Howdy!
Twin Mercury 250 EIF, 1997. Currently in Belize and there is very limited service opportunity so it's up tome to fix this myself and any help is enormously appreciated. Starboard engine runs fine. Port engine randomly looses rpm. Sometimes dies and sometimes picks back up. I was finally able to make this happen consistently and here is what it is doing: at 4200 rpm, it runs fine 6 seconds then immediate rpm loss to 1300 rpm. 8 seconds later, it revs right back up to 4200. I went through a couple of dozen cycles and it was very consistent: 6 seconds on, 8 seconds off. Up until this time, it was a random event and might happen every ten minutes and might not happen for an hour. Fuel down there has ethanol. New bulbs and fuel lines to the engines. I cleaned fuel filters about an hour before I got the rpm pattern and they had a little brown in the bottom but no water. Any help is extremely appreciated. I posted this a couple of weeks ago but now, maybe the 6 seconds on and 8 seconds off pattern will be a better clue.
BTW, I tracked the previous electrical issue to a connection and redid it. It's always the last place you look.
Thanks!
Twin Mercury 250 EIF, 1997. Currently in Belize and there is very limited service opportunity so it's up tome to fix this myself and any help is enormously appreciated. Starboard engine runs fine. Port engine randomly looses rpm. Sometimes dies and sometimes picks back up. I was finally able to make this happen consistently and here is what it is doing: at 4200 rpm, it runs fine 6 seconds then immediate rpm loss to 1300 rpm. 8 seconds later, it revs right back up to 4200. I went through a couple of dozen cycles and it was very consistent: 6 seconds on, 8 seconds off. Up until this time, it was a random event and might happen every ten minutes and might not happen for an hour. Fuel down there has ethanol. New bulbs and fuel lines to the engines. I cleaned fuel filters about an hour before I got the rpm pattern and they had a little brown in the bottom but no water. Any help is extremely appreciated. I posted this a couple of weeks ago but now, maybe the 6 seconds on and 8 seconds off pattern will be a better clue.
BTW, I tracked the previous electrical issue to a connection and redid it. It's always the last place you look.
Thanks!
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