Soup up my 1976 40hp Evinrude

Howdy, a new guy here. It's nice to see a forum so full of outboard enthusiast.
I recently bought a 1976 40hp evinrude and finally got it fired up and running fairly well, however, it does not seem to top out like it should. When running WOT, it will slightly hesitate and will actually run stronger when I back off just slightly. The motor has 120 psi on both cylinders and starts and runs good, but I just feel like it should have more punch. It just doesn't tack out like it should. I have it on a 13 ft Boston Whaler and it should make this boat fly. Also, it does not idel all that great. I have not adjusted anything on the carb yet. Would rebuilding the carb be a good idea for the cure? What else might you suggest I do to get better performance out of this motor.

Thanks for your time!
Danny

Re: Soup up my 40 Evinrude

I would clean the carbs really good making sure to clean the jets and putting in carb kits. Sounds like the motor has been sitting awhile.

Re: Soup up my 40 Evinrude

I'm not sure about the history of the motor. The guy I bought it off of never even had it on a boat. It probably has been a while since it has ran. I managed to burn about 3 gallons of fuel through it today and it never did "blow itself" out. I did put some high grade carb cleaner in the fuel mix and I'll probably do it again tomorrow. The motor runs great from 1/4 to 3/4 throttle so I can't complain, I just want it to top out better.

Re: Soup up my 40 Evinrude

Had a similar problem with my '89 40hp Johnson.Removed cowling to access fuel filter and tapped intake side of filter out on a piece of paper towelling to find bits of grime had caused a restriction.In my case I simply had not taken the time to clean out the old cruise-a-day that had been sitting for some time.Easiest place to start.