19
P
OWER
B
LOWER
O
PERATOR
'
S
M
ANUAL
Cylinder Exhaust Port
Level 3.
IMPORTANT
The cylinder exhaust port must be inspected and cleaned of excess
carbon every 3 months or 90 hours of operation in order to maintain
this engine within the emissions durability period. ECHO strongly
recommends that you return your unit to your ECHO dealer for this
important maintenance service.
CARBURETOR
ADJUSTMENT
Engine Break-In
New engines must be operated a minimum duration of two tanks of fuel
break-in before carburetor adjustments can be made. During the break-in
period your engine performance will increase and exhaust emissions will
stabilize. Idle speed can be adjusted as required.
High Altitude Adjustment
High altitude adjustment is not required for proper operation of this
engine.
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.
Before Adjustment
Check that:
• Air filter is clean and properly installed.
• Spark arrestor screen is free of carbon.
• Blower pipes are installed.
1. Start engine, run at idle for one minute.
2. Complete warm up by running at full throttle for 5 minutes, operat-
ing choke twice to clear air from carburetor chambers.
3. Check idle speed and reset if necessary. If a tachometer is available,
idle speed screw (A) should be set to the specifications found on
Page 8 "Specifications" of this manual. Turn idle screw (A)
clockwise to increase idle speed; counter clockwise to decrease idle
speed.
4. Use a tachometer to adjust idle speed to specifications found on
page 9.
A
Summary of Contents for PB-750
Page 22: ...22 NOTES...
