USMarine50hp
New member
I have a 1991 US Marine, Force 50 hp outboard engine. The engine is difficult to start and typically stalls through a gradual decrease in the RPM. It would also run for about 15 minutes but only at about 1K rpm and then stall suddenly with no decrease in RPM. Then it would not start at all. After checking the fuel, replacing the fuel strainer, and bowl gasket I checked compression. Both cylinders have about 130 psi and a bit more when oil is added to the cylinders. When I connect a timing light and the engine stalls the light stops at the same time the flywheel stops. When I remove the prop and put it in a trash can with water I can get the engine to about 5K RPM in gear. When on the lake, I could only get about 1K rpm in gear under power. A boat dealership with a good reputation rebuilt the carb and replaced the fuel line but said they could not fix it without trial and error adding of new parts to see if they could fix it. They would not do that and said I needed a new engine. Another mechanic said I needed to replace the stator and trigger because it was only putting out 1 volt instead of the standard 5 volts. He replaced the stator and trigger (all new). I then took the boat out on the lake, it was difficult to start like before but when I got it going it ran at about 1200-1300 rpm. After about 10 minutes the rpm decreased and it stalled and I could not get it started. Any ideals on what is wrong or how to fix this would be helpful.
