Troy-Bilt 21AE682W766 Operator's Manual page 20

Checking and Adjusting the Reverse Drive System
When the Wheels/Tines/PTO Drive Lever is moved up
into REVERSE, the engine and engine mount move
down to press on the reverse adjustment bolt. See
Figure 5-19.
Figure 5-19
This action compresses the reverse spring and
plunger assembly, requiring you to hold the lever up
in REVERSE. When you release the lever, the spring
automatically pushes the lever back into NEUTRAL
position.
The spring and plunger assembly is designed to
prevent the reverse disc from making contact with
the transmission pulley until you shift into REVERSE.
When the lever is in NEUTRAL, the switch body on
the bottom of the engine mount tab should be
resting squarely on top of the reverse adjustment
bolt. See Figure 5-19. The reverse adjustment bolt
can be adjusted up or down to correct a number of
reverse drive operating problems, as explained next.
Checking and Adjusting the Reverse Disc
1. Verify that the linkages for Wheels/Tines/PTO
Drive Lever are lubricated with oil and engine
mount bars and belt adjustment block are
lubricated with grease. See Lubrication earlier
in this section.
2. Place Wheels/Tines/PTO Drive Lever in
NEUTRAL. Briefly pull out the engine recoil
starter handle while watching the reverse
disc. The disc should turn, but lower pulley
should not. See Figure 5-20. If the reverse disc
turns the lower pulley, or if it is located closer
than 3⁄16" to the pulley, reverse adjustment
bolt should be adjusted upward. Moving the
adjustment bolt upward will also solve the
problem of a tiller that goes into REVERSE on
its own.
Figure 5-20
20 S 5 — S
ection ervice
3. Use your left hand to hold the Wheels/Tines/
PTO Drive Lever up in REVERSE, while briefly
pulling out the engine recoil starter. The
reverse disc should turn the lower pulley.
See Figure 5-21. If not, or it requires a lot of
pressure to hold the lever up in REVERSE, then
the reverse adjustment bolt must be adjusted
downward. When correctly adjusted, the
Wheels/Tines/PTO Drive Lever should pop out
of reverse when the lever is released, but not
require exceptional effort to hold it up in the
Switch Body
reverse position.
Adjustment
Bolt
Spring and
Plunger
4. Shift the Wheels/Tines/PTO Drive Lever
to REVERSE and then let it go. The lever
should return to NEUTRAL. If not, the reverse
adjustment bolt will have to be adjusted
upward.
Adjusting the Reverse Drive:
1. Place the Wheels/Tines/PTO Drive Lever in
FORWARD position.
2. On the left side of the tiller, put a 1⁄2" wrench
on the plunger retaining bolt and another 1⁄2"
wrench on the jam nut next to it. See Figure
5-22.
Recoil Starter
Handle
3. While holding the bolt steady, loosen the jam
Reverse
nut (counterclockwise) until it touches the bolt
Disc
head.
4. Turn the bolt in until it tightens against the
plunger inside the spring. The bolt must be
tight to prevent the plunger from turning —
be careful not to overtighten and break the
bolt.
Recoil Starter
Handle
Reverse
Disc
Wheels/Tines/PTO
Drive Lever
Figure 5-21
Jam Nut
Retaining Bolt
Figure 5-22
5. Place a 7⁄8" wrench on the head of the reverse
adjustment bolt and a 9⁄16" wrench on the jam
nut below it. See Figure 5-23. Hold the bolt
steady while loosening the jam nut three or
four turns.
Adjustment
Bolt
Jam Nut
Figure 5-23
6. Move the Wheels/Tines/PTO Drive Lever to
NEUTRAL. The switch body on the bottom
of the engine mount tab should be resting
squarely on top of the reverse adjustment
bolt, and the reverse disc should be at least
3⁄16" away from the transmission drive pulley.
See Figure 5-19. If the reverse disc is any closer
than this, raise the reverse adjustment bolt
(turn it counterclockwise).
7. Check that the reverse disc is at least 3⁄16" away
from the transmission drive pulley. Then hold
the reverse adjustment bolt steady with one
wrench while tightening the jam nut with a
second wrench. See Figure 5-23.
8. Place a chalk or pencil mark on the top edge
of the plunger retaining bolt. Now, while
watching the mark, loosen the bolt 3⁄4-turn.
See Figure 5-24. Do not exceed a 3⁄4 turn. This
would disengage the bolt from the locking
groove in the side of the plunger.
Plunger
Retaining Bolt
Figure 5-24
9. Hold the plunger retaining bolt steady with a
wrench while tightening the jam nut against
the side of the plunger housing. See Figure
5-22.
10. Check the action of the reverse disc as
explained previously.
NOTE: If the above adjustments have not
corrected an improperly working reverse
drive, contact an authorized dealer or the
TROYBILT Technical Service Department for
assistance.