Thumping when accelerating

[garbubba]

I'm running an old 200hp merc. pretty much the same motor. Can't say that sounds familiar. A spun hub could possible do that but when you go to take off you'll get nothing. Which doesn't sound like the case. I wouldn't think ignition or fuel would be the cause either. It sure sounds like the dog is slipping in the transmission. Which would take us back to the cables. You could disconnect the remote control & try shifting it by hand, that should eliminate a cable issue. Take someone with you & see if you can feel where the thump is coming from, if it's not the top of the motor, it almost has to be in the foot.

Not much help, I know.

Good luck.