OK, I am not a professional outboard mechanic or come close to it. I have messed around with them a bit though. This one has me really stumped. I have a mid 80s Johnson 48 2 cycl 2 carb motor. The motor seems to surge and sometimes stalls at low rpm (under load only). I thought it could be a fuel pump or low speed jet problem so I replace the entire fuel pump and rebuilt the carbs with kits. This produced no better results. After running it on the ears and watching the carbs a bit, I notice that the top carb was spitting out fuel mist at idle and low rpm. I noticed that the bottom carb sucked in air much more than the top one did. I did not try it at high rpm because it was on the ears. No problem I said, I must have messed something up in the top carb. Before tearing the carb down again, I decided to swap the carbs and run it again. This produced the SAME spitting in the top carb indicating that it was not the carb. Well now I though that the top cylinder was shot, but I did a compression check and they both read about 128lbs. Ok next, I tried putting in new plugs, swapping the plug wires and the coils, all with the same results. I also tried it with the throttles and choke hoses disconnected. I dont know what else to try. Could this be a reed valve problem? I have never seen a problem with the reed valves, and dont really want to tear into it if not needed. The motor does not have many hours on it. The model number is J48ESLCER and the SN is G 02346356.
