Guide :Sport & Outdoor - Others : Sport & Outdoor - Others
Engine runs rough when we throttle up
We have a 40hp 2 stroke Yamaha engine on our boat. It ran great then it started to run rough when we would increase the throttle. It was intermittent at first, now it is all the time. We changed the plugs, new gas filter,carburtor was taken off cleaned and adjusted . It worked great for about 20 minutes then we shut down and anchored. When we were off on our way again it started all over. Could this be an electrical problem.