I have a 1981 Johnson 25 HP outboard, model J25RWCIM.
I bought it in rough shape last summer, rebuilt the carb, water pump, fuel pump, fuel lines, ignition, etc. etc. - and got it running like a champ.
I had fun running it around last summer, fogged it, drained it, and put it away for the winter.
This spring I got it started right up again (2 pulls!) and had a nice fishing trip with it a few weeks ago - everything worked just fine.....Until.....
I had it out again this week, and it was running fine - a buddy and I went to a couple of different fishing spots, and were heading downriiver to another. Motor was running great. The boat was up on plane (14' Starcraft seafarer) and I was cruising at about 80% throttle. And then out of nowhere it died very suddenly. It was like somebody hit the kill switch.
It wouldn't start or run unless I choked it, and even when choked, anything over about 30% throttle would kill it. But it would start right up on choke and run (roughly) So I limped it back to the dock, which fortunately wasn't too far away. Pumping the fuel line primer bulb has no effect, so I don't think it's a blown diaphragm in the fuel pump.
Sounds like a carb issue, right? Maybe I sucked up some largish piece of debris or blew out a seal allowing too much air in. It just seems strange that it would happen so suddenly and after the motor had been running just fine a week or so ago, but I guess it's possible. The way that it died so suddenly, I would suspect an ignition problem - but the fact that it manages to fire on choke kinda shoots down that theory.
I'm gonna tear into it this weekend - any other ideas of where I should look for the problem?
I bought it in rough shape last summer, rebuilt the carb, water pump, fuel pump, fuel lines, ignition, etc. etc. - and got it running like a champ.
I had fun running it around last summer, fogged it, drained it, and put it away for the winter.
This spring I got it started right up again (2 pulls!) and had a nice fishing trip with it a few weeks ago - everything worked just fine.....Until.....
I had it out again this week, and it was running fine - a buddy and I went to a couple of different fishing spots, and were heading downriiver to another. Motor was running great. The boat was up on plane (14' Starcraft seafarer) and I was cruising at about 80% throttle. And then out of nowhere it died very suddenly. It was like somebody hit the kill switch.
It wouldn't start or run unless I choked it, and even when choked, anything over about 30% throttle would kill it. But it would start right up on choke and run (roughly) So I limped it back to the dock, which fortunately wasn't too far away. Pumping the fuel line primer bulb has no effect, so I don't think it's a blown diaphragm in the fuel pump.
Sounds like a carb issue, right? Maybe I sucked up some largish piece of debris or blew out a seal allowing too much air in. It just seems strange that it would happen so suddenly and after the motor had been running just fine a week or so ago, but I guess it's possible. The way that it died so suddenly, I would suspect an ignition problem - but the fact that it manages to fire on choke kinda shoots down that theory.
I'm gonna tear into it this weekend - any other ideas of where I should look for the problem?
