Hard to plane under load


New member
I have a 60/45 mercury jet. It wasn’t run for about 4 years. I had a few issues with it. Biggest was the carbs needed rebuilt. After rebuilding the carbs and cleaning out the fuel and replacing all the filters the boat ran excellent. All of a sudden now the boat won’t plane when I have a friend with me. When I am alone the boat runs fine. Accelerates just fine and planes. But with my buddy it won’t. This has got me so confused because it ran fine now all of a sudden won’t. It was bucking for a bit and I replaced the rpm regulator and that solved that issue but it still has an issue. Now if I take off super slow and go down river it will eventually plane and when it planes it runs fine. I’m at a lose and just don’t know what the issue could be. Any suggestions?


New member
did you rebuild the fuel pump when you serviced the carbs?
Yes I did. The funny thing is it ran great. Then all of a sudden it started bucking. So I replaced the rpm regulator and now it’s like it doesn’t have the umf to get up. The rpms seem to go up but the power doesn’t.


Silver Medal Contributor
can you try another tank to isolate the existing tank as a cause...same for the fuel line?

I could be that you initial overhaul actions did what they were intended to do but the use afterwards caused something to change....maybe loosened some crud in the tank or something in the fuel line restricting flow??