Disturbing issue showing up on my 2021 Merc. 115 hp, CT. Purchased new, from dealer, delivered/installed July 2021. I have about 250+ hours on it.
Oil/lower unit oil changed at end of every season. Plugs pulled, checked, engine fogged also. Fuel filter changed 1.5 years ago. Both batteries good, charging sytem fine. Engine temp runs about 135-140 @ 4000 rpm cruising. Oil pressure steady at around 45 psi. Idles great, accelerates great, is not using oil. There are no indications of electrical interruptions to the motor as my gauges, including my GPS speedometer, remain steady.
so what happened:
Friday we were heading down to the Kent Narrows (chesapeake bay) from my marina. About a 1.5 hour trip @ 4000 rpm. About 1 hour in, I get a stumble. WTF. Continue on.....another 10 mins....stumble........f%+k ! ... before throttling back for the channel entry, maybe one more time. No engine beeps. Once at the 6 mph limit and all the way to the restaurant, no issue. Tank was filled before we left. Checked oil level, maybe a 1/4 qt down. So...
We leave after eating, leave the channel, back up to 4000. This is where it gets weird. About an hour into the trip back, the scenario begins to repeat itself. This time I'm watching my smart craft oil pressure/water temp. They're all normal. I didn't think to monitor my fuel flow for any sign. The 1hour thing?....Coincidence, I guess.....you tell me.
I have not had a chance to investigate further. I will be replacing that fuel filter and hope I see gunk in it. I will be checking the tank and feed line for gunk. I will be checking my fuel line, bulb, and connector for issues. Also, just hoping maybe water contamination....dunno.
Other than that.....what else.
Single engine out in the bay....crap.
should add, the pontoon is an '06 model, plastic tank.
Oil/lower unit oil changed at end of every season. Plugs pulled, checked, engine fogged also. Fuel filter changed 1.5 years ago. Both batteries good, charging sytem fine. Engine temp runs about 135-140 @ 4000 rpm cruising. Oil pressure steady at around 45 psi. Idles great, accelerates great, is not using oil. There are no indications of electrical interruptions to the motor as my gauges, including my GPS speedometer, remain steady.
so what happened:
Friday we were heading down to the Kent Narrows (chesapeake bay) from my marina. About a 1.5 hour trip @ 4000 rpm. About 1 hour in, I get a stumble. WTF. Continue on.....another 10 mins....stumble........f%+k ! ... before throttling back for the channel entry, maybe one more time. No engine beeps. Once at the 6 mph limit and all the way to the restaurant, no issue. Tank was filled before we left. Checked oil level, maybe a 1/4 qt down. So...
We leave after eating, leave the channel, back up to 4000. This is where it gets weird. About an hour into the trip back, the scenario begins to repeat itself. This time I'm watching my smart craft oil pressure/water temp. They're all normal. I didn't think to monitor my fuel flow for any sign. The 1hour thing?....Coincidence, I guess.....you tell me.
I have not had a chance to investigate further. I will be replacing that fuel filter and hope I see gunk in it. I will be checking the tank and feed line for gunk. I will be checking my fuel line, bulb, and connector for issues. Also, just hoping maybe water contamination....dunno.
Other than that.....what else.
Single engine out in the bay....crap.
should add, the pontoon is an '06 model, plastic tank.
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