John Deere stx38 - Manual (Page 198)

5 - 34
3/21/97
TESTS AND ADJUSTMENTS POWER TRAIN
TESTS AND ADJUSTMENTS
CLUTCH/BRAKE PEDAL LINKAGE
AND TRACTION DRIVE SYSTEM
Reason:
To ensure clutch/brake pedal linkage and traction drive
system maintains traction in all three lower gears up a
17° slope. Also, to ensure it disengages traction drive
belt, engages brake to slow down or stop tractor within
a specified distance, and holds tractor stationary in
PARK position on a 17° slope or less.
Procedure:
NOTE: This is a four part test and adjustment
procedure:
• Test drive on 17° slope,
• Brake spring adjustment,
• Clutch spring adjustment,
• Repeat test drive on 17° slope.
Test Drive—
1. Test drive tractor to see if traction drive system
pulls tractor up a 17° slope in all three lower gears.
2. Look for a steady pull in all three lower gears up the
slope.
3. If traction test fails in any or all of the three lower
gears, the belt tension must be adjusted.
4. Drive or push tractor onto a 17° slope and lock
clutch/brake pedal in PARK position.
5. Park brake must hold tractor stationary on
slope and tractor must not creep downward
once park brake is set.
6. Drive tractor on dry pavement in a safe, open, and
level area at fast idle in high gear. Apply a “panic
stop” force (no more than 50 pounds of force) to
brake pedal—tractor must stop within 0.9—1.5
M (3—5 ft) and both wheels should lock-up,
leaving skid marks on pavement.
7. Repeat Steps 4—6 for reverse.
8. If any test fails, the clutch and brake linkages must
be adjusted or components replaced.
IMPORTANT: Anytime the brake or clutch spring
need to be adjusted, both must be examined to
ensure desired results will be obtained.
BRAKE SPRING ADJUSTMENT
IMPORTANT: Anytime the brake or clutch spring
needs to be adjusted, both must be examined to
ensure desired results will be obtained.
1. First check for brake disc contacting the case (1)
and/or brake lever contacting its mounting bracket
(2), top or bottom. Clearance between friction
pucks and disc should be 0.254—0.508 mm
(0.010—0.020 in.). If necessary, replace friction
pucks and disc before making any adjustments.
c
CAUTION
DO NOT engage clutch/brake pedal too
aggressively or tractor may tip over backwards
while performing the test drive on a 17° slope.
M42597
M42598
M58279
Contact Points
2 1