Anti Siphon valve cause of Full Throttle Cut off ?

[bobafett]

I have a previously posted my problems with my 1986 Merc 140 hp bogging/ cutting off only on going from idle to full throttle. Already rebuilt carb. I went to a boat service business today and the mechanic said that it could be a dirty or clogged Anti-siphon valve connected at the tank and probably not the fuel pump. Is that a possible cause? I can get up to high RPM/speed if I slowly inc. the throttle, but not as if pulling up a skier. This troubleshooting is esp. frustrating and my summer is going by too fast. All the service guys in town say they are backed up 3 weeks before they can look at it! Any other ideas to problem solve would be great! You guys are Awesome!

 

[RubberFrog]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

Could be.

 

[jeff13601]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

I would check the screen on the fuel pick up line that is on the bottom of the tank. Also make sure the vent to the tank is clear. It could also be the anti syphone valve

 

[bobafett]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

The screen, is it the filter right before the carb inlet or is it between the fuel pump and tank?

 

[RubberFrog]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

Originally posted by bobafett:<br /> The screen, is it the filter right before the carb inlet or is it between the fuel pump and tank?

"screen on the fuel pick up line that is on the bottom of the tank"<br />I would also check the filter on the carb inlet. Do you have a fuel/water separator?

 

[bobafett]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

No water separator How much does it cost and how/where does it mount?

 

[jeff13601]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

The screen I am talking about is in the bottom of the gas take at the end of the line the gas comes through

 

[rodbolt]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

a ten minute session with a vacum gauge will tell you if the tank,lines or anti-siphon valve is clogged. its quick, its easy and reqires no guessing.

 

[pine island fred]

Re: Anti Siphon valve cause of Full Throttle Cut off ?

If there is no screen at the bottom of the fuel pick up tube, it is probably inside the tube. finger filter. Remove the tube then remove the fitting at the top, push the screen out from the bottom. regards fred