17 Taking Care of the Guide
Bar
► Turn the guide bar over – every time you
sharpen the chain and every time you replace
the chain – this helps avoid one-sided wear,
especially at the nose and underside of the
bar.
► Regularly clean the oil inlet hole (1), the oil‐
way (2) and the bar groove (3)
► Measure the groove depth – with the scale on
the filing gauge (special accessory) – in the
area used most for cutting
Chain type Chain pitch Minimum
groove
depth
Picco 1/4" P 4.0 mm
Rapid 1/4“ 4.0 mm
Picco 3/8" P 5.0 mm
Rapid 3/8“; 0.325“ 6.0 mm
Rapid 0.404“ 7.0 mm
If groove depth is less than specified:
► Replace the guide bar
The drive link tangs will otherwise scrape along
the bottom of the groove – the cutters and tie
straps will not ride on the bar rails.
18 Cleaning the Air Filter
18.1 If there is a noticeable loss of
engine power
► Turn the twist lock 90° counterclockwise.
► Remove the shroud upwards.
► Remove the air filter upwards.
► Wash the filter in STIHL special cleaner (spe‐
cial accessory) or a clean, non-flammable sol‐
ution (e.g. warm soapy water) and then dry.
NOTICE
Do not use a brush to clean the filter.
Always replace a damaged filter.
19 Adjusting the Carburetor
19.1 General Information
The carburetor comes from the factory with a
standard setting.
This setting provides an optimum fuel-air mixture
under most operating conditions.
19.2 Preparations
► Shut off the engine.
► Check the air filter and clean or replace if nec‐
essary.
► Check the spark arresting screen (not in all
models, country-specific) in the muffler and
clean or replace if necessary.
19.3 Standard Setting
► Turn high speed screw (H) counterclockwise
as far as stop (no more than 3/4 turn).
► Turn the low speed screw (L) clockwise as far
as stop, then turn it back 1/4 turn.
17 Taking Care of the Guide Bar English
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