I bought a 2nd hand Yamaha 4 stroke 4hp specifically for trolling. The problem is that the 5hp 2 stroke it replaced didn't stall that often but this motor will only idle for a minute or so in gear before dying. It rev's it's head off in neutral but in gear it shakes and threatens to stall and eventually does. If I bump the idle up then things are better but it idles way too fast in neutral. The motor came off a tender and didn't get used very often. I only use the internal tank as my main motor is a 2 stroke. I cleaned the tank and fuel filter and it runs fine on the throttle.
