Hi all. 1988 Cobra 3.0. New impeller done at start of season. It didn't fail just routine maintenance. I had left my radio on and drained battery so I jump started at dock and let it idle for 10-15 min. Noticed temp gauge heading for the red and shut it down. My repairman came down and suspected intakes had weeds blocking. He blew out then system through the hose to the stern drive at tstat. After that it pumped water. Used it for a weekend all well. Yesterday went out and it overheated again. Pulled hose off tstat housing and no water coming from pump.
Pulled boat. Back flushed system and no debris present. Ran boat on muffs at idle and it pushed strong water flow. Let it run 30 minutes idling no issue. Back it into the lake on trailer and started it, no water flow at the engine again. My repair guy pulled the impeller the first time this happened and it was good.
I'm at a loss to figure this out. Thinking of replacing impeller again and flushing it with the impeller out of boat.
This boat has no oil coolers or heat exchangers that could plug up.
What say the experts? I'm baffled.
Pulled boat. Back flushed system and no debris present. Ran boat on muffs at idle and it pushed strong water flow. Let it run 30 minutes idling no issue. Back it into the lake on trailer and started it, no water flow at the engine again. My repair guy pulled the impeller the first time this happened and it was good.
I'm at a loss to figure this out. Thinking of replacing impeller again and flushing it with the impeller out of boat.
This boat has no oil coolers or heat exchangers that could plug up.
What say the experts? I'm baffled.
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