I pulled it off and removed the end caps. I blew it out with compressed air until about dry. I flushed the coolant side out with fresh water. I plugged the hose that goes to the thermostat and made up a fitting for the other coolant hose so I could attach a water hose to it. Filled it with water and then pressurized it for about 15 minutes but never saw it leak a drop. Water pressure is about 60 psi. Maybe I did'nt wait long enough or maybe its gotta be hot to expand the metal enough to leak. What do you all think? The last time I ran it was about a week or so ago and I let it get to 140 degrees, cut it off and drained the seawater side of the heat exchanger side out then. I'm baffeled!
