I just bought a 1985 mercruiser 120 I/O boat. Boat was sitting for 2 years. I did a basic tune up Oil changed, plugs, wires, cap, rotor, coil. I did not change drive oil. motor runs great when hook up to ear muffs. Let run for 15-20 min and temp barely moved. I put the boat in the water today and after running for 2 min the temp gauge was at 200. i quickly turnd boat off. and let cool down. I removed the hose going from thermostat to intake and started motor. no water came out of intake. A Large amount of black gritty sludge came out of hose.
What would be the next step in solving my problome. Is the water pump bad? Could sludge be stopping something up? How do you remove sludge? What Should I try first? please help. Any suggestions?
What would be the next step in solving my problome. Is the water pump bad? Could sludge be stopping something up? How do you remove sludge? What Should I try first? please help. Any suggestions?
