Troy-Bilt 643B - Manuel (Page 19)

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2. When installing a single tine, be sure to position it so
that its cutting edge (sharp) will enter the soil first as
the tiller moves forward.
C. Removing/Installing a Tine Assembly:
1. A tine assembly consists of eight tines mounted on a
tine holder.
2. If removing both tine assemblies, mark them “left”
and “right” before removal. Remove the screw (C,
Figure 5-3) and locknut (D) that secure the tine
assembly to the tine shaft. If necessary, use a rubber
mallet to tap the tine assembly outward off the shaft.
3. Before reinstalling the tine assembly, inspect the
tine shaft for rust, rough spots or burrs. Lightly file or
sand, as needed. Apply a thin coat of grease to the
shaft.
4. Install each tine assembly so that the cutting (sharp)
edge of the tines will enter the soil first when the tiller
moves forward. Secure the tine assembly to the tine
shaft using the screw and locknut
CHECKING AND ADJUSTING FORWARD
DRIVE BELT TENSION
It is important to maintain correct tension on the forward
drive belt. A loose belt will cause the tines and wheels
to slow down — or stop completely — even though the
engine is running at full speed. A too tight belt can result
in unintentional tine movement when the clutch bail is in
the Neutral (released) position.
• Check belt tension after the first two hours of break-
in operation and after every 10 operating hours.
• At the end of each tilling season, check the belt for
cracks, cuts or frayed edges and replace it as soon as
possible.
To Check Forward Belt Tension:
1. Stop engine, wait for all parts to stop moving and
disconnect spark plug wire.
2. With the Forward Clutch Bail in an open (released)
position, measure and note the overall length of the
cable spring (A, Figure 5-4) by measuring from the
outermost coil to the outermost coil.
3. Squeeze the Forward Clutch Bail against the handle-
bar (see Figure 5-4) and re-measure the length of
the coils. The belt tension is correct if this second
measurement is between 1/6” -to- 3/16” longer than
the first measurement.
4. If the spring is too short (less than 1/16”), the tension
is too loose. If the spring is too long (more than 3/16”),
the tension is too tight.
5. To adjust the length of the spring:
a. Release the Forward Clutch Bail.
b. Unthread the hex nut (C, Figure 5-4) halfway up the
adjustment screw (D).
c. Unhook the top of the spring from the Forward
Clutch Bail.
d. Use pliers to prevent the adjuster (B) from turning
and turn the slotted screw located inside the spring
clockwise (viewed from operator’s position) to
increase tension on the spring. Turn the screw
counterclockwise to decrease tension. Once
adjusted, reattach the spring to the Forward Clutch
Bail.
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Figure 5-3: Install tines so that cutting edge of tines enter soil first when tiller moves forward.
5
WARNING
Do not operate tiller
on a slope too steep
for safe operation. Till
slowly and be sure
you have good footing.
Never permit tiller
to freewheel down
slopes. Failure to fol-
low this warning could
result in personal
injury.
Before clearing the
tines by hand, stop the
engine, allow all mov-
ing parts to stop and
disconnect the spark
plug wire. Remove the
ignition key on electric
start models.
Failure to follow this
warning could result in
personal injury.
Maintenance