18
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
Every unit is run at the factory and the carburetor is set in compli-
ance with emission regulations. This carburetor does not have
acceleration and high speed adjustment needles.
Idle Adjustment
Before adjustment make sure 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,
operating 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 21 "Specifications" of this manual. Turn idle screw
(A) clockwise to increase idle speed; counter clockwise to
decrease idle speed.
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.
A
Summary of Contents for PB-251
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