Dixon 502 - Manual (Page 19)

Page 16
CARE AND MAINTENANCE - MODEL 502
DRIVE SYSTEM ADJUSTMENTS: Hydrostat Chains - Belts - Cable - Controls
Refer to the diagrams on the following pages for the location of adjustment points.
Step 1. Loosen the front and rear mounting bolts of the hydrostat, turn the rear
adjustment bolt downward, which will tension the final drive chain to the rear
wheel. Chain is correctly tensioned when at a point mid-way between the
sprockets chain free play or movement is approximately l/16th of an inch up and
down. Re-tighten mounting bolts.
Step 2. Loosen the (2) bolts which secure the front chain adjustment, refer to
diagram, turn the front adjustment bolt downward using a 5/16th alien •;
wrench. Correct tension is as in step #1. Re-tighten bolts.
Step 3. Repeat above procedures on opposite hydrostat.
Step 4. Tighten the (2) J-bolts on the T-box mounting plate until each belt has
l/8th to l/4th of an inch free play or movement at a mid-point between the
pulleys on the hydrostats and T-box.
Step 5. Position parking brake lever in the off or disengaged position. This will allow
the belt idler used on the engine to T-box to swing fully and apply tension to
the belt. At this time, check that the cable which pulls the idler to a neutral
position has approximately 1-1/2 to 2 inches of free play. If adjustment is
required, loosen the lock nuts on the cable block and turn cable sleeve in or
out to achieve desired measurement. Re-tighten lock nuts. "NOTE" Cable must have
the above dimension with parking brake released or drive belt may slip, causing
a loss of power.
Step 6. Neutral adjustment must be checked at this time which will require the engine to
be started and the parking brake released. Swing upper control levers outward
and into neutral slots, start engine, use caution when releasing parking brake
as mower may tend to creep or move prior to re-adjustment of neutral settings on
each hydrostat. If adjustment is required, loosen lock nuts at each end of the
control rods and back off the tension bolt on each spring block. Turn control
rod in or out until neutral is obtained on each hydrostat. Re-tighten lock nuts
and tension bolts on spring blocks.
Step 7. Stop engine, move levers to drive position. Lightly push each upper control
lever forward until a resistance is felt on the lever. At this time, check that
the forward lever stops are hitting against stop block. "NOTE: Do not allow
levers to travel to completely forward without hitting stop blocks as damage to
hydrostats could result. If adjustment is required, loosen lock nut on lever
stop and turn bolt in to allow lever to hit the stop before resistance is felt in
the hydrostat.
Step 8. Start engine. Drive mower forward and observe driving condition. If mower tends
to pull to either side, re-adjust lever stop on fast side to slow that hydrostat
down and even out the ground speed. Do not speed up slow side as over stroking
of the hydrostat could result in damage to the unit. If upper control levers are
slightly off-set after this adjustment, they can be realigned by bending them
into alignment.