Changing The Transaxle Fluid; Every 500 Hours; Replacing The Spark Plug - Kubota Z412KW Operator's Manual

EVERY 400 HOURS
4. After the oil has drained, inspect all parts for
excessive wear or damage. Replace if necessary.
5. Wipe off the filter base surface and apply a film of
new oil to the gasket of the new replacement filter.
6. Install the new filter by hand and turn 3/4 to 1 full
turn after the filter gasket contacts the filter base
surface.
(1) Transaxle
(2) Transaxle oil filter
(3) Filter guard
(4) Hex flange head bolt
(5) Breather port plug
7. Reinstall the filter guard (3) with 3 hex head bolts
(4). Tighten bolts (4) to 7.35 N⋅m (5.42 lbf⋅ft)
securely.
8. Repeat steps 2 through 7 on the opposite side
transaxle drive.
9. Drain the old oil filters of all free flowing oil prior to
disposal. Place the used oil in appropriate
containers and deliver to an approved recycling
collection facility.
10. Remove the breather port plug (5) from the left side
and right side transaxles prior to filling with oil. This
will allow the transaxles to vent during oil fill.
11. Remove the cap from the transaxle fluid tank
located on the machine frame.
12. Fill with 20W-50 motor oil until oil appears just at
the bottom of the breather port. Install the breather
port plug (5) into the transaxle. Tighten the plug (5)
to 20.34 N⋅m (15.0 lbf⋅ft).
Z412KW,Z422KW,Z422KWT,Z411KW,Z421KW,Z421KWT
(A) Front
(B) Oil level
13. Continue to fill the transaxles through the transaxle
fluid tank until the "FULL COLD" line is reached on
the transaxle fluid tank.
14. Reinstall the transaxle fluid tank cap by hand. Be
careful not to overtighten.
15. Proceed to the purge procedure.
Purging procedures
Due to the effects air has on efficiency in hydrostatic
drive applications, it is critical to purge it from the
system.
Air creates inefficiency because its compression and
expansion rate is higher than the one of the oil
approved for use in hydrostatic drive systems.
These purge procedures should be performed anytime
a hydrostatic system has been opened to facilitate
maintenance or the oil has been changed.
The resulting symptoms in hydrostatic systems may be:
1. Noisy operation.
2. Lack of power or drive after short-term operation.
3. High operation temperature
expansion of oil.
Before starting, make sure the transaxle oil is at the
proper oil level. If it is not, fill to the specifications
outlined in this manual.
The following procedures are best performed with the
machine drive wheels off the ground. Then, repeat
under normal operating conditions. If this is not
possible, then the procedure should be performed in an
open area free of any objects or bystanders.
1. Disengage the brake if activated.
2. With the bypass valve open and the engine
running, slowly move the motion control levers in
both forward and rearward directions (5 or 6 times).
3. With the bypass valve closed and the engine
running, slowly move the motion control levers in
both forward and rearward directions (5 to 6 times).
Check the oil level, and add oil as required after
stopping the engine.
4. 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 rearward at normal
speed, then the transaxle is considered purged.

2. Changing the transaxle fluid

(See Replacing the transaxle oil filter on page 66.)

EVERY 500 HOURS

1. Replacing the spark plug

(See Checking the spark plug on page 61.)
PERIODIC SERVICE
and excessive
67