49cc troubleshooter


  Adjusting your stock  49cc Mitsubishi single adjustment carburetor for engines with centrifugal clutch.
The trick is to get the engine to accept full throttle while setting still (tire on the ground).
Run the engine until it is hot (five minutes or so) then shut it off.
No Start
Check for leaking fuel, this could be caused by a leaking diaphragm.
Fuel line connected properly  clear line will return fuel to tank
  Turn the air/fuel adjuster clockwise (slotted screw found on the lower left side) until it stops turning. Do not force the adjusting screw.
Next turn the adjuster counter clockwise 2 turns. The engine should start but will not run properly because this is the lean rough setting.
Start the engine and gun it, if it tries to stall turn the air/fuel adjustment counter clockwise ½ turn.

 Try gunning the scooter again, if there is no improvement turn the adjustment clockwise one full turn.

Tweak the adjustment.
 Set the air/fuel adjust to a position that the engine will not stall under full throttle
Set the idle adjustment , just fast enough that the engine will not stall when throttle is released. (Phillips, upper adjustment near throttle body).
 Turn the idle adjust clockwise to speed up or counterclockwise to slow the engine.

FLUTTER: This setting will cause the engine flutter at high RPM, an advanced timing key will ease flutter if you want smooth top end running.


mefast PARTS

334 874 3831

Also see
Performance 49cc carburetor
Throttle Cable