8C-5 Diaphragm Carburetor Adjustment Method - Robin EH09D Service Manual

8c-5 DIAPHRAGM CARBURETOR ADJUSTMENT METHOD

In the first place, set the idle needle !0 !0 !0 !0 !0 and the high-speed needle o o o o o at their standard return openings
and then carry out the adjustment according to the following steps of procedure.
8c-5-1 IDLING ADJUSTMENT
(1) Start the engine and then carry out the adjustment of the idle adjust screw !5 !5 !5 !5 !5 for the engine to operate
at a speed slightly lower than the speed at which the clutch engages.
(2) Turn the idle needle !0 !0 !0 !0 !0 clockwise/counterclockwise so as to find the position where the engine oper-
ates most smoothly.
(3) By means of the idle adjust screw !5 !5 !5 !5 !5 , adjust the engine at a speed approximately 500 r.p.m. higher than
the specified idling speed.
(4) Next, turn the idle needle !0 !0 !0 !0 !0 counterclockwise for the engine to operate at the specified idling speed.
8c-5-2 HIGH-SPEED ADJUSTMENT
(1) Set the throttle valve !6
specified by the manufacturer.
1) If the engine speed is too high, turn the high-speed needle o o o o o counterclockwise so as to adjust the
engine revolution speed at the specified value.
2) If the engine speed is too low, turn the high-speed needle o o o o o clockwise so as to adjust the engine
revolution speed at the specified value.
*The idle needle !0 !0 !0 !0 !0 and the high-speed needle o o o o o are set at the correct adjustments through the execution of
the steps of procedure described above.
At that time, the adjustment is regarded as correct and normal if the needle return opening is within 1/2 of
the standard return opening.
!6 !6 at the fully open state and check whether the engine rotates at the speed !6 !6
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