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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 Operation
This engine has been factory adjusted to maintain satisfactory starting,
emission, and durability performance up to 1,100 feet above sea level
(ASL) (96.0 kPa). To maintain proper engine operation and emission
compliance above 1,100 feet ASL the carburetor
may
need to be ad-
justed by an authorized ECHO service dealer.
IMPORTANT
If the engine is adjusted for operation
above
1,100 feet ASL, the
carburetor must be re-adjusted when operating the engine
below
1,100 feet ASL, otherwise severe engine damage may result.
Exhaust Port Cleaning
Level 2.
Tools required:
Torx T27 L-Wrench, Wood or plastic scraper
Parts Required:
As needed: Heat Shield
1. Remove spark plug lead from spark plug, and remove engine cover
(2 screws).
2. Place piston at top dead center. Remove muffler (A) and heat
shield (B).
3. Use a wood or plastic scraping tool to clean deposits from cylinder
exhaust port.
IMPORTANT
Never use a metal tool to scrape carbon from the exhaust port.
Do not scratch the cylinder or piston when cleaning the exhaust
port. Do not allow carbon particles to enter the cylinder.
4. Inspect heat shield, and replace if damaged.
5. Install heat shield and muffler.
6. Tighten muffler mounting bolts (or nuts) to 80-95 in•lbf
(90-110 kgf•cm).
7. Install engine cover and attach spark plug lead.
8. Start engine, and warm to operating temperature.
9. Stop engine, and re-tighten mounting bolts (or nuts) to specifica
-
tions.
A
B