lower carb float valve foulup

[SCO]

Yamaha 2005 50 hp 2 stroke.
Had been taking it out about once monthly. The last time, it ran great for 30 seconds then lost a cylinder. Idling would recharge it for another go round. I found the lowest carb float valve stuck, the other two brand new clean. I was letting the motor run the bowls dry, I thought, but whatever was left probably left the lowest bowl full since the three carb fuel supply lines are ganged together. The fuel had some premix oil in it though this is an injection model(injected after the carb). Maybe that premix oil fouled the carb. From now on I am just shutting the motor off leaving the carbs full of fuel and not premixing. I think my procedure was building varnish every time I ran the motor and put it away.

Am I on or off track?

 

[Ray Neudecker]

Re: lower carb float valve foulup

One of the big advantages of the oil injection on a Yamaha is that oil does not go through the carb. I reccomend draining if you are going to put it up.

 

[Ray Neudecker]

Re: lower carb float valve foulup

One of the big advantages of the oil injection on a Yamaha is that oil does not go through the carb. I reccomend draining if you are going to put it up.

 

[JUSTINTIME]

Re: lower carb float valve foulup

read the owners manual, it will say what to do

 

[SCO]

Re: lower carb float valve foulup

It says to just turn it off and stabilize fuel if putting up. It also says to use un mixed fuel after break in. So yes, when all else fails, read the manual.

 

[JUSTINTIME]

Re: lower carb float valve foulup

see, some manuals says drain it, some says stabilize, some say just leave it

 

[SCO]

Re: lower carb float valve foulup

I was thinking of draining all the carb bowls every time, but if I do that, the film of fuel will dry out every time I take the boat out. Maybe the varnish would build up like scale on a water faucet.
I'm just glad to be able to add some info to the "should I disconnect the fuel line and let the engine die " debate. It's a definite no for the Yamaha stacked carb config like my engine!