Fuel Line; Tank Vent - Stihl 009 User Manual

STIHL 009, 010, 011
8.7

Fuel Line

Withdrawing the pickup body
The diaphragm pump draws fuel out
of the fuel tank and into the carburetor
via the fuel line. Any impurities mixed
with the fuel in the tank are filtered out
by the pickup body (filter and felt bar).
The fine pores of the felt bar
eventually become blocked with
minute particles of dirt. This restricts
the passage of fuel and the result is
fuel starvation.
In the event of trouble with the fuel
supply system, always clean the filter
in the pickup body first. To do this,
pull the pickup body out through the
tank filler.
The felt bar can now be taken out of
the pickup body and replaced. When
reinstalling the pickup body, make
sure it is positioned at the lowest point
in the tank.
It is not advisable to clean the felt bar
- always fit a new one.
Removing the felt bar
Trouble-free operation of the
carburetor depends on the fuel tank
and atmospheric pressures always
being equal. This is assured by the
8.8

Tank Vent

Tank vent in position
The tank vent consists of a tube and a
grub screw. When replacing the tank
vent, push grub screw into the tube,
slotted end first, until its tip is flush
with the end of the tube.
Then insert tube about 8 mm in its
housing bore with the tip of the grub
screw facing the carburetor chamber.
In the event of difficulties with the
carburetor or fuel supply system,
always check and clean the tank vent.
If the thread of the grub screw has cut
deeply into the tube, replace the vent
tube.
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