![background image](http://html1.mh-extra.com/html/echo/pb-413h-02-09/pb-413h-02-09_operators-manual_4077188023.webp)
23
P
OWER
B
LOWER
O
PERATOR
'
S
M
ANUAL
A
B
C
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 mean sea level
(MSL) (96.0 kPa and below). To maintain proper engine operation and
emission compliance above 1,100 feet MSL the carburetor may need
to be adjusted by an authorized ECHO service dealer.
IMPORTANT
If the engine is adjusted for operation
above
1,100 feet MSL, the
carburetor must be re-adjusted when operating the engine
below
1,100 feet MSL, otherwise severe engine damage can result.
Exhaust Port Cleaning
Level 2.
Tools required:
4 & 5 mm Hexagon wrench, Cross head
screwdriver, Wood or plastic scraper
Parts Required:
As needed: Heat Shield
1. Remove spark plug lead from spark plug, and remove engine or
muffler cover (5 screws).
2. Place piston at top dead center. Remove muffler (A) gasket (B),
and heat shield (C).
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 (C) and gasket (B) and replace if damaged.
5. Install heat shield (C), gasket (B), and muffler (A).
6. Tighten muffler mounting bolts (or nuts) to 105-150 in•lbf
(120-170 kgf•cm).
7. Install engine cover.
8. Attach spark plug lead.
9. Start engine, and warm to operating temperature.
10. Stop engine, and re-tighten mounting bolts (or nuts) to specifica-
tions.