Hello. When I run across the lake and stop to fish everything is good. If I fish for 20-30 minutes and start up again my solid overheat alarm goes off immediately. I have to high idle it for 10 seconds or so then the alarm stops. Right when I start my engine the digital temp reads anywhere from 742 to 180 degrees. When I high idle it drops fast and once it gets below 136 degrees the alarm stops. This is the only time the solid alarm sounds. What could be the problem? Thank you.
Check thermostats. Would be my guess.
Roger Jenks Jr
2021 Bass Cat Lynx
250 Pro xs 4S Serial # 3B010758
Just to be sure: Are you starting the engine within 5 seconds of turning the key "on"?
Water pump was last replaced (when)?
Current Water Pressure at idle?
(working on the presumption that you meant to indicate temps anywhere from 142-180, not 742 - 180)
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
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Originally Posted by EuropeanAM
Just to be sure: Are you starting the engine within 5 seconds of turning the key "on"?
Water pump was last replaced (when)?
Current Water Pressure at idle?
(working on the presumption that you meant to indicate temps anywhere from 142-180, not 742 - 180)
Water pump is new. I'll have to check the water pressure at idle. No, sometimes right when it starts the digital temp reads anywhere between 180-742 degrees. This doesn't happen on initial startup. Only when I make a run then stop to fish and start back up after 30 minutes to an hour. Temp drops to normal within 10 seconds or so when I high idle.
If you're seeing anything within a few hundred degrees of 742... you have a sensor or harness malfunction.
Good idea to get the Run History and Freeze Frame (Fault) History printed (from the Computer Diagnostic System), as those report will likely contain information to help narrow down what's occurring.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
I'll get those checked ASAP. Thank you!
I was assuming you meant 142-180 as well. At 740 It would look like a volcano.
Roger Jenks Jr
2021 Bass Cat Lynx
250 Pro xs 4S Serial # 3B010758
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