16
SAW CHAIN TENSION ADJUSTMENT
Proper tension of saw chain is extremely important and
must be checked before starting, as well as during any
cutting operation.
Taking the time to make needed adjustments to the saw
chain will result in improved cutting performance and
prolonged chain life.
To asjust the saw chain:
1. Loosen the bar retaining nut(s) (B, Fig. 22). Hold nose
of guide bar up and turn adjustment screw (D)
COUNTERCLOCKWISE to increase chain tension.
Turning screw CLOCKWISE will decrease amount of
tension on chain. Ensure the chain fits snugly all the
way around the guide bar (Fig. 28).
Always use
protective gloves
when handling the saw chain.
WARNING:
A
C
B
Fig. 29
2. After making adjustment, and while still holding nose
of bar in the uppermost position, tighten the bar
retaining nut securely. Chain has proper tension
when it has a snug fit all around and can be pulled
around by gloved hand.
NOTE: If chain is difficult to rotate on guide bar or if it
binds, too much tension has been applied. This
requires minor adjustment as follows:
A. Loosen the bar retaining nut so it is finger tight.
Decrease tension by turning the bar adjustment
screw CLOCKWISE slowly. Move chain back and
forth on bar. Continue to adjust until chain rotates
freely, but fits snugly. Increase tension by turning bar
adjustment screw COUNTERCLOCKWISE.
B. When saw chain has proper tension, hold nose of bar
in uppermost position and tighten the bar retaining
nut securely.
A new saw chain
stretches, requiring
adjustment after as few as 5 cuts. This is normal
with a new chain, and the interval between
future adjustments will lengthen quickly.
CAUTION:
If saw chain is TOO
LOOSE or TOO
TIGHT, the sprocket, bar, chain, and
crankshaft bearings will wear more rapidly.
Study Fig. 29 for information concerning
correct cold tension (A), correct warm
tension (B), and as a guide for when saw
chain needs adjustment (C).
CAUTION:
Fig. 30
CHAIN BRAKE MECHANICAL TEST
Your chain saw is equipped with a
Chain Brake® that
reduces possibility of injury due to kickback. The brake
is activated if pressure is applied against brake lever
when, as in the event of kickback, operator’s hand
strikes the lever. When the brake is actuated, chain
movement stops abruptly.
To Test the
Chain Brake®:
1. The
Chain Brake® is DISENGAGED (chain can
move) when BRAKE LEVER IS PULLED BACK AND
LOCKED (A, Fig. 24).
2. The
Chain Brake® is ENGAGED (chain is stopped)
when brake lever is in forward position. You should
not be able to move chain (B, Fig. 30).
NOTE: The brake lever should snap into both positions.
If strong resistance is felt, or lever does not move
into either position, do not use your saw. Take it
immediately to a Authorized Service Center for
repair. Call 1-800-520-5520 for more information.
The purpose of the
Chain Brake® is to
reduce the possibility of injury due to
kickback; however, it cannot provide the
intended measure of protection if the saw is
operated carelessly.
Always test the Chain Brake® before using
your saw and periodically while on the job.
WARNING:
A
B
MAINTENANCE AND REPAIR INSTRUCTIONS
D
Fig. 28
Summary of Contents for TB5018CC, TB5020CC
Page 44: ...E22 NOTAS...
Page 45: ...E23 NOTAS...
Page 46: ...E24 NOTAS...
Page 47: ...E25 PARTS LIST...
