1996 40hp johnson dies at full throttle

[johnny1984]

Hey there guys, just bought a new boat today, took it out for a ride an it dies out after about ` km or two at full throttle but will start right back up an run again fine. We were told it could be the fuel line as the bulb is quite soft when he engine is running. Thinkin maybe get the carbs cleaned too. Now... what do you guys think?

 

[johnny1984]

Re: 1996 40hp johnson dies at full throttle

anybody up tonight????

 

[johnny1984]

Re: 1996 40hp johnson dies at full throttle

oh yah i forgot i just bought a new fuel line (the whole thing) so im gonna take it back out an try it tomorow with the fuel lines. another thing. should the lkid of the tank be opened a quarter turn or left fully shut so iut seals?

 

[Rscardina]

Re: 1996 40hp johnson dies at full throttle

Could be the bulb but typicaly it should get soft wehn the negine is running.. what it shouldnt do is collapse on you...if it does then you do have a feul restriction toward the tank..

The high speed jets on your carbs may need some cleaning.. usually if you can start and idle well but have issues at high speed then there is somthing happenng in your carbs.

I think you are on the right track.. clean them up make sure all is free flowing..

 

[Daviet]

Re: 1996 40hp johnson dies at full throttle

The tank cap should be on tight. When you install the new fuel line make sure the fuel flow is going the correct direction. You might try squeezing the primer bulb when it acts up and see if it runs better, if so you might have a fuel pump problem, or air getting into the system someplace. The primer bulb will not be hard with the engine running.

 

[Rick.]

Re: 1996 40hp johnson dies at full throttle

Sudden death is a clue here. A fuel restriction will cause it to bog and air leak will cause it to hunt/sputter but sudden death is what your getting followed by it starting right back up. Are you venting your tank in other ways than opening your fuel cap? Is your kill switch lanyard getting bumped? I really don't have a solution but I wouldn't pull the carbs. apart just yet. Is it a two cylinder? I have a 95 - 40 hp. Best of luck. Rick.

 

[johnny1984]

Re: 1996 40hp johnson dies at full throttle

no we are not venting the tank in any way. we are fairly new to bigger boats (had plenty of 15s) this is a twin cylinder, twin carb, electric start model. the killswitch lanyard could be getting bumped... do you have any ideas anyone?

 

[Rick.]

Re: 1996 40hp johnson dies at full throttle

So what kind of tank are you using. If it is a portable tank you have to vent it. There should be a way unless your using an original OMC tank that vents as soon as you connect the hose. No matter I would give it a try with the gas gap loosened off just to see if that's the problem. Rick.

 

[johnny1984]

Re: 1996 40hp johnson dies at full throttle

the tank had quite alot of pressure built up in it. it let go a good burp when i removed the lid. also when i took the hose off it ****in sprayed me right in the eyes with fuel... stupid me i know... lol. were gonna go out tomorow an test it out an will report back.