STEERING PUMP
The steering/brake pump is mounted on the rear of the
hoist system pump. The drive shaft mates with an
internally splined coupling inside the hoist pump when
the pump is bolted in place.
The pump is a pressure compensated piston type with
system operating pressure controlled by an unloader
valve. The pressure compensator is adjusted to 3325
psi (22.9 MPa). The pump mounted unloader valve
maintains system pressure between 2750 psi (19.0
MPa) and 3025 psi (20.9 MPa).
Oil flow from the pump is routed through a high pres-
sure filter then to the bleeddown manifold valve where
the flow is directed to the steering circuit (accumula-
tors, flow amplifier, etc.) and to the brake apply system
components mounted in the hydraulic components
cabinet behind the cab.
Operation
The driveshaft (35, Figure 4-10) runs through the cen-
terline of pump housing (37) and valve plate (48). The
cylinder barrel (45) is splined to the drive shaft.
A ball bearing (33) supports the outboard end of the
driveshaft and a bushing type bearing (47) supports the
inboard end. The pump cylinder barrel is carried in a
polymerous (journal type) bearing (41).
The valve plate has two crescent shaped ports (inlet
and outlet). Pumping pistons (44) in the cylinder barrel
are held against a swashblock (28) by a shoe retainer
(17). The shoe retainer is held in position by the fulcrum
ball (40) which is forced outward by retainer springs
(13). The springs act against the pump cylinder barrel
(45) forcing it against the valve plate while also forcing
the piston shoes against the swashblock.
The semi-cylindrical shaped swashblock limits the pis-
ton stroke and can be swiveled in arc shaped saddle
bearings (21). The cradle is swiveled by the control
piston (14).
High Altitude Operation
The steering pump on later model trucks incorporates
an adjustable stroke control device (25, Figure 4-10).
If the truck is operating at high altitude locations (10,
000 feet (3,050 meters) above sea level or greater), it
may be necessary to adjust the pump stroke to reduce
oil flow to eliminate pump cavitation problems.
L4-16
Steering Circuit
L04031
Summary of Contents for 930E-2
Page 1: ......
Page 2: ......
Page 4: ...NOTES ...
Page 8: ...KOMATSU MODEL 930E Dump Truck A 4 Introduction A00017 03 01 ...
Page 10: ...NOTES A1 2 Index A01001 2 94 ...
Page 12: ...930E MAJOR COMPONENTS A2 2 Major Component Description A02055 ...
Page 35: ...START HERE Walk Around Inspection A03017 General Safety and Operating Instructions A3 21 ...
Page 46: ...NOTES A3 32 General Safety and Operating Instructions A03017 ...
Page 78: ...NOTES B1 2 Index B01016 ...
Page 88: ...NOTES B3 6 Dump Body B03013 03 01 ...
Page 92: ...NOTES B4 4 Fuel Tank B04015 ...
Page 94: ...NOTES C1 2 Index C01021 03 01 ...
Page 118: ...NOTES C5 6 Air Filtration System C05013 5 98 ...
Page 126: ...NOTES D2 6 24VDC Electric Supply System D02018 ...
Page 142: ...NOTES D3 16 24VDC System Components D03019 04 01 ...
Page 146: ...FIGURE 2 1 PROPULSION SYSTEM DIAGRAM E2 2 Electrical Propulsion System Components E02014 3 01 ...
Page 196: ...NOTES E2 52 Electrical Propulsion System Components E02014 3 01 ...
Page 240: ...NOTES E3 44 AC Drive System Electrical Checkout Procedure 3 01 E03015 Release 17 Software ...
Page 242: ...NOTES G1 2 Index G01017 ...
Page 250: ...NOTES G2 8 Tires and Rims G02015 ...
Page 274: ...NOTES H1 2 Index H01013 04 01 ...
Page 282: ...NOTES H2 8 Front Suspensions H02013 2 01 ...
Page 288: ...NOTES H3 6 Rear Suspensions H03013 ...
Page 334: ...NOTES J3 32 Brake Circuit Component Service J03019 1 99 ...
Page 378: ...NOTES L2 8 Hydraulic System L02028 ...
Page 401: ...FIGURE 4 5 FLOW AMPLIFIER VALVE L04031 Steering Circuit L4 7 ...
Page 403: ...FIGURE 4 6 FLOW AMPLIFIER NO STEER L04031 Steering Circuit L4 9 ...
Page 405: ...FIGURE 4 7 FLOW AMPLIFIER LEFT STEER L04031 Steering Circuit L4 11 ...
Page 407: ...FIGURE 4 8 FLOW AMPLIFIER RIGHT STEER L04031 Steering Circuit L4 13 ...
Page 409: ...FIGURE 4 9 FLOW AMPLIFIER NO STEER EXTERNAL SHOCK LOAD L04031 Steering Circuit L4 15 ...
Page 414: ...NOTES L4 20 Steering Circuit L04031 ...
Page 422: ...NOTES L5 8 Steering Control Unit L05021 ...
Page 429: ...L06021 Steering Circuit Component Repair L6 7 ...
Page 450: ...NOTES L6 28 Steering Circuit Component Repair L06021 ...
Page 466: ...NOTES L7 16 Hoist Circuit L07023 ...
Page 492: ...NOTES L9 6 Hydraulic System Filters L09008 ...
Page 504: ...NOTES L10 12 Hydraulic Check out Procedure L10012 ...
Page 508: ...NOTES M1 2 Index M01034 03 01 ...
Page 518: ...NOTES M2 3 10 Ansul Checkfire Electric Detection and Actuation System M02003 ...
Page 524: ...NOTES M5 4 Wiggins Quick Fill Fuel System M05002 10 96 ...
Page 532: ...NOTES M8 8 Special Tools M08012 9 99 ...
Page 560: ...NOTES M9 28 Air Conditioning System M09010 6 97 for HFC 134a Refrigerant ...
Page 618: ...M20 20 Payload Meter II M20007 10 00 ...
Page 619: ...M20007 10 00 Payload Meter II M20 21 ...
Page 627: ...M20007 10 00 Payload Meter II M20 29 ...
Page 634: ...NOTES N1 2 Index N01020 03 01 ...
Page 654: ...NOTES N3 6 Cab Components N03011 7 98 ...
Page 660: ...NOTES N4 6 Operator Comfort N04020 ...
Page 686: ...NOTES N5 26 Operator Cab Controls N05044 ...
Page 688: ...NOTES P1 2 Index P01024 ...
Page 691: ...P02034 Lubrication and Service P2 3 ...
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Page 737: ...NOTES R1 2 930E Schematics R01048 with Cummins QSK60 Series Engine ...
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