I have what I believe is an '06 Yamaha four stroke outboard and I also have an '05 Mercury four stroke big foot outboard. They are identical to my eye, in every detail so far except one: the accelerator pump in the Yamaha is disabled and the Mercury is fully functional. The carbs are identical.
'They' disabled the accelerator pump is disabled in the Yamaha by means of a welch plug located in the top of the carb bowl that prevents the output of the accel pump from traveling through the passages and to the little tube with a hole in it that squirts raw fuel into the intake stream.
All of the accel pump components are present in the Yamaha, the sole difference that I see is that obstructing welch plug.
While I have the carb apart (the Yam was in storage for several years and I wanna clean the carb) I'm thinking about drilling a modest sized hole in the welch plug to enable the accel pump. I've never run the yam, tho I will soon, but am most unenthusiastic about any stumble on acceleleration.
So to drill the welch plug or not. that is the question.
?
'They' disabled the accelerator pump is disabled in the Yamaha by means of a welch plug located in the top of the carb bowl that prevents the output of the accel pump from traveling through the passages and to the little tube with a hole in it that squirts raw fuel into the intake stream.
All of the accel pump components are present in the Yamaha, the sole difference that I see is that obstructing welch plug.
While I have the carb apart (the Yam was in storage for several years and I wanna clean the carb) I'm thinking about drilling a modest sized hole in the welch plug to enable the accel pump. I've never run the yam, tho I will soon, but am most unenthusiastic about any stumble on acceleleration.
So to drill the welch plug or not. that is the question.
?
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