Bought a 73 Lund President w a 302 Mercruiser. Took it out for first time and in about 15 mins the temp gauge pegged. Shut it down and got towed back. Pulled the lower water pump impeller out and it was literally rubber dust, with a melted housing. I'm know for a fact the previous owner ran it without ear muffs hooked up. So I replaced the entire water pump kit. Reassembled and ran it with earmuffs to test. Water getting up to the motor now, confirmed by pulling a hose off at the t stat housing. It still got hot however. When it reached about 200 I shut it down. (Not sure if it would have gotten hotter).
Side note, the exhaust bellow on the stern drive is missing. Will this cause overheating issues for the lower unit? Does the lower unit get cooled by water/exhaust running through the unit then out the impeller?
I Pulled the UPPER water pump. No obvious damage to the impeller. Pulled t stat. No obvious damage but will likely replace just to be safe.
I noticed in the manual it says if the lower pump impeller is damaged, then the exhaust shutter valve in the exhaust elbow needs serviced as well. How factual is this? Would/could this be cause for it still running hot? Is this another 2 day project like the lower water pump was? (Could NOT get the driveshaft splines lined up. MAJOR PITA).
Assuming I don't have a gauge that's off, what else should I be looking at for the running hot condition?
Thanks
Side note, the exhaust bellow on the stern drive is missing. Will this cause overheating issues for the lower unit? Does the lower unit get cooled by water/exhaust running through the unit then out the impeller?
I Pulled the UPPER water pump. No obvious damage to the impeller. Pulled t stat. No obvious damage but will likely replace just to be safe.
I noticed in the manual it says if the lower pump impeller is damaged, then the exhaust shutter valve in the exhaust elbow needs serviced as well. How factual is this? Would/could this be cause for it still running hot? Is this another 2 day project like the lower water pump was? (Could NOT get the driveshaft splines lined up. MAJOR PITA).
Assuming I don't have a gauge that's off, what else should I be looking at for the running hot condition?
Thanks