water pump on 360

That bolt is supposed to have a thick Belleville-type washer on it. But; think about it. The coolant travels past the threads, up the bolt and fills that cavity around it. And it's under pressure. So it's desperate to get out. But if it's 50/50 antifreeze, it will eventually corrode the aluminum so bad it will make it nearly impossible to remove. So you can tighten that Belleville washer and stop the leak.... but that won't stop that chit behind it from happening.