500EFI Overheat
#1
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had an odd issue with starboard motor this past weekend. It would overheat at idle and cool down during cruise/WOT. Anyone ever have this issue? Where should I start?
some things I have ruled out by logic, let me know if you agree/dis-agree. Don’t think it’s a blockage because at cruise/wot the water pressure would spike and I would think flow go down and overheat. By that same logic I have kinda ruled out t stat.
Im thinking it’s an impeller issue or leak maybe in strainer cover pulling in air? The flow difference is noticeable when compared to port motor at idle.
some things I have ruled out by logic, let me know if you agree/dis-agree. Don’t think it’s a blockage because at cruise/wot the water pressure would spike and I would think flow go down and overheat. By that same logic I have kinda ruled out t stat.
Im thinking it’s an impeller issue or leak maybe in strainer cover pulling in air? The flow difference is noticeable when compared to port motor at idle.
#2
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Impeller is worn or housing. Not drawing enough when idle, when cruising water is being forced in and it will cool. Sometimes the slightest scratching or wear in the housing will cause 5-10 psi difference. Just my opinion. Should be easy fix. Buy kit and install. 1/2 hour job tops. Soap the impeller when installing
#3
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Impeller is worn or housing. Not drawing enough when idle, when cruising water is being forced in and it will cool. Sometimes the slightest scratching or wear in the housing will cause 5-10 psi difference. Just my opinion. Should be easy fix. Buy kit and install. 1/2 hour job tops. Soap the impeller when installing
#4
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Id order two.....spare one on the boat never hurts
#5
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good call, I installed a brand new housing recently, it had a hairline crack in the boss cavity the way it was manufactured. Leaked and threw water all over the place when spinning faster then idle....lol. Good to have spares.
#6
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Pulled apart the pump. Everything looked good. We replaced it anyways. Haven’t had the chance to dunk it back in. We did notice that there are significant cracks in the sea strainer lid. See picture. Wondering if that could lead to pulling in air. Ordered a new lid already.
#7
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#8
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Pulled apart the pump. Everything looked good. We replaced it anyways. Haven’t had the chance to dunk it back in. We did notice that there are significant cracks in the sea strainer lid. See picture. Wondering if that could lead to pulling in air. Ordered a new lid already.
#9
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I had a similar issue with mine no cracks but the outer lip of the lid that holds the O-ring in place had deteriorated, I rebuilt them both
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