Maintenance
5.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.
6.Raise the rear of machine up and support with jack stands (or equivalent support) just high enough to allow drive wheels to turn freely.
7.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 13) may have lost their “prime”. Refer to Hydraulic System Air Purge section.
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 13). Air in other parts of the hydraulic system will be purged through normal operation once the charge pump is “primed”.
Figure 13
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 13) 1 1/2 turns only. Make sure engine is not running. Lift the charge pump housing upward and wait for
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