a damp situation in a garage but during a storm which could account for some of the moisture that got in there. I have run this motor at idle for at least a couple of hours trying to get the weber right, so I think if it was a HG then I would've seen a lot worse in the oil pan.

'95 runner 3vze/r150f