1990 115 mariner- major fuel issue

[cobia186]

I have a 1990 merc mariner 115. the carbs were just gone thru. But the problem I am having now is this- The 2nd carb from the top of the engine is pouring fuel. When I squeeze the primer bulb, fuel shoots out from behind the carb in the intake somewhere. So I pulled the carb off, and while squeezing the bulb, I was able to see a lot of fuel squirting in the intake. Any ideas???-- Also, while the engine is running, gas is pouring out from the same spot behind the carb.

 

[cobia186]

Re: 1990 115 mariner- major fuel issue

Update- Put everything back together. I started the engine, and same problem- gas is pouring out of the 2nd carb from the top!!! Is there some sort of check valve that could be bad allowing pressure to build up in the fuel system??? I have a cheaper manual- and it seriously lacks in areas. I really need some good sound advice on this 1990? engine. The serial number tag is long gone- but from what the local boat mechanic said, he "thinks" its a 1990 model. Just found a plug with the following serial # OG127522 or O6127522 hard to tell if the 2nd digit is a "G" or a "6". If anyone knows the year of this engine I would appreciate it.

 

[cobia186]

Re: 1990 115 mariner- major fuel issue

ok- here is what I have narrowed down. My primer bulb is not building pressure. It is pumping fuel into a fuel line which T's off of the furl line between the top 2 carbs. The line then goes from the T to a valve looking item mounted on a bracket. From there, the line goes over to the other side of the carbs and splits via another T. From that T it goes into the engine via 2 nipples that are located on the intake manifold right behind the carbs. I will try to attach pics.

 

[cobia186]

Re: 1990 115 mariner- major fuel issue

Update- The choke enrichment valve was stuck open- problem solved.

 

[1979checkmate]

Re: 1990 115 mariner- major fuel issue

bad float valve or float sounds like.