POWER BLOWER
OPERATOR'S MANUAL 21
CARBURETOR ADJUSTMENT - GENERAL
Level 2.
Tools required: Screwdriver, tachometer (Echo P/N 99051130017)
Parts required: none.
NOTE
Do not adjust carburetor unless necessary. If you have difficultly, see your ECHO dealer.
Adjustment Screws
Idle Speed (A) | Control throttle opening at idle. |
Low (LO) Speed (B) Controls amount of fuel at low speed and | |
| supplementary fuel for smooth progression from |
| idle to high speed. |
High (HI) Speed (C) | Controls amount of fuel at full throttle |
Before Adjustment
Check that:
-Air filter is clean and properly installed.
-Spark arrestor screen and exhaust port are free of carbon
-Blower pipes are installed
InitialAdjustment
1.With engine off, turn HI speed screw (C) counterclockwise to stop.
2.Turn LO speed screw (B) midway between stops.
3.Turn idle screw (A) until tip of screw just touches throttle plate; then turn three (3) turns clockwise.
FinalAdjustment
IMPORTANT
Limiter caps prevent exceeding C.A.R.B. and E.P.A. emission limits and over rich adjustment, but not over lean adjustment, which can cause engine failure: Do not exceed recommended HI speed engine R.P.M. during operation, or for long periods during adjustment.
1.Start engine, run at idle for one minute.
2.Complete warm up by running at full throttle for 5 minutes, operating choke twice to clear air from carburetor chambers.
3.Run at idle and accelerate to check for smooth transition from idle to high speed; if engine hesitates, turn LO speed screw (B) counterclockwise 1/8th of a turn at a time until acceleration is smooth.
4.Use a tachometer to adjust idle speed to specifications found on page 11.