SENR3921
8 Page, UHE
NO. COMPONENT NO. COMPONENT
1 STEERING CYLINDER 26 SWING CYLINDER RELIEF VALVE
2 ATTACHMENT CROSSOVER RELIEF VAVLE 27 L.H. STABILIZER CYLINDER
3 HAND METERING UNIT 28 ATTACHMENT EXTENDABLE STICK CYLINDER
4 HMU INLET CHECK VALVE 29 BACKHOE CONTROL VALVE
5 LIFT CYLINDERS 30 RETURN RESTRICTION VALVE
6 TILT CYLINDER 31 ATTACHMENT EXT. STICK CONTROL VALVE
7 ATTACHMENT CLAM CYLINDERS 32 L.H. STABILIZER CONTROL VALVE
8 SIDESHIFT LOCK CYLINDER 33 STICK CONTROL VALVE
9 LOADER CONTROL VALVE 34 BUCKET CONTROL VALVE
11 STEERING PRIORITY VALVE 35 SWING CONTROL VALVE
12 ATTACHMENT CLAM CONTROL VALVE 36 BOOM CONTROL VALVE
13 TILT CONTROL VALVE 37 R.H. STABILIZER CONTROL VALVE
14 LIFT CONTROL VALVE 38 ATTACHMENT CONTROL VALVE
15 PUMP 41 LINE RELIEF VALVE (13 000 kPa)
16
SIDESHIFT LOCK VALVE 42 LINE RELIEF VALVE (31 000 kPa)
17 HYDRAULIC TANK AND OIL FILTERS 43 LINE RELIEF VALVE (22 000 kPa)
18 OIL COOLER BYPASS VALVE 44 LINE RELIEF VALVE (24 200 kPa)
19 OIL COOLER 45 LINE RELIEF VALVE (20 000 kPa)
20
R.H. STABILIZER CYLINDER
46 MAKEUP VALVE
21 BOOM CYLINDERS 47 ORIFICE CHECK VALVE
22 L.H. SWING CYLINDER 48 STABILIZER LOCK VALVE
23 R.H. SWING CYLINDER 49 ATTACHMENT CHECK VALVE
24
BUCKET CYLINDER
50 ATTACHMENT CHECK VALVE
25 STICK CYLINDER 52 ORIFICE CONNECTER (TWO)
438 HYDRAULIC SYSTEM SCHEMATIC
TEST POINT PRESSURE TAP
A PUMP PRESSURE
B
SIGNAL PRESSURE
©
1988 Caterpillar
All Rights Reserved
Printed in U.S.A.
SENR3921
April 1988
438 Backhoe Loader
Hydraulic System
3DJ1-UP
A) Continued on other side
B) Continued on other side
C) Continued on other side
D) Continued on other side
E)Continuedonotherside
A) Continued on other side
B) Continued on other side
C) Continued on other side
D) Continued on other side
E) Continued on other side
SENR3921
8 Page, UHE
