1996 evinrude hunting at 3/4 throttle

[eddietrx]

I have a 1996 25HP Evinrude model no. HJ25FPO and it runs fine except at about 3/4 throttle when it hunts badly and revs pick up and drop by 300-500 rpm other than that it runs smooth through the rest of the operating RPM.

 

[eddietrx]

Re: 1996 evinrude hunting at 3/4 throttle

Has anyone come across this?

 

[mtlurz]

Re: 1996 evinrude hunting at 3/4 throttle

I'm having the same problem on my 1996 50hp Evinrude. Starts fine, runs great to about 1/2 throttle and above where it will bog down, rev up, bog down.....continuously. I rebuilt the carbs, checked all fuel lines, rebuilt the fuel pump, changed plugs and checked all electrical connections and still have the same problem. Maybe someone can help us out here.

 

[Silvertip]

Re: 1996 evinrude hunting at 3/4 throttle

That problem is almost always fuel related and is typically narrowed down to two causes. 1) weak fuel pump or 2) a restriction in the fuel system (pickup in the tank, clogged vent, bad primer bulb, air leak in lines etc). On portable tanks, empty the tank and check the inside very carefully for bits of plastic debris left over from the manufacturing process. I've seen these bits in a number of cases including my own boat as well as new tanks at various stores. They clog the intake dip tube. When the engine begins to bog/surge, try squeezing the primer bulb. If that helps you have verified the restriction/fuel pump issue. If that doesn't help, go for the carbs. Those idle and high speed passages and jets need to be squeaky clean.

 

[mtlurz]

Re: 1996 evinrude hunting at 3/4 throttle

Thanks for takin the time to post some tips and will try them once I have the time and will post results! Hope eddietrx finds them useful as well.

 

[mtlurz]

Re: 1996 evinrude hunting at 3/4 throttle

Rebuilt the fuel pump and back in business!!!! Thanks silvertip! I love my boat again.....