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BT 121
English
20
Maintenance and Care
The following intervals apply to normal operating conditions only. If your daily work-
ing time is longer or operating conditions are difficult (very dusty work area, etc.),
shorten the specified intervals accordingly.
be
for
e st
art
in
g w
o
rk
af
ter fi
ni
sh
ing w
ork or dai
ly
af
ter eac
h
re
fue
ling stop
we
e
kly
mo
nth
ly
eve
ry 12
m
on
ths
if p
ro
b
le
m
if d
am
age
d
if r
eq
u
ire
d
Complete machine
Visual inspection (condition, leaks)
X
X
Clean
X
Auger brake
Check operation
X
X
Have serviced by dealer
1)
X
Control handle
Check operation
X
X
Air filter
Clean
X
Replace
X
Pickup body in fuel tank
Check
X
Replace
X
X
Fuel tank
Clean
X
Carburetor
Check idle adjustment – drilling spindle
must not rotate
X
Readjust idle
X
Spark plug
Readjust electrode gap
X
Replace after every 100 operating hours
Spark arrestor
2)
in muffler
Have checked by dealer
1)
X
Have cleaned or replaced by servicing
dealer
1)
X
X
All accessible screws and nuts (not adjust-
ing screws)
Retighten
X
Antivibration elements
Check
X
X
X
Have replaced by dealer
1)
X
Gearbox
Re-lubricate
X