Maintenance - Hitachi CS 33EB Handling Instructions Manual

FELLING CUT, TRUNK DIAMETER MORE THAN TWICE GUIDE
BAR LENGTH
Cut a large, wide notch. Then cut a recess into the center of the
notch. Always leave a hinge on both sides of the center cut. (Fig. 23)
Complete the felling cut by sawing around the trunk as in the Fig. 24.
WARNING
These methods are extremely dangerous because they involve
the use of the nose of guide bar and can result in kickback.
Only properly trained professionals should attempt these
techniques.
LIMBING
Limbing is removing the branches from a feller tree.
WARNING
A majority of kickback accidents occur during Iimbing.
Do not use the nose of the guide bar. Be extremely cautious and
avoid contacting the log, other limbs or objects with the nose
of the guide bar. Be extremely cautious of limbs under tension.
They can spring back towards you and cause loss of control
resulting in injury. (Fig. 25)
Stand on the left side of the trunk. Maintain a secure footing and rest
the chain saw on the trunk. Hold the chain saw close to you so that
you are in full control of it. Keep well away from the chain. Move only
when the trunk is between you and the chain. Watch out for spring
back of limbs under tension.
LIMBING THICK BRANCHES
When limbing thick branches, the guide bar may get pinched easily.
Branches under tension often snap up, so cut troublesome branches
in small steps. Apply the same principles as for cross cutting. Think
ahead and be aware of the possible consequences of all your
actions.
CROSS CUTTING/BUCKING
Before starting to cut through the log, try to imagine what is going to
happen. Look out for stresses in the log and cut through it in such a
manner that the guide bar will not get pinched.
CROSS CUTTING LOGS, PRESSURE ON TOP
Take a fi rm stance. Begin with an upper cut. Do not cut too deeply,
about 1/3 of the log diameter is enough. Finish with a bottom cut.
The saw cuts should meet. (Fig. 26)
27. Relieving cut
28. Cross cut
29. Pressure on top
30. Pressure side
31. Tension side
32. Relative depth of saw cuts
THICK LOG, LARGER THAN GUIDE BAR LENGTH
Begin by cutting on the opposite side of the log. Pull the chain saw
towards you, followed by previous procedure. (Fig. 27)
If the log is lying on the ground make a boring cut to avoid cutting into
the ground. Finish with a bottom cut. (Fig. 28)
WARNING
KICKBACK DANGER
Do not attempt a boring cut if you are not properly trained. A
boring cut involves the use of the nose of the guide bar and can
result in kickback.
CROSS CUTTING LOGS, PRESSURE ON BOTTOM
Take a fi rm stance. Begin with a bottom cut. The depth of the cut
should be about 1/3 of the log diameter.
Finish with an upper cut. The saw cuts should meet. (Fig. 29)
33. Relieving cut
34. Cross cut
35. Pressure on bottom
36. Tension side
37. Pressure side
38. Relative depth of saw cuts
THICK LOG, LARGER THAN GUIDE BAR LENGTH
Begin by cutting on the opposite side of the log. Pull the chain saw
towards you, followed by previous procedure. Make a boring cut if
the log is close to the ground. Finish with a top cut. (Fig. 30)
WARNING
KICKBACK DANGER
Do not attempt a boring cut if you are not properly trained. A
boring cut involves the use of the nose of the guide bar and can
result in kickback. (Fig. 31)
IF THE CHAIN SAW GETS STUCK
Stop the engine. Raise the log or change its position, using a thick
branch or pole as a lever. Do not try to pull the chain saw free. If you
do, you can deform the handle or be injured by the saw chain if the
chain saw is suddenly released.

MAINTENANCE

Carburetor adjustment (Fig. 32)
In the carburetor, fuel is mixed with air. When the engine is test run at
the factory, the carburetor is adjusted. A further adjustment may be
required, according to climate and altitude. The carburetor has one
adjustment possibility:
T = Idle speed adjustment screw.
Idle speed adjustment (T)
Check that the air fi lter is clean. When the idle speed is correct, the
cutting attachment will not rotate. If adjustment is required, close
(clockwise) the T-screw, with the engine running, until the cutting
attachment starts to rotate. Open (counter-clockwise) the screw
until the cutting attachment stops. You have reached the correct idle
speed when the engine runs smoothly in all positions well below the
rpm when the cutting attachment starts to rotate.
If the cutting attachment still rotates after idle speed adjustment,
contact Hitachi Authorized Service Centers.
WARNING
When the engine is idling the cutting attachment must under no
circumstances rotate.
NOTE
Do not touch the High speed adjustment (H) and the Low speed
adjustment (L).
Those are only for Hitachi Authorized Service Centers.
If you rotate them, it will cause a serious damage to the machine.
Air fi lter (Fig. 33)
The air fi lter (39) must be cleaned from dust and dirt in order to avoid:
○ Carburetor malfunctions.
○ Starting problems.
○ Engine power reduction.
○ Unnecessary wear on the engine parts.
○ Abnormal fuel consumption.
Clean the air fi lter daily or more often if working in exceptionally
dusty areas.
Remove the air fi lter cover (40) and the fi lter (39).
Rinse them in warm soap suds. Check that the fi lter is dry before
reassembly. An air fi lter that has been used for some time cannot be
cleaned completely. Therefore, it must regularly be replaced with a
new one. A damaged fi lter must always be replaced.
Spark plug (Fig. 34)
The spark plug condition is infl uenced by:
○ An incorrect carburetor setting.
○ Wrong fuel mixture (too much oil in the gasoline)
○ A dirty air fi lter.
○ Hard running conditions (such as cold weather).
These factors cause deposits on the spark plug electrodes, which
may result in malfunction and starting diffi culties. If the engine is
low on power, diffi cult to start or runs poorly at idling speed, always
check the spark plug fi rst. If the spark plug is dirty, clean it and check
the electrode gap. Readjust if necessary. The correct gap is 0.6 mm.
The spark plug should be replaced after about 100 operation hours
or earlier if the electrodes are badly eroded.
NOTE
In some areas, local law requires using a resistor spark plug
to suppress ignition signals. If this machine was originally
equipped with resistor spark plug, use same type of spark plug
for replacement.
English
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