After running it for a few minutes (barrel test), it starts to sputter and misfire, the cylinder head gets hot (to the point where you cannot hold your hand on it for a slow count to 6) and then it quits. There is water coming out the telltale.
I have a new impeller and thermostat installed, and I replaced the fuel pump as the old one was in questionable condition. I have also run water from a garden hose through the thermostat hole and the copper pickup tube in hopes of clearing any blockage, and the water does get through.
Any tips as to how I should proceed from here would be greatly appreciated. Thanks!