
GB-13
G
B
BT251
9. Maintenance
Every Every Every
25
50
100
System/components
Procedure
Before
hours hours hours Note
use
after
after
after
fuel leaks, fuel spillage
wipe out
✔
fuel tank, air filter, fuel filter
inspect/clean
✔
✔
replace, if necessary
see adjusting
replace carburetor
idle adjusting screw
✔
idling speed
if necessary
clean and readjust
GAP: 0.6 ~ 0.7 mm (.025 in)
spark plug
✔
plug gap
replace, if necessary
cylinder fins, intake air cooling vent
clean
✔
muffler, spark arrester, cylinder exhaust port
clean
✔
throttle lever, ignition switch
check operation
✔
replace if
cutting parts
✔
something’s wrong
gear case
grease
✔
screws/nuts/bolts
tighten/replace
✔
✔
except adjusting screws
cutting attachment guard
make sure to attach
✔
ENGINE
SHAFT
Maintenance, replacement, or repair of the emission control device and systems may be performed by any
non-road engine repair establishment or individual.
REFILLING TRIMMING LINE
1. For replacement line, use a diameter of 2.4mm(.095in).
The spool is capable for a line upto 6m(20ft) on the
10cm(4”) head. Avoid using a larger line as it may cut
down the trimming performance.
WARNING
• For safety reasons, do not use metal reinforced
line.
2. Pinch the slotted area on the both sides of the spool
housing to unhook the bottom cap.
3. Take out the spool and pull off the old line. Put one
end of new line through the spool holes and pull it
until the length is equal between each part of the line.
4. Wind up the line in the correct direction as indicated
on the spool.
5. Hook each end of the line in the slot on the edge of
the spool, and then put the ends through the eyelets
on the housing. Make sure that the spring and the
washers are in place.
6. While holding the spool against the housing, pull the
line ends to release them from the slot.
7. Line up the slot on the bottom cap with the hook on
the housing, press the cap against the housing until it
clicks.