Troy-Bilt 1900678 - Manual (Page 28)

C. Less than V 2 " deflection indicates that the belt is
too tight; more than 5/8" deflection indicates that it is
too loose. Use the following procedure if an adjust­
ment is required.
D. Using a
1 / 2 " wrench, slightly loosen (about V 2 turn)
the three hex nuts that secure the traction drive mount­
ing bracket to the mower housing deck. See Photo
5-12.
REPLACING THE W HEEL DRIVE BELT
(Self-Propelled Models Only)
BRACKET MOUNTING<
NUTS
Photo 5-12: Slightly loosen three hex nuts.
E. To tighten the belt, use a mallet to drive both ends
of the mounting bracket an equal distance toward the
front of the mower. See Photo 5-13. When doing so, tap
one end forward and retighten the nut on that end.
Then, tap the other end forward and retighten the nut.
To loosen the belt, move the bracket backward in a
similar manner. Make certain that both drive rollers are
equally spaced with the wheels.
Photo 5-13: Tap ends of bracket forward to tighten belt
or backward to loosen belt.
F. Check the tension on the belt as previously explained
in Step B. Repeat Steps C, D and E as necessary.
G. Tighten all three mounting nuts securely. You may
need to place a wrench on the screw heads to prevent
the screws from turning while tightening the nuts. The
screws are located at the rear of the blade housing.
Wear heavy gloves or wrap the blade with rags before
working near the blade.
H. Replace the belt/pulley safety cover, fastening it
securely.
I. Check that the clearance between the wheel friction
drive rollers and the tires is correct. See “Adjusting
Wheel Drive Traction” on Page 22.
B CAUTION: To avoid persona! injury, stop the
engine, disconnect the spark plug wire, keep
the Vi/ire away from the spark plug, and allow the
engine and muffler to coo^ before replacing the
wheel drive belt.
TOOLS NEEDED: 7/16", 1 / 2 " and two 9/16" Wrenches,
Flat Blade Screwdriver, Rubber Mallet.
A. Remove the belt/pulley safety cover by removing
the three hex nuts and two self-tapping screws.
B. Slightly loosen the three hex nuts on the traction
drive mounting bracket, as explained in Step D of the
previous “Wheel Drive Belt Tension” instructions.
C. Remove tension on the wheel drive belt and blade
drive belt by using a mallet to drive the traction drive
mounting bracket back toward the engine.
D. In the following steps, refer to Figure 5-14, which
shows the wheel and blade drive belt/pulley systems.
E. To remove the wheel drive belt, it is first necessary
to remove the biade drive belt from the blade drive rear
puliey (lower pulley) located on the engine crankshaft.
To do so, first loosen (do not remove) the screw and nut
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