Troy-Bilt 645A - Manual (Page 22)

Sections: Maintenance
WARNING
Before inspecting, cieaning or servicing the unit, shut off engine, wait for ali
parts to come to a complete stop, disconnect spark plug wire and move wire away from spark
plug. Failure to follow these instructions can result in serious personal injury or
property damage.
Figure 5-4: Lift bail and check length of Clutch Ball Spring to cheek for correct belt tension
(1-7/8“).
CHECKING AND ADJUSTING
FORWARD DRIVE BELT TENSION
Maintaining correct tension on the
forward drive belt is important to good
tilling performance and long belt life. A
loose belt will slip on the engine and
transmission pulleys and cause the tines
and wheels to slow down - or stop com­
pletely - even though the engine is
running at full speed. A loose belt can
also result in premature belt wear.
If you find you can not bring the Forward
Clutch Bail all the way up to the bottom of
the upper handlebars, you will need to
loosen the belt tension.
Also check the belt for cracks, cuts or
frayed edges and replace It as soon as
possible.
• Check belt tension after the first two
hours of initial operation (new belt).
• Check belt tension after every 10
operating hours.
To Check Forward Belt Tension:
1. Be sure that the engine is stopped and
the spark plug wire is disconnected and
moved away from the spark plug.
2. Loosen nut “C" (Figure 5-4) several
turns so it is about halfway up the
threaded adjustment screw.
3. Lift the Forward Clutch Bail up and
hold it to the bottom of the handlebars.
Measure the length of the clutch bail
spring (A, Figure 5-4) with a ruler. If the
belt tension Is correct, the length of the
coiled portion of the spring should be
approximately 1-7/8“. Nut “C” should
then be snugged down against the top of
the adjuster (B).
4. If the spring is too short, the belt
tension will be too loose. If the spring is
too long, the belt tension will be too tight.
5. To adjust the length of the spring,
release the Forward Clutch Bail. Thread
the hex nut (C, Fig. 5-4) halfway up the
adjustment screw. Turn the screw inside
the spring (A, Figure 5-4) counterclock­
wise (as viewed from the operator’s
position) while holding the adjuster (B)
steady to increase the length of the
spring, or turn clockwise (as viewed from
the operator’s position) to decrease the
length of the spring.
NOTE: If you have difficulty holding the
adjuster steady by hand, use a pliers or
wrench on the adjuster. While you turn
the screw, keep the Forward Clutch Cable
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