Exmark Turf Tracer S-Series 000 & higher - Manual (Page 34)

Maintenance
Note: Do Not change hydraulic system oil (except
for what can be drained when changing filter), unless
it is felt the oil has been contaminated or been
extremely hot.
Changing oil unnecessarily could damage hydraulic
system by introducing contaminates into the system.
Hydraulic System Air Purge
Service Interval: As required
Air must be purged from the hydraulic system
when any hydraulic components, including oil
filter, are removed or any of the hydraulic lines are
disconnected.
The critical area for purging air from the hydraulic
system is between the oil reservoir and each
charge pump located on the top of each variable
displacement pump (Figure 15). Air in other parts of
the hydraulic system will be purged through normal
operation once the charge pump is “primed”.
Figure 15
1. Charge pump cap 2. Loosen 1 1/2 turns only
1. Stop engine and wait for all moving parts to stop.
Raise the rear of the machine up onto jack stands
high enough to raise the drive wheels off the
ground.
2. Check oil level as stated in Check Hydraulic Oil
Level section.
3. Start engine and move throttle control ahead to
full throttle position. Move the speed control
lever to the middle speed position and place the
drive levers in the “drive” position.
If either drive wheel does not rotate, it is possible
to assist the purging of the charge pump by
carefully rotating the tire in the forward position.
Note: It is necessary to lightly touch the charge
pump cap with your hand to check the pump
temperature. If the cap is too hot to touch, turn
off engine. The pumps may be damaged if the
pump becomes too hot.
If either drive wheel still does not rotate continue
with step 4.
4. Thoroughly clean the area around each of the
charge pump housings.
5. To “prime” charge pump, loosen two hex socket
head capscrews (shown in Figure 15) 1 1/2 turns
only. Make sure engine is not running. Lift
the charge pump housing upward and wait for
a steady flow of oil to flow out from under the
housing. Retighten the capscrews. Do this for
both pumps.
Note: Hydraulic reservoir can be pressurized up
to 5 psi to speed this process.
6. If either drive wheel still does not rotate, stop
and repeat steps 4 and 5 above for the respective
pump. If wheels rotate slowly, the system may
prime after additional running. Check oil level
as stated in Check the Hydraulic Oil Level
section.
7. Allow unit to run several minutes after the charge
pumps are “primed” with drive system in the full
speed position. Check oil level as stated in Check
the Hydraulic Oil Level section.
8. Check hydro drive linkage adjustment as stated in
Hydro Drive Linkage Adjustment section in
Adjustments.
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