Transmission Purging - Husqvarna MZ 52 Operator's Manual

3. After the oil has drained, wipe the filter base
surface and apply a film of new oil to the gasket of
the replacement filter.
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.
4. Install the new filter by hand, turning it three-
quarters to one full turn after the filter gasket
contacts the filter base surface.
5. Reinstall the filter guard. Torque screws to
65 in/lbs. each.
6. Repeat steps on the opposite side.
7. 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.
8. Remove the top port plug (see illustration) from
the left side and right side of the transaxles prior
to filling with oil. This will allow the transaxles to
vent during oil fill.
9. Remove the cap from the transaxles' expansion
tank located on the vehicle frame.
10. Fill with 20W50 motor oil until oil just appears
at the bottom of each transaxles' top port
(approximately 2 quarts per transaxle, 4 quarts
total). Install the top port plug into each transaxle
as the oil level reaches the port.
11. Install and torque the top port plugs to 180 in./lbs.
12. Continue to fill the transaxles through the
expansion tank until the FULL COLD line is
reached (this will take approximately 23 additional
ounces).
13. Reinstall the expansion tank cap by hand. Be
careful to not overtighten.
48
LUBRICATION

Transmission Purging

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:
• Noisy operation.
• Lack of power or drive after short term operation.
• High operation temperature and excessive
expansion of oil.
• Shortened component life.
Before starting, make sure the oil tank is at the proper
oil level. If not, fill to the specifications outlined above.
The following procedures are best performed with the
vehicle drive wheels off the ground, then repeated
under normal operating conditions.
See Moving Machine By Hand in the Operation
section for bypass linkage adjustments.
• Disengage the brake if activated.
• With the bypass linkage 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 linkage 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 hydraulic drive operates at normal noise
levels and moves smoothly forward and reverse at
normal speeds, the hydraulic drive 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.