I have a 89 Renken Cabin Cruiser, It has a 5.0 cobra engine and a cobra outdrive, Ive only had the boat for about a month. Before I ever took It to the river I called myself doing rutine maintance, at home new fluids tune up exct exct..... Then I hooked a foot hose attachment to It to check the engine before ever launching the boat, I let It run long enough to check the temp, volts, and oil gauges. everything was fine. But when I put the boat in the river it run hot. so while it was still in the water I took the main water line loose and run the engine and no water was coming in. So I put it back on the trailer, I took the water pump off te foot it looked new it was soft and undamaged. So I brought the boat back home. I had a friend assist me, he cranked the engine and I was watching with the impeller off the shaft was thrning. so I changed the water pump on the engine. fushed the engine everything was flowing well. No trash in th engine. So then I left the water pump off the foot and took a hose pipe from the engine main water line I flushed the line out and several pieces of a old impeller came out from the foot..Then I took my hose attachment once more and hooker it to thefoot once more the pump is still off turned th hose on and more pieces of a old impeller came out. I put it all back together, and run it once more in the yard. The temp never got over about 130. so I thought now ive fixed it. but I thought before I take it to the river again I need to check it without the hose, So i went to lowes and bought a large tub put it under th foot and filled it with water, I left the hose runing in the tub. to make sure i wasnt starving my engine for water, the water level is well above the screens in the tub. i did not pick up the water. so while the engine was still runing and th foot was still in the tub i hooked the hose attachment back up and it was running cool and exaust water was cmeing out again. so i pulled the hose attachment back off and it was still running cool in the tub. But when you turn the engine off and crank it again it wont pick the water back up. but with the hose hooked back up it pumps water again. The impeller fites real tight in the sleve do you tink its the wrong impeller. or theirs still trash in the lower unit. or something else. P,S, the impeller is not worn from the rubber to the shaft it fits tight.   Please do you have any insite on this problem. THANKS.... Paul......