I have a mercurey 40hp, bout a 1998, yesterday while on the lake it started a ran fine.....for about a half mile then started to stall or cut out but never did, it did this several times. I would stop, fish a while and move and it repeated, at about a half mile. First thing comes to my mind is its happening when it gets good and warm...........i use stabil religiously..........any opinions?
oh yeah, it cut off while idiling at one stopping point
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would the problem not be consistant if it were carbs, i mean it cranks fine and runs great for about a half a mile..............also it dont spit and sputter like a carb problem, its like total loss of power, but its only for a second, and its intermittent..........i was afraid to go to far to test what would happen if i ran it like a rented mule
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Yeh....I can follow your thinking and it makes sense. But I had a 50 Merc one time that was doing like yours...it might do it three times in one day....then it might run great for 3 or 4 weeks and do it again. You just never knew when it was going to do it. I had the carbs cleaned up and new kits put in them....that cured it....so I dunno....
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I've spent most of my life fishing.....the rest I've wasted. Lifes too short to only fish on weekends.
make sure everything is tight.
Get a cheap test light
first have someone to turn key switch to start position take test light check red wire going to starter if it lights up but want start bad starter, if no light there go to siliniod check yell/red wire if you got power there bad siliniod, if no power there go to key switch check yell/red connection there, if no power on yell /red wire with key in start position replace key switch. if power at the key switch check neutral safety switch. hope this helps
I'm not a pro, but could it be that after a half-mile that the contents of the fuel filter could be sucked back on the filter with the vacuum from the fuel system. I could be wrong but keep it simple and do minor maintenance on the motor and see if that helps. Good luck and keep us informed. Rollcaster........................
I'm with rollcaster, I'd do the cheap dumb stuff first. If there was any trash sucked into the carbs it could float free while at rest only to get sucked back up against a high speed jet when under power. If it's solid matter all the cleaners known to man wont help. The motor is 10 yrs plus old, wouldn't hurt to do the carbs. Merc carbs have the reputation of being finicky if you don't know them that well, best done by a reputable pro. Keep us posted please.
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Prisoner of the White Lines on the Freeway
Fishin my life away.
thanks for the tips guys, the carbs were rebuilt probably 4 or 5 years ago but that is a significant amount of time........i'll check the tank first and start up
__________________ experience is something you get right after you needed it
I had a car that demonstrated similar tendencies. Turned out to be a blockage in the fuel system. Starver for fuel, it would quit. Sit for a few minutes, it would crank and run for another few miles & repeat.
Look at your serial number. If it is below 0G919929, rebuild your fuel pump with new gaskets, diaphram, and especially check valves. Kits from Merc (about $20) include new style check valves and instructions for installing them.
merc 40 prob
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