Operation Manual

13
follow the safety rules stated in this instruction
manual may cause serious personal injury.
DESIGNATION OF PARTS
(Nut model: the sprocket cover is tightened by nuts.)
For Model UC3050A, UC3550A, UC3550AP, UC4050A,
UC4550A (Fig. 5)
(Lever model: the sprocket cover is tightened by lever.)
For Model UC3051A, UC3551A, UC4051A, UC4551A
(Fig. 6)
(For all models) (Fig. 7)
ASSEMBLY
CAUTION:
• Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
Removing or installing sprocket cover
To remove the sprocket cover, perform the following
steps:
(For nut models) (Fig. 8)
Loosen the nut.
(For lever models) (Fig. 9)
Press and fully open the lever until it stops.
Turn the lever counterclockwise.
To install the sprocket cover, perform the above steps in
reverse.
Removing or installing saw chain
CAUTION:
• Always wear gloves when installing or removing the
saw chain.
To remove the saw chain, perform the following steps:
1. Loosen the sprocket cover.
2. (For nut models) Turn the chain adjusting screw
counterclockwise to release the saw chain tension.
(For lever models) Turn the adjusting dial to “-”
direction to loosen the saw chain tension. (Fig. 10 &
11)
3. Remove the sprocket cover.
4. Remove the saw chain and guide bar from the chain
saw.
To install the saw chain, perform the following steps:
5. Make sure the direction of the chain. The arrow mark
on the chain shows the direction of the chain. (Fig. 12)
6. Fit in one end of the saw chain on the top of the guide
bar and the other end of it around the sprocket.
7. Place the guide bar on the chain saw.
8. Align the tension slide with the hole of the guide bar.
(Fig. 13)
9. Holding the guide bar, and turn the chain adjusting
screw/dial to adjust the saw chain tension.
10. Place the sprocket cover so that the hooks fit
alongside the holes and the pin fits its counterpart on
the sprocket cover. (Fig. 14)
11. Tighten the sprocket cover. (Fig. 15 & 16)
Adjusting saw chain tension
The saw chain may become loose after many hours of
use. From time to time check the saw chain tension
before use.
1. Loosen the sprocket cover lightly.
2. Lift up the guide bar tip slightly.
3. Turn the adjusting screw/dial to adjust saw chain
tension. (Fig. 17 & 18)
4. Tighten the saw chain until the lower side of the saw
chain fits in the guide bar rail (see circle).
5. Keep holding the guide bar lightly, tighten the sprocket
cover after adjusting the chain tension. Make sure that
the saw chain does not loose at lower side.
Make sure the saw chain fits snugly against the lower side
of the bar.
CAUTION:
• Do not tighten the saw chain too much. Excessively
high tension of saw chain may cause breakage of saw
chain, wear of the guide bar and breakage of the
adjusting dial.
• A chain which is too loose can jump off the bar, and
therefore presents an accident risk.
• Carry out the procedure of installing or removing saw
chain in a clean place free from sawdust and the like.
Engaging extension cord
CAUTION:
• Make sure that the extension cord is unplugged to the
mains outlet. (Fig. 19)
When engaging the extension cord, secure it to the chain
saw’s cord with the cord hook.
Attach the cord hook about 100 - 200 mm from the
extension cord connector. This helps prevent
unintentional disconnection.
OPERATION
CAUTION:
• Hold the tool firmly with right hand on the rear handle
and left hand on the front handle when performing the
tool.
Switch action (Fig. 20)
CAUTION:
• Always be sure that the tool is switched off and
unplugged before checking function on the switch
trigger.
• Before plugging in the tool, always check to see that
the switch trigger actuates properly and returns to the
“OFF” position when released.
To prevent the switch trigger from being accidentally
pulled, a lock-off button is provided.
To start the tool, depress the lock-off button and pull the
switch trigger. Release the switch trigger to stop.
Lubrication
CAUTION:
• Always be sure that the tool is switched off and
unplugged before lubricating the saw chain.
Lubricate the saw chain and bar using biologically
degradable saw chain oil with an adhesion agent. The
adhesion agent in the saw chain oil prevents the oil from