by Larry McGrath
I have a 1998 Johnson 25hp 3 cylinder that is not running right. Every time I start it up it will run fine for a few seconds and then start bogging down like its a fuel issue. I have changed spark plugs, cleaned all carbs, made sure all carbs were getting fuel, by the fuel pumps and straight from the tank by connecting the hose to the fuel rail from the tank and constantly priming the bulb but the issue still continues. All spark plugs have fire. So the question is, Is it possible that the power pack or the coil packs are failing after it runs for a few seconds? Also I noticed when I first got the motor someone had dug into one of the carbs and attempted to replace the welch plug and ended up leaving a whole in it which in turn kept flooding that cylinder. that did give me the same problems im having now but I fixed it with jb weld but after a year I noticed it got the same problems again which is where im at now. A week ago I did put some new fuel resistant permitech goo on it put it back together and did the same thing. I pulled the carb back apart and noticed, that stuff became diluted and probably got sucked up in the hole on the welch plug. so since I knew jb weld fixed it the first time but didn't last long I did it again. but this time I still have the same problems. Is it possible that some of that gunk got under neath that welch plug and is starving that one cylinder for fuel. I can start it give it gas a few times then it falls on its face. I can wait a minute start it again runs fine for a few seconds and falls again over and over and over. Anybody with this same issue or any ideas please help this is starting to get frustrating.
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