clearing blockage in cooling system

I recently bought a '63 sea king 15 (OMC/gale products). It gets real hot when I run it and no water comes out of the water exhaust hole. I think this is why the previous owner sold it. I figured it was the impeller but when I replaced it I found that the previous owner had already tried that - the impeller was brand new. However, I did find a piece of the old impeller stuck in the impeller housing. I figure the old impeller came apart. Removed that piece but still have the same problem. Another piece of the impeller must be stuck somewhere further upstream... how do I flush it out? If I shoot water up the water pipe in the exhaust housing I'm afraid it will force the blockage into the power head... anyone have any ideas? Thanks!

Re: clearing blockage in cooling system

I don't think you have any choice but to take it apart and find the blockage. I am not familiar with that motor, exactly, but one thing I will virtually guarantee is if it is a part of the old impeller stopping things up, it won't flush it's way out on its own. Maybe you will really luck out and it will be at the bottom of the tube at the output of the water pump? <br /><br />John

Re: clearing blockage in cooling system

I too, am not too sure about your motor but you might want to look for a frozen or blocked thermostat (if it has one)....