Troy-Bilt TB5518 Operator'S Manual Download

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MAINTENANCE AND REPAIR INSTRUCTIONS

ADJUSTING THE CHAIN TENSION

The chain must be tensioned whenever the flats on the drive links
hang out of the bar groove (Fig. 30). Check for proper chain tension
before starting the unit and periodically during operation.

NOTE:

A new chain tends to stretch. Check the chain tension
frequently and tighten as required.

1. Stop the engine, wait for all moving parts to stop, allow the unit to

cool, disconnect the spark plug wire and disengage the chain brake.

2. Slightly loosen the bar-retaining nuts (Fig. 31).

3. Hold the guide bar tip up and rotate the chain-tensioning screw

(Fig. 32) clockwise with a standard screwdriver to tension the
chain. The desired tension depends on the temperature of the
chain:

•

Cold Chain Tensioning

- A cold chain is correctly tensioned

when there is no sag on the underside of the guide bar and the
chain seats snugly against the guide bar with the drive links in
the bar groove.

•

Warm Chain Tensioning

- During normal operation, the

temperature of the chain will increase. The drive links of a
correctly tensioned warm chain will hang approximately 1/16
inch (1.3 mm) out of the bar groove (Fig. 33).

4. Once adjusted, lift the tip of the guide bar up to check for proper

tension (Fig. 34). If the chain is still too loose, release the tip of the
guide bar and turn the chain-tensioning screw 1/2 turn clockwise.
Repeat this process until the desired tension is achieved.

NOTE:

If the chain is too tight, it will not rotate. To loosen the chain,
turn the chain-tensioning screw 1/4 turn counterclockwise.
Ensure that the chain can be turned by hand without binding
(Fig. 35). Also note that the chain will not rotate if the chain
brake is engaged.

5. Hold the tip of the guide bar up and securely tighten the bar-

retaining nuts.

REMOVING/REPLACING THE GUIDE BAR AND CHAIN

Use only a low-kickback saw chain that has met kickback
performance per ANSI B175.1 for this saw. This fast-cutting chain
provides kickback reduction when properly maintained.

NOTE:

When replacing the guide bar and chain, use only
manufacturer suggested replacement parts. The use of any
other parts may create a hazard or cause product damage
and will VOID the warranty.

Removing the Old Guide Bar and Chain

1. Make sure the engine is off and the spark plug wire is

disconnected. Disengage the chain brake.

2. Remove the bar-retaining nuts with the supplied multi-purpose

tool. Remove the guide bar cover and guide bar plate by pulling
them straight out (Fig. 31).

3. Remove the guide bar and chain from the mounting surface.

4. Remove the old chain from the guide bar.

Installing the New Guide Bar and Chain

1. Lay out the new saw chain in a loop and straighten any kinks. The

cutters on the top of the guide bar should face toward the guide
bar tip in the direction of chain rotation (Fig. 36). If they face
backward, turn the loop over.

2. Place the chain drive links into the bar groove as shown (Fig. 37).

NOTE:

Make sure the chain is correctly installed and the cutters are
facing in the correct direction (Fig. 36).

3. Position the chain so there is a loop at the back of the guide bar.

4. Hold the chain in position on the guide bar and place the loop

around the drive sprocket.

5. Fit the guide bar flush against the mounting surface so that the

two guide bar bolts are in the guide bar slot (Fig. 31).

NOTE:

Make sure that the chain-tensioning pin is in the chain-
tensioning pin hole (Fig. 38).

6. Replace the guide bar plate so that the bent edges (top and

bottom) are directed away from the chain.

7. Replace the guide bar cover and bar-retaining nuts. Tighten the

bar-retaining nuts hand tight.

NOTE:

Do not over-tighten the bar-retaining nuts. The guide bar
should still be free to move for chain tension adjustment.

8. Adjust the chain tension. Refer to the

Adjusting the Chain Tension

instructions above.

ADJUSTING THE AUTOMATIC OILER

The oiler automatically delivers the proper amount of oil to the guide
bar and saw chain. As the engine speed increases, so does the oil
flow. The amount of oil flowing to the guide bar and saw chain may
be changed by turning the adjustment screw with a small standard
screwdriver. Turn the screw clockwise to decrease oil flow or turn the
screw counterclockwise to increase oil flow (Fig. 39).

Flats

Fig. 30

Approx 1/16”

(1.3 mm)

Fig. 33

Fig. 31

Fig. 32

Fig. 36

Fig. 37

Fig. 34

Fig. 35

WARNING:

Before inspecting, cleaning or servicing the unit, stop the engine, wait for all moving parts

to stop, allow the unit to cool, disengage the chain brake and disconnect the spark plug wire to ensure
that the unit cannot start. Failure to follow these instructions can result in serious personal injury or
property damage.

WARNING:

To avoid possible serious injury, never

touch or adjust the chain while the engine is running.
The saw chain is very sharp; always wear protective
gloves when performing maintenance on the chain.

CAUTION:

A chain tensioned while warm, may be

too tight upon cooling. Check the “cold tension”
before next use.

MAINTENANCE AND REPAIR INSTRUCTIONS

Guide Bar Plate

Guide Bar Cover

Bar-retaining Nuts

Guide

Bar Slot

Chain-tensioning Screw

Chain Drive

Links

Chain

Rotation

Cutters

Bar Groove

Chain Drive

Links

Bar Tip

PRUNING

Pruning is the process of trimming limbs from a live tree (Fig. 28).

• Work slowly, while maintaining a proper grip and stance.

• Do not cut from a ladder; this is extremely dangerous. Leave this

operation for professionals.

• Do not cut above chest height, as a saw held higher is difficult to control during kickback.

• When pruning trees it is important not to make the finishing cut next to the main limb or trunk until the limb is cut

further out to reduce the weight. This prevents stripping the bark from the main member.

1. Underbuck the branch 1/3 through for the first cut.

2. The second cut should overbuck to drop the branch off.

3. Make the finishing cut smoothly and neatly against the main member so the bark will grow back to seal the wound.

CUTTING SPRINGPOLES

A springpole is any log, branch, rooted stump, or sapling that is bent
under tension by other wood so that it springs back if the wood
holding it is cut or removed (Fig. 29). On a fallen tree, a rooted stump
has a high potential of springing back to the upright position during
the bucking cut to separate the log from the stump.

Fig. 28

Fig. 29

Load

First Cut

1/3 Diameter

Finishing Cut

Second Cut

Springpole

WARNING:

If the limbs to be pruned are above

chest height, hire a professional to perform the pruning.

WARNING:

Watch for springpoles; these can

strike the operator, causing serious personal injury.

Pruning

WARNING:

Use caution when pruning heavy

branches. Falling branches can cause serious injury.
Always wear head protection, plan a safe exit from the
path of falling limbs and stay alert.

OPERATING INSTRUCTIONS

MAINTENANCE SCHEDULE

Perform these required maintenance procedures at the frequency stated in the table. These procedures should also be
a part of any seasonal tune-up.

NOTE:

Maintenance, replacement or repair of the emission control devices and system may only be performed by an
authorized service center.

A good preventive maintenance program of regular inspection and care will increase the life and improve performance
the unit. This maintenance checklist is a guide for such a program.

Cleaning, adjusting and part replacement may be required, under certain conditions, at more frequent intervals than
those indicated.

CUSTOMER RESPONSIBILITY

MAINTENANCE CHECKLIST

ACTION

BEFORE EACH

USE

AFTER EACH

USE

AFTER EVERY

10 HOURS OF

OPERATION

AFTER EVERY