4 - 52
S-40 • S-45
Part No. 102521
October 2013
Section 4 • Repair Procedures
MANIFOLDS
7-14
Valve Adjustments, 4WD
Drive Manifold
How to Adjust the Hot Oil Shuttle
Relief Valve
Note: The pressure differential between the charge
pump relief valve (located in the drive pump) and
the hot oil shuttle relief valve (located in the drive
manifold) is necessary to return hot oil from the
closed loop drive circuit to the hydraulic tank for
cooling. This pressure differential must be
maintained at 40 psi / 14.5 bar.
Note: The following procedure will require two
people.
1 Open the engine side turntable cover and
connect a 0 to 600 psi / 0 to 41 bar pressure
gauge to the diagnostic nipple on the drive
pump.
2 Start the engine from the platform controls and
allow the engine to run at high idle. Note the
pressure reading on the pressure gauge.
3 Turn the engine off and connect a
0 to 600 psi / 0 to 41 bar pressure gauge to the
diagnostic nipple located on the drive manifold.
4 Start the engine from the platform controls and
drive the machine slowly in the forward
direction. Note the pressure reading on the
pressure gauge.
5 Turn the engine off, and remove the hot oil
shuttle relief valve cap (item HH). Adjust the
internal hex socket clockwise to increase the
pressure or counterclockwise to decrease the
pressure. Install the valve cap.
(before serial no. 7569)
5 Turn the engine off, and remove the hot oil
shuttle relief valve cap (item JA). Adjust the
internal hex socket clockwise to increase the
pressure or counterclockwise to decrease the
pressure. Install the valve cap.
(from serial no. 7569 to 15822)
5 Turn the engine off, and remove the hot oil
shuttle relief valve cap (item KA). Adjust the
internal hex socket clockwise to increase the
pressure or counterclockwise to decrease the
pressure. Install the valve cap.
(from serial no. 15823)
6 Repeat steps 4 and 5 until the pressure reading
on the guage is 40 psi / 2.8 bar less than the
pressure reading at the pump.
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