1994 johnson 25 hp

kevin11mic

Petty Officer 3rd Class
Joined
Oct 12, 2010
Messages
96
I have this motor on a 14ft deep and wide with a side console. It has a 10x13 prop on it. The motor dosent seem to be running at its full potential. When accelerating to wot it wind of sputters then goes and it takes a little while to get on plane. once on plane and i make a turn like when running through a bendy cut it bogs down. What are the factory carb setting on the adjustment screw and what else could i do to get more power
 

jbjennings

Captain
Joined
Jul 18, 2007
Messages
3,903
Re: 1994 johnson 25 hp

I would take the carb apart and clean all tiny passages. Your carb has a fixed high speed jet and since that's when you're having problems, there is no way to adjust it other than cleaning it out really well. I wouldn't remove the jet if I were you since it is doubtful you have the right tool. Just run a piece of thin copper wire through the jet and blow it out good with carb cleaner and compressed air. Put it back together, being EXTREMELY careful not to break off any plastic hose nipples, and see what happens. Also check your tank vent and fuel lines, and maybe try pumping the primer bulb at high speed and see if it picks up. If so, suspect clogged fuel filter or possibly weak fuel pump.
GOod luck,
JBJ
 

kevin11mic

Petty Officer 3rd Class
Joined
Oct 12, 2010
Messages
96
Re: 1994 johnson 25 hp

well when at wot i could push the choke in and it would pick up rpm's
 

kevin11mic

Petty Officer 3rd Class
Joined
Oct 12, 2010
Messages
96
Re: 1994 johnson 25 hp

Also is there supposed to be some kind of silencer or something for the air flow on the carb because right know there isnt anything on it, you can see straight through the carb. So if there is suposed to be something on it it might be getting to much air
 

jbjennings

Captain
Joined
Jul 18, 2007
Messages
3,903
Re: 1994 johnson 25 hp

well when at wot i could push the choke in and it would pick up rpm's

That is probably the most classic symptom there is for a motor that needs it's carb cleaned. If you continue to run it that way (LEAN), it is likey that you will ruin it. Clean the carb and problem solved, most likely. There is no silencer on that motor as far as I know. It should be as you describe.
Good luck,
JBJ
 

kevin11mic

Petty Officer 3rd Class
Joined
Oct 12, 2010
Messages
96
Re: 1994 johnson 25 hp

ok thanks for the help...ill pull it off and clean it
 

78 mckee

Seaman
Joined
Feb 9, 2009
Messages
59
Re: 1994 johnson 25 hp

I have several motors like yours on my boats. They are great motors. There could be a problem with the carb, and I would check that first. But if that doesn't do the trick, I would change the prop. I run a 10 1/2 x 11 on my 14ft McKee and 11 x 9 on my 16ft Lowe with these motors. They get up on plane in seconds and run between 25 and 30 MPH. The 10 x13 may be too deep a pitch for heavy boats with a 25hp, that may be why it SEEMS to bog in a turn; there is more drag on the hull in a turn than running straight. Also, if the pitch is too deep it will take longer to get it on plane and you'll need calmer water to get it there. Good luck. Great Motors, I love 'em.
 

kevin11mic

Petty Officer 3rd Class
Joined
Oct 12, 2010
Messages
96
Re: 1994 johnson 25 hp

I rebuilt the carb and removed the oversize whale tale that the guy before me put on it that was just causing drag. the boat runs great...had three people and fishing gear and was running 25mph with lots of power. with the weight situiated right it would jump on plane in no time...thanks for the help
 
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