Yamaha 50HP 4-stroke Carb

[inter911]

My engine was running poor so I took it to a local marine place. They said the four carbs needed to be rebuilt so they rebuilt them and I paid a little over $600 for the work. the engine runs a bit better but still not right. They claim that one of the carbs did not respond to being rebuilt and that it needs to be replaced but there is none to be found anywhere. The problems started when I filled the tank with fuel from a place that I found out after is known locally to have poor fuel quality. Tank has been flushed, new gas, carb cleaner/fuel conditioner added, carbs rebuilt…still carb on cylinder 3 does not seem to be delivering fuel to the cylinder. There's fuel in the bowl and when you spray a little fuel into the vacuum hole the engine picks right up. Disconnect spark plug lead on #3 and no effect on engine, disconnect on any other cylinder and immediate effect on engine.

Any thoughts on what to check? Thoughts on "no carb available anywhere"? Does it make sense that a carb cannot be rebuilt? This engine has very little use on it. Used a few times each summer only.

 

[boscoe99]

How is anyone to respond to your questions with any meaningful answers without knowing the model of your motor?

Do you go to NAPA and just say give me some plugs for my truck without telling them what kind of truck that you have? If you don't care what kind of plugs you get that might work. Same with an outboard motor.

Yamaha first offered an F50 in 1995. An F50TLRT. The carburetor for that specific model is still available today. Who is telling you that a replacement new carburetor is not available?

Yes, a carburetor can get so much junk inside that it cannot be removed. The carburetor is then toast. However, some folks don't really know how to clean carburetors.

 

[Georgesalmon]

I have one of those first '95 Yamaha 50's. There is a problem with the carb's that cannot be rebuilt. Something about a seat that is machined in and not replaceable. However, I was told I can still get new carbs if needed but they cost a fortune. I was lucky, Mine were OK after being rebuilt as much as possible.