The problem you have isn't a problem. You are over reving the crap out of that motor. It's an RV motor not a race motor. It isn't designed to rev that high.
Normally would never. I just did it whenit started bucking and popping back .so there is probably nothing wrong with it at this point and whatever was causing it to buck on the highway, I might have cured.
I think I'm gonna putthe trailer back on it and load my skid steer and take it for a run down the highwY and pull a hill or too.
If she runs ok , I'll call it fixed.
