Trimming Technique and Performance Notes
Tilt trimmer at a slight angle from the ground. Lower to grass or
weeds you intend to cut. (If they are over 20cm (8") high, start
cutting at top.) Slowly swing unit into and out of area being cut,
holding the unit off the ground at desired cutting height.
IMPORTANT— for the best cutting action against walls, fences
and in high grass, move trimmer slowly so grass is cut WITH
THE TIP of the high speed nylon line.
1. Avoid running trimmer with hub in contact with ground.
2. Trim only when grass and weeds are dry.
3. The life of your nylon line is dependent upon following the
above trimming techniques, as well as what is being cut,
and where the cutting is being done.
EXAMPLE: Line will wear faster when run against a foundation
wall as compared to trimming around a tree. Some line breakage
will occur from feeding unit too fast, from entanglement with
foreign matter, from normal line fatigue, and from attempting to
cut thick, stalky weeds in excess of unit's capability.
Note: As the weather becomes cooler, the tendency for the
nylon line to break becomes greater.
DO NOT USE UNIT WHEN TEMPERATURE IS BELOW 50° F
4. For best performance, as the line wears, lengthen as
indicated in Line Feeding Procedure.
5. Periodically unplug extension cord at trimmer and remove
the accumulation of grass or cutting debris from the inside
of the bump cap shroud.
Telescoping height adjustment (Only for GL300-AR)
1. Unplug the extension cord at trimmer.
2. Rotate counterclockwise the knob located on the lower
body to release and pull up the upper body to adjust the
telescoping shaft until suit your height comfortably.
3. Rotate clockwise the knob and fit tight.
Spool Replacement and Recovery of Line Broken Off
1. Unplug the tool. Remove cap by pushing the two tabs in
and up, then lift off. (It is not necessary to push both tabs in
at the same time).
2. Remove any debris and grass buildup that may be inside
the cap and on the inside of the hole in the cap.
3. Remove spool by aligning he notch on the edge of the spol
with the eyelet in the hub and wipe any dirt off the ribs on
4. Unwind about 3" of line from the spool and hold it in one of
the two notches. Make sure spring is in place on the hub.
5. Holding the line in the gap, insert the end through the eyelet
in the hub and slip the spool into the hub. If the spool does
not slip into the hub easily, press gently and pull straight out
on the cutting line that protrudes through the eyelet.
6. Install cap by pushing both snap legs into the hub at once.
Make sure that both legs are snapped in one place. Pull line
out by hand until tight.
7. The line should extend out no further than the guard. You
are now ready to resume trimming.
8. The cutoff blade will automatically-trim excess line to the
Unplug Extension Cord at Trimmer
Maintain Tool With Care
1. Keep the air intake slots clean to avoid overheating which
will damage trimmer. For this cleaning, use a dry brush or
cloth to remove grass, sap or other debris.
2. Plastic parts may be cleaned by using a mild soap and a rag
dampened with hot water. Avoid all other types of detergents,
cleaners or solvents which might contain chemicals that could
seriously damage the plastic. Do not spray the trimmer with
3. Self lubricating bearings are used in the tool and periodic
relubrication is not required. However, it is recommended
that after two or three seasons of use, you take or send the
trimmer to a Black & Decker service center or authorized
service station (see TOOLS, ELECTRIC in yellow pages)
for a thorough cleaning, inspection and relubrication. If the
tool is being used professionally, the above should be
accomplished after each trimming season.
4. If trimmer fails to operate, disconnect extension cord from
power source first, then from trimmer. Make sure extension
cord is undamaged and that house fuses are not blown or
circuit breakers tripped. If trimmer still fails to operate, take
or send it to your local B&D service center or authorized
service station for repair. Do not attempt to repair it yourself.
To assure product SAFETY and RELIABILITY, repairs,
maintenance and adjustment (including brush inspection and
replacement) should be performed by authorized service centers
or other qualified service organizations, always using identical
Replacement line is available from your local dealer, or a Black
& Decker service center.
Recommended accessories for your trimmer are shown in this
manual. The use of any other accessory or attachment might be
RS300 Replacement Spool with 10 feet of Nylon Line.