Echo HCA-2500 - Manual (Page 9)

SERVICE INFORMATION HCA-2500
9
2-3 Adjusting carburettor
1. Start engine and warm it up alternating engine
speed between WOT and idle every 5 seconds for
1 minute.
2. Using 2.5 mm wide blade screw driver, adjust L
mixture needle to obtain maximum idle speed.
3. Set idle speed in the range of 3,400 to 3,500
r/min by turning idle adjust screw.
4. Turn L mixture needle anticlockwise to reduce
engine idle speed 700 to 800 r/min to set idle speed
in the range of 2,600 to 2,800 r/min.
NOTE : Engine speed must be allowed to stabilize
a minimum of 20 seconds after each adjustment of
L mixture needle to assure accurate tachometer
readings.
5. Turn H mixture needle anticlockwise to reduce
engine speed to approx. 9,000 r/min at WOT.
6. Turn H mixture needle clockwise to obtain 9,500
to 10,500 r/min at WOT.
NOTE : During H mixture needle adjustment, do not
run engine at high speed without load longer than
10 seconds.
7. If the engine speed at WOT is above 10,500
r/min, adjust H mixture needle anticlockwise and set
maximum engine speed at less than 10,500 r/min.
idle adjust screw
(Continued)