Subject: water in oil and out exaust big time
Question: 87 mit pickup 2 liter manual trans
truck runs very well but water is mixing in the oil pan and a lot blows right out the tail pipe
i changed the head gasket head seemed fine no visible cracks. is there anything else it could be but the block? thank you al russo
Answer: Al,
From how you described it, it would seem that you do have a cracked block somewhere. It doesn't take much of a crack for your coolent to seep through. Keep an eye on your coolant level and see if you seem to be loosing it at a steady rate.

There is a VERY remote chance that the gasket on your oil pan is not making as tight as a seal as it could. When you let your truck sit over night, moist air could condense in your oil pan due to a weak oil pan gasket seal. That is a shot in the dark, but it is possible.

Your engine is pretty old, and I'm assuming you have a lot of miles on it. If it still runs well, and only a little coolant is being lost, I think you'll be fine. Just keep a close eye on it. If it gets really bad, you'll most likey need an engine rebuild or replacement.
Good luck!