Problem with acceleration - 25hp

peedeeboater

Cadet
Joined
Jul 18, 2004
Messages
6
I have a Johnson 25hp, 1992. It idles and revs fine with the muffs. When in the water, it dies when I give it the gas. Seems like it is flooding or starving. Thus far I have: Changed plugs, cleaned carb (it was my first and I "think" I did it well), float is parallel when carb upside down. Cleaned the fuel pump. It cranks with either plug disconnected. Have changed oil in lower case; it was kind of dark, but not too bad. New gas, and bulb & line only 1 year old. Pumping the bulb makes no difference. It ran fine the last time I used it (last year). Oh yeah, occasionally, it will surge before it dies. Any ideas???
 

buckbass

Recruit
Joined
Jul 19, 2004
Messages
2
Re: Problem with acceleration - 25hp

I wish I could help I am having the same problem with my 1985 johnson 30hp.<br />Someone said to check the high speed jet but don't know if this small of an egine has one.
 

OBJ

Supreme Mariner
Joined
Dec 27, 2002
Messages
10,161
Re: Problem with acceleration - 25hp

Sounds like it's running a little rich peedee. The surge before it dies gives it away.<br /><br />When you rebuilt the carb, did you remove the low end idle screw? If so, turn it in one or two turns and see if that helps. Always make your adjustments on the water. The water makes the backpressure against the cylinders so you can adjust the carb correctly. Running on muffs does not create back pressure.<br /><br />Once you get the engine to idle, run it till normal temp is reached and fine tune the needle while in gear.<br /><br />Keep us posted.
 

max4owner

Cadet
Joined
May 24, 2003
Messages
20
Re: Problem with acceleration - 25hp

Hi -<br /><br />I had this problem. If you look at the timer base, it may not be advancing the timing because the spring is weak or the electrical cables are stiff. My electrical cables were stiff. I ended up putting a helper spring on the timer plate.
 
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