5.1.9Change hydraulic system filter.
Service Interval: After First 250 hrs, then yearly thereafter.
Note: Use only Exmark Part No. 513211 for Summer use above 32° F (0° C) or Part No. 523541 for Winter use below 32° F (0° C). Refer to 2.7.2 for filter specifications.
a)Place unit on a level surface, stop engine and wait for all moving parts to stop. Remove ignition key or spark plug wire(s).
b)Carefully clean area around filter. It is important that no dirt or contamination enters the hydraulic system.
c)Unscrew filter to remove and allow oil to drain from reservoir.
IMPORTANT: Before
d)Fill reservoir as stated in Section 5.1.8.
e)Loosen filter 1/2 turn and allow a small amount of oil to leak from the oil filter (this allows air to be purged from the oil filter and supply hose from the hydraulic reservoir). Turn filter clockwise until rubber seal contacts the filter adapter. Then tighten the filter an additional 2/3 to 3/4 turn.
f)Raise the rear of the machine up onto jack stands high enough to raise the drive wheels off of the ground. Run machine to allow any other air to be purged from the hydraulic system and recheck the oil level.
g)If either drive wheel does not rotate, one or both of the charge pumps (located on the top of the main pump as shown in Figure 9) may have lost their “prime”. Refer to Section 5.1.10.
h)DO NOT change hydraulic system oil (except what can be drained when changing filter) unless it is felt that oil has been contaminated. Changing oil unnecessarily could damage the hydraulic system by introducing contaminates into the system.
5.1.10Hydraulic system air purge procedure.
Air must be purged from the hydraulic system when any hydraulic components, including the 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 (See Figure 9).
Air in other parts of the hydraulic system will be purged through normal operation once the charge pumps are “primed”.
a)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.
b)Check oil level as stated in Section 5.1.8.
c)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 direction.
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 (d).
-28 -