bogging out

[pieman22]

I need help bad. 115 HP V4 1992 Johnson. Ok here goes. Starts up fine, revs up and warms up fine in nuetral. When I give it gas it starts off great and get to 5000 rpms no problem but then about 100 yards it boggs down like its flooded. I rev it up in nuetral,again off we go same thing boggs down when when I accelerate throttle. Please any advice is appreciated,, I want to get at those fish!!!

 

[oldcatamount]

Re: bogging out

Try simple things first...is the fuel tank venting correctly? Any leaks or loose connections in the fuel lines?

 

[pieman22]

Re: bogging out

Checked all the lines and an found no leaks. The primer bulb stays nice and firm through out.

Try simple things first...is the fuel tank venting correctly? Any leaks or loose connections in the fuel lines?

 

[oldcatamount]

Re: bogging out

What you describe is a classic symptom of a tank not venting right. When the motor is begining to really draw some fuel, the lack of air going into the tank will restrict the fuel going out. Although it could be other issues to, I suggest some further testing on the tank. Allow the tank to sit in the sun for a few minutes with the vent open. Then, slowly open the cap, if you hear the sound of air going out, the tanks not venting. Do you have access to a tank that you're sure is venting right? Maybe borrow one from a buddy or a shop. I'm not trying to persuade you here, just trying to eliminate the easy things first and maybe save you some big bucks.

 

[pieman22]

Re: bogging out

good advice thank you very much. I will definetly check it out.

What you describe is a classic symptom of a tank not venting right. When the motor is begining to really draw some fuel, the lack of air going into the tank will restrict the fuel going out. Although it could be other issues to, I suggest some further testing on the tank. Allow the tank to sit in the sun for a few minutes with the vent open. Then, slowly open the cap, if you hear the sound of air going out, the tanks not venting. Do you have access to a tank that you're sure is venting right? Maybe borrow one from a buddy or a shop. I'm not trying to persuade you here, just trying to eliminate the easy things first and maybe save you some big bucks.

 

[James R]

Re: bogging out

With the bulb being firm you most likely have fuel in there. Even so when the motor fades try squeezing the bulb. If the motor picks up you may have a fuel pump problem. Otherwise the carbs need cleaning because you have a needle valve sticking.
I have had problems with insufficient fuel flow giving the same symptoms. Small fuel lines, small bulb. restrictions in the lines. These have been on 1993 150 V6 models and they gave me a warning signal from the vacuum switch on the VRO. Your motor does not appear to have the vacuum switch so no alarm.

 

[stylesabu]

Re: bogging out

if engine came with smaller lines and ran fine at one piont something else has happened. the only needle valve i found in my 75 hp suzuki was for the float. I have found sediment and geled fuel in my carbs and this has cause poor operaation at speeds over 2000 rpm, cleaned carbs and problem was gone.