9.9 Yamaha 4 stroke fuel problem

[mcgyver]

My 1996 little engine quit this weekend. Definitely a starved for fuel problem. When I pump the bulb the bulb does not get hard and i can't feel fuel flowing through it. when i disconnect from the motor connector and press in the bearing and then pump the bulb I get fuel. reconnected everthing and disconnected the hose right before the fuel pump and got flow, reconnected and pulled the hose right after the fuel pump and get flow. connect everything up and pump the bulb and simular to the roiginal problem, basically a dry bulb. Where do i go from here? thanks BTW the fuel is coming from a racor filter separator and seems intact.

 

[mcgyver]

Re: 9.9 Yamaha 4 stroke fuel problem

here's the update. when i hold the bulb vertical it gets hard and everything normal. Disconnected the hose as it enters the carb and turned over the motor and got fuel, now know that fuel is making it to the carb as usual. checked spark at plugs and that is strong. engine will not cough or anything with fuel getting to carb therefore something IN the carb is faulty...where do i go from here. And believe it or not this weekend is the big 3 night fishing trip to the west coast of vancouver island!!!! murphy's law strikes again. Help me get this thing fixed before that....thanks

 

[mcgyver]

Re: 9.9 Yamaha 4 stroke fuel problem

another update....engine will run with moving the throttle linkage to keep it running but stalls at idle. have removed the pilot jet and sprayed carb cleaner into the hole. no change. I'm stumped....... the engine ran great last weekend......

 

[mcgyver]

Re: 9.9 Yamaha 4 stroke fuel problem

I've got the carb pulled apart and will pick up a rebuild kit in the AM. Lots of gunk in the bowl. Anyone suspect a certain part of the carb that would have caused these symptoms?

 

[sdsaw]

Re: 9.9 Yamaha 4 stroke fuel problem

It appears that you are answering all your own questions

...I suspect a clogged jet.
I have an older model, but unscrew the main jet to access the pilot jet.
Pay attention to which way the flats are facing(pilot jet)for reassembly.
Carefully clean all passageways.
You might be able to get away without a rebuild kit if you don't tear any of the gaskets.

Good luck mcgyver
With a name like that, it should be a piece of cake!

 

[mcgyver]

Re: 9.9 Yamaha 4 stroke fuel problem

Soaked all metal parts in carb cleaner overnight. Lunch time blew everything out, reassembled, re-installed (took maybe....1/2 hour start to finish) no rebuild kit, fired her up and she runs better than has in the past year....puuuuurrrrsssss..like a kitten...I'm one happy guy and saved the trip this weekend.... Thanks