SERVICE
Service Hydraulics
Changing Hydraulic Oil and Filters, ZT-3100
32
Purge port plug located
on the top of the pumps
15. Torque the purge port plugs to 180 in. lbs.
16. Continue to fill the transaxles through the expansion tank until the
“Full Cold” line is reached.
17. Re-install the expansion tank cap by hand. Be careful to not overtighten.
18. Continue with the following purge procedure.
PURGING PROCEDURE
*(If starting here, Follow numbers 1-4 of the proceeding page before continuing).
19. Start engine and idle up to 1800 rpm. Disengage parking brake.
20. Slowly move the directional controls in both forward and reverse directions
(5 or 6 times).
21. Release bypass valves.
22. Again, slowly move the directional controls in both forward and reverse
directions (5 to 6 times).
23. Stop engine. Engage parking brake. Check the oil level, and add oil as required.
24. It may be necessary to repeat Steps 19 thru 23 until all the air is completely
purged from the system.
25. Re-install rear tires and lower machine.
26. Operate machine under normal conditions, when the transaxle operates
at normal noise levels and moves smoothly forward and reverse at normal speeds,
then the transaxle is considered purged. If nessesary, repeat the purge procedure.
NOTE: Due to the effects air has on hydrostatic drive systems,
it is critical that air is purged from the systems.
The resulting symptoms of air in the hydrostatic systems may be:
1. Noisy operation.
2. Lack of power or drive after short term operation.
3. High operation temperature and excessive expansion of oil.
