7 - 25
7 Transmission Repair
7B Sauer-Sundstrand BDU-21L-207
RECONDITIONING AND REPLACEMENT OF PARTS
After disassembly,all parts should be thoroughly cleaned
in a suitable solvent.
1. Inspect all parts for damage, nicks or unusual wear
patterns. Replace all parts having unusual, excessive
wear or discoloration.
2. Inspect the sealing surfaces, bearing surfaces, and
shaft splines. Polish the sealing areas on the shafts if
necessary. Replace any worn or damaged parts.
The running surfaces of the cylinder blocks MUST be flat
and free from scratches. If scratches or wear are found
on the running surface of the cylinder block or center
section, polish or replace the parts. When polishing
these surfaces, up to 0.0004 in. may be removed. If this
is not sufficient to obtain a flat surface free of scratches,
the part should be replaced.
ASSEMBLY PROCEDURES
1. Clean and lightly oil parts prior to assembly of the
BDU transmission.
Be sure to torque all threaded parts to the recommended
torque levels.
2. Replace all o-rings, gaskets and shaft seals.
CAUTION: Most parts have critical high tolerance
surfaces. Care must be exercised to prevent
damage to these surfaces during assembly.
Protect exposed surfaces, openings, and ports
from damage or foreign material.
3. Install the displacement control shaft.
4. Install the pump shaft assembly into the housing.
5. Install the bearing spacer washer.
6. Install the lip seal and retaining ring as described in
the minor repair section.
7. Install the slot guide block onto the displacement con-
trol shaft.
8. Install the swashplate into the housing. The slot on
the swashplate must engage the slot guide block on
the displacement control shaft. Use a tool such as a
screw driver or scribe to hold the guide block in posi-
tion while installing the swashplate.
NOTE:As a product improvement, since July 1, 1993 the
BDU-21 thrust bearings for both the motor and pump are
now the same. They are not interchangeable with the old
versions. New housing kits, or new swashplate kits will
be necessary to accommodate new thrust bearings.
Figure B-17. Control Arm Installation
Summary of Contents for 1691766
Page 2: ......
Page 20: ...2 Troubleshooting Notes 2 4 ...
Page 34: ...3 14 3 Maintenance Notes ...
Page 86: ...6 General Repair 6A Steering Front Wheel Repair Notes 6 16 ...
Page 130: ...6 60 6 General Repair 6C Foot Controls Repair ...
Page 188: ...7 46 7 Transmission Repair 7C Hydro Gear 216 3010L ...
Page 240: ...8 20 8 Mower Deck Repair Notes ...