Water came out of the bolt hole for the valve cover? Sounds like someone broke a bolt and tried to drill it out, went to deep and drilled through the water jacket.My older brother used to think he was the original Mr. Goodwrench, he did this to a 250 cu.in. 6cyl. engine.Couple ways to fix this, take the head off and bring to a machine shop they can fix it, or do the easy cheap way, drain the water to a level about half way down the radiator when you take the bolt out, then when you put the bolt back make sure and put some sealer on the threads around it and snug it down good, not to tight just good and snug then fill water back up. You'll be ok.
