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Cylinder fins (Cooling system)
Check periodically.
Clogged fins will result in poor engine cooling.
Remove dirt and dust from between fins to let cooling air pass easily.
Guide bar
Clean before using.
- Clean the groove of the guide bar with a small screw driver, for example.
- Clean oil holes with a wire.
Reverse guide bar periodically.
Check sprocket and the clutch and clean the bar mount area before installation of the guide
bar.
Replace either or both if worn.
Sprocket
∗
Worn out: 0.5 mm
The damaged sprocket will cause premature damage or wear of saw chain.
- When the sprocket has worn out 0.5 mm or more, replace it.
Check sprocket when you install new chain.
Replace it if worn.
Carburettor
L: Low speed mixture adjuster
H: High speed mixture adjuster
T: Idle speed adjuster
Do not adjust the carburettor unless necessary.
To adjust the carburettor proceed as follows:
- Turn screws in the needles (L and H) clockwise until lightly seated and return as
indicated below.
- Low speed mixture adjuster (L): 1 and 1/4 to 3/4 turns open.
- High speed mixture adjuster (H): 1 and 1/4 to 3/4 turns open.
- Turn idle speed adjuster (T) clockwise until chain begins to rotate.
Then back screw 1/2 turn.
- Accelerate to full throttle to check for smooth transition from idle to full throttle.
Automatic oiler
The discharge volume of the automatic oiler is adjusted to 7 mL/min approximately at
7000 r/min, prior to shipment from factory.
- To increase the delivery volume, turn the adjusting screw anticlockwise.
When the adjusting screw touches stopper and stops, this position indicates maximum
discharge volume. (13 mL/min at 7000 r/min)
- Do not turn the adjusting screw beyond the maximum or minimum limit of volume
adjustment.
NOTE
When replacing guide bar or saw chain, ask your ECHO dealer.
1. Groove
2. Oil
hole
3. Guide
bar
4. Sprocket
CAUTION
When starting, idle speed adjuster (T) should be adjusted not to rotate the saw chain.
When there is some trouble with the carburettor, contact your dealer.
1. Oil
adjusting
screw
2. Decrease
3. Increase