Hydraulic Pump; Fluid Change; Purging Procedures - Husqvarna MZ25 / 968999780 Operator's Manual

Hydraulic Pump

Fluid Change

This transaxle is designed with an external filter for
ease of maintenance. To ensure constant fluid quality
levels and longer life an oil filter change interval of
every 200 hours is recommended.
The following procedure can be performed with the
pump installed in the vehicle, and the vehicle on level
ground. Apply the bypass valve and lock the vehicle
parking brake.
1. Place an oil drain pan with a two gallon
capacity beneath the oil filter. Remove the
oil filter from the pump.
2. After the oil has drained, wipe the filter
base surface off and apply a film of new oil
to the gasket of the new replacement filter.
3. Prefill the oil filter with new oil and
the new filter by hand. Turn ¾ to one full
turn after the filter gasket contacts the filter
base surface.
4. Drain old oil filters of all free-flowing
oil prior to disposal. Place used oil in
appropriate containers and dispose of it in
accordance with laws in your area.
5. Remove the cap from the pump's tank
located on the vehicle frame.
6. Fill reservoir with SAE 10W30 oil to just
above the MIN-ADD line on the reservoir.
After purging, check levels and add oil if
necessary.
7. Reinstall the tank cap by hand. Do not
overtighten.
8. Proceed to the purge procedure.

Purging Procedures

Due to the effects air has on efficiency in hydrostatic
drive applications, it is critical to purge the system.
These purge procedures should be implemented
any time a hydrostatic system has been opened to
facilitate maintenance or any additional oil has been
added to the system.
Resulting symptoms in 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.
4. Shortened component life.
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English
lUBRICATION
3
install
1. Pump filter
2. Pump reservoir
3. Fluid fill lines
Changing the hydraulic pump oil filter
Before starting, make sure the pump is at the proper oil
level. If not, fill to the specifications outlined prior.
The following procedures are best performed with the
vehicle drive wheels off the ground, then repeated
under normal operating conditions.
1.
2.
3.
4.
5.
2
Disengage the brake if activated.
With the bypass valve open and the
engine running at fast idle, slowly move
the directional control in both forward and
reverse directions (5 or 6 times). As air is
purged from the unit, the oil level will drop.
With the bypass valve closed and the
engine running, slowly move the directional
control in both forward and reverse
directions (5 to 6 times). Check the oil level
and add oil as required after stopping the
engine.
It may be necessary to repeat Steps 2 and
3 until all the air is completely purged from
the system. When the transaxle operates
at normal noise levels and moves smoothly
forward and reverse at normal speeds, the
transaxle is considered purged.
After the vehicle has been used two times,
the oil level should be checked while the oil
is cold and adjusted accordingly.
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8061-016