Bypass Valve; Charge Pump/Assembly Procedures; Major Repair; Disassembly Procedures - Cub Cadet 3000 Series Service Manual

BYPASS VALVE

Remove the bypass valve plug with a 9/16" hex
wrench.
Remove the bypass valve plug, spool and spring from
the transmission center section.
Inspect the valve spool and mating bore in the center
section for damage or foreign material. The spool
must move freely. It is recommended that the o-rings
be replaced.
Retain the valve spring to the valve spool with
petroleum jelly. Install the valve spool, spring and plug
(with o-ring) into the center section. Torque the plug
to 7-10 ft. lbs.
Depress the bypass valve several times to insure that
it operates smoothly and fully closes. The bypass
"button" should extend from the hex plug
approximately 0.22" when fully released (closed).
CHARGE PUMP
ASSEMBLY PROCEDURES
For BDU-21L with implement circuit: Install the
drive pin. Install a new o-ring on each side of the
gerotor assembly and position the gerotor assembly
onto the aligning pins in the same orientation as it
was removed. Install the charge pump shim and the
charge pump cover. Torque the bolts evenly to 18-25
ft. lbs.

MAJOR REPAIR

GENERAL INFORMATION
Major repairs described in the following sections are
for the complete disassembly and reassembly (Major
Repair) of the transmission and will void all product
warranty, unless license to perform said major repairs
was previously obtained from an authorized
representative of Cub Cadet.
Cleanliness is a primary means of assuring
satisfactory life on repaired units. Cleaning parts by
using solvent wash and air drying is usually adequate.
As with any precision equipment, all parts must be
kept free of foreign materials and chemicals.
Protect all exposed sealing surfaces and open
cavities from damage and foreign material. The outer
surfaces should be cleaned before beginning any
repairs.
It is recommended that all O-rings and seals be
replaced. Lightly lubricate all O-rings and seals with a
clean petroleum jelly prior to assembly.
It is recommended that parts requiring replacement
be replaced with the complete assembly (kit) as
shown in the service parts drawings.
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Prior to performing major repairs on the BDU
Hydrostatic Transmission, remove the transmission
from its installed location and remove any external
components such as a cooling fan and input pulley or
frame mounting hardware.
NOTE: Thoroughly clean all exposed surfaces prior to
any further disassembly.
Remove the oil lines (hoses and fittings) so that as
much oil as possible can be drained from the housing.

DISASSEMBLY PROCEDURES

Prior to performing major repairs on the BDU remove
the external components as described in the Minor
Repairs section of this manual. These include the
following:
Using a 6 mm internal hex wrench, remove the eight
screws which retain the center section to the housing.
The internal springs of the pistons should separate
the center section from the housing. Remove the cen-
ter section from the housing.
CAUTION: The cylinder blocks may stick to the
surface of the center section. Exercise caution to
prevent damage to the components.
Remove the gasket and two aligning pins from the
housing. The gasket will not be reusable.
For BDU remove the filter element, filter washer and
spring from the housing.
Remove the pump cylinder block kit from the pump
shaft. Inspect the splines on the shaft and in the pump
block for damage or excessive wear. Check the
pistons and block bores for excessive wear. The
pistons should fit with very little side clearance in the
block bores, but must slide freely.
Remove the pump cylinder block spring and thrust
washer from the pump shaft.
Remove the motor cylinder block kit and shaft
assembly from the housing. Check the pistons and
block bores for excessive wear. The pistons should fit
with very little side clearance in the block bores, but
must slide freely. Inspect the splines for damage or
unusual wear. Replacement of the complete
assembly is recommended if damage or excessive
wear is found.
Remove the motor thrust bearing assembly from the
housing.
18 - 7
Cub Cadet 3000
Bypass Valve
Charge Check Valves
Charge Pump Assembly