Problem with cummins 350 (coolant in fuel)

[Grunex]

Last winter I bought a Cummins BCIII to put into my site truck, and it wasn't until recently that I started putting it into the truck,  well low and behold I find coolant in the fuel pump solenoid when I when to convert it to 24v from 12v.  Anyone with experience along this line?  Anyone think I might get lucky and only have a blown head gasket or would I be looking at cracked heads?   (fuel rail runs through the heads on this one)  also when I had the oil pan off I noticed a small amt of rust on the connecting rod in the 4th cylinder.   

I bought the engine as a take out engine, and kind of expected to find something wrong with the engine, but this one I'm not sure on what would cause the coolant in the fuel system.  (not that much of a rookie to think that all people are honest when making deals either. )

Thanks in advance

[kiko]

Most likey a cracked head. Fuel rail is in the head and does not cross the gasket. However, I have worked on these engines but not on a regular basis. If you have ESN I could run down the cummins trouble shooting procedure.