1984 25hp johnson with fuel problem

[Ervin Brumfield]

My 1984 25 hp does not have full throttle I can choke it with my hand and it will run.I have put a complete fuel pump on new fuel lines new bubble and rebuilt the carb I also replaced the arm that the carb flap goes on and reset the rimming. I did a compresson test and I have 100lbs on both clyenders. What's up going crazy

 

[joereeves]

Re: 1984 johnson with fuel problem

If you have compression and proper spark..........

Either the brass high speed jet that's located in the bottom center of the float chamber hasn't been cleaned properly, or the throttle butterfly is not horizontal at the full throttle setting.

 

[Ervin Brumfield]

Re: 1984 johnson with fuel problem

Besides taking out the high speed and washing and blowing out how would you clean the high speed jet

 

[joereeves]

Re: 1984 johnson with fuel problem

I've found that solvent really doesn't do a thorough cleaning, I use a piece of single strand steel wire. However, if you have it out, I'm sure you know if it's clean or not.

If clean, does pumping the fuel primer bulb (acting as a manual fuel pump) make a difference? The small round gasket in place on the vertical nozzle?

At the high rpms, if fuel is in the float chamber, the flow is directly thru the high speed jet and then directly up that vertical nozzle to the venturi.

 

[Ervin Brumfield]

Re: 1984 johnson with fuel problem

What should the compressos on a 25hp 1984 model be

 

[joereeves]

Re: 1984 johnson with fuel problem

Usually 100+ psi and even on all cylinders. What readings do you get?

 

[catangler]

Re: 1984 johnson with fuel problem

Dang Ervin sounds like you have dang near the same problem i have hopefully we can get this resovled

 

[Ervin Brumfield]

Re: 1984 johnson with fuel problem

It is a pull start and by the third pull I have 100 psi on both cly. I don't know what else to do