Service Manual
HY13-1521-M2/US Service Manual
General Information Series HB Hydrostatic Transmission
28
Parker Hannifin Corporation
Hydraulic Pump/Motor Division
Greeneville, Tennessee USA
End block assembly
Key factor in the successful
repair is cleanliness. Prior to
assembly make sure all
exposed surfaces are
thoroughly clean and free of
foreign material and
chemicals. Replace all seals,
o-rings, oils and gaskets with
original OEM parts.
Orifice plug is clean
Do not remove the orifice
plug! Make sure the orifice is
free from debris by blowing
low pressure shop air through
orifice to ensure clean
passage.
Install the shock /
check valves
16cc – 280 will have 241
number on the outside of
shock valve
12cc – 240 will have 275
number on the outside of
shock valve
Engage threads manually
hand start several threads to
prevent cross threading.
Torque shock valve to
specifications 480 - 540 in.
lbs.
Torque check valves to 252 –
288 in lbs.
Lube the bypass valve O-ring
and position in bypass port.
Install the bypass valve