Black smoke out back, engine splutter

phunk

It's possible your cooling system just had some air still in it, and was able to empty the overflow on cool down after expelling the air?

I've only seen a blown HG on a VQ once and it did not mix water with oil. What it would do was allow combustion pressure into the cooling system during full throttle, which would cause the coolant reservoir to overflow (and mist coolant on the windshield through the vented hood), and then after cool down it would draw the reservoir empty.

__________________