Shaft Seals - Simplicity 1691682 Service & Repair Manual

7 Transmission Repair
7D Sauer-Sundstrand BDU-10L-258

Shaft Seals

Lip type seals are used on the input shaft, thru shaft, out-
put shaft, and displacement control shaft of the Series 70
transmissions and pumps. These seals can be replaced
without major disassembly of the unit. However, replace-
ment of the seals generally requires removal of the trans-
mission or pump from the machine.
To replace the pump input shaft seal:
1. Remove the retaining ring from the housing.
2. Carefully pull the seal out of the housing bore. A
"hook" type tool may be used to grasp the seal and
pull it out, or a slide hammer type puller may be used
to remove the seal. Care must be taken so as not to
damage the housing bore, shaft sealing surface, or
bearing. Once removed, the seal is not reusable.
NOTE: Once the pump input shaft seal is removed, the
pump block spring may push the shaft partially out of the
housing. Do not attempt to pull the shaft out of the hous-
ing. Internal parts could move out of alignment or fall into
the transmission, requiring major disassembly of the unit.
3. Inspect the sealing area on the shaft for rust, wear, or
contamination. Polish the sealing area on the shaft if
necessary.
INSTALLATION
4. Lubricate the new seal with petroleum jelly.
5. Wrap the spline or key end of shaft with thin plastic to
prevent damage to the seal lip during installation.
6. Slide the seal over the shaft and press it into the
housing bore. Be careful not to damage seal.
7. Install the seal retaining ring in the housing.
The thru shaft, output shaft, and displacement control
shaft seals may be replaced by following a similar proce-
dure. These seals are not held in position by a retaining
ring. The following are the positions of the seals in the
center section or housing. Motor output shaft .11"
(2.79mm), and the Pump Control Shaft is flush to bot-
tomed in the bore.
Figure D-5. Retaining Ring Removal
Figure D-6. Lip Seal Removal
Figure D-7. Lip Seal Installation
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