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15
Section 5: Maintenance/Repairs
CHANGING TRIMMER/
MOWER LINES
Replace the trimmer lines when they
wear to the point that trimming and
mowing projects take too long and re-
quire too much movement. A good
rule of thumb is to change the lines
when they reach half their original
length.
To Change Trimmer Lines:
1. Stop engine, allow all moving parts
to stop and then disconnect the spark
plug wire and move it away from the
spark plug. Remove the ignition key on
electric start models. DO NOT tip the
machine. DO NOT touch the metal
wear cup on the bottom of the spindle
head. This surface may be hot.
NOTE: The two lines are held in place
with two steel clamp plates, each
clamp permanently secured by a bolt
and a nut. Do not attempt to remove
the nuts—it is not necessary to remove
them in order to change the trimmer
lines.
2. Use a 1/2" open-end wrench to
loosen the nut (A, Figure 5-11) on one
clamp plate (B) until the clamp plate is
loose. Slide the old line out and discard
it. Clean out the groove underneath the
clamp plate very thoroughly.
3. Feed the new 18" long trimmer line
under the clamp plate, positioning it as
far back as possible next to the arc
(into the groove) of the trimmer head,
so the downward-facing prongs of the
clamp plate make contact with the line.
(Putting gentle downward pressure on
the outer edge of the clamp plate will
ease installation.) See Figure 5-12 to
see how the new line should be posi-
tioned. An equal amount of line should
project out from each side of the clamp
plate, creating an overall 22" wide cut-
ting swath. You may offset both trim-
mer lines somewhat to increase the
cutting swath up to 25" wide. DO NOT
offset the line so that the overall cutting
swath is greater than 25". See Warning
statement at right.
NOTE: Whether replacing one or both
lines, they must both be .130" or .155"
in diameter.
4. If bottom of trimmer head is
equipped with two brackets (see Figure
5-13), position prongs on brackets as
shown by large arrows in Figure 5-13.
5. While holding the clamp plate (B,
Figure 5-11) in position on the line (be
sure prongs on clamp plate are in con-
tact with the line), retighten the nut (A)
to 75 in/lbs. Do not overtighten.
6. Repeat steps 2 through 5 to replace
the second trimmer line.
WARNING
Offsetting the trimmer lines
causes the lines to rotate
faster than when they project
an equal length on each side.
This increases the chance of
loose materials being dis-
lodged and propelled at high
speeds.
Failure of the operator to
wear safety goggles and ap-
propriate clothing and to
keep bystanders away can re-
sult in severe personal injury
or property damage.
Figure 5-11: Slide a new section of trim-
mer line underneath the clamp plate (B),
then retighten the nut (A) securely to
hold the trimmer line in place.
A
B
Figure 5-12: Correct position of newly in-
stalled line.
PRESS
DOWN
HERE
Insert in this Direction
Figure 5-13: On bottom of trimmer head,
position brackets (if so equipped) as
shown before tightening nuts on clamp
plates.
WARNING
Before inspecting, cleaning or servicing the unit, shut off engine, wait for all parts
to come to a complete stop, disconnect spark plug wire and move wire away from spark plug.
Remove ignition key on electric start models. Failure to follow these instructions can result in
serious personal injury or property damage.