caterpillar engine tools

Systems Operation
784C, 785C and 785C HAA Off-Highway Truck/Tractors Air System and Brakes
Air Tank
SMCS - 4272
The primary air tank is located on the right hand platform that is near the cab. The primary air tank
contains pressurized air for control of the following systems and components: the air starting system,
the service brakes, the automatic lubrication system, the horn and the retarder.
The primary air tank contains a relief valve. This relief valve cannot be adjusted.
Shutdown SIS
Previous Screen
Product: TRUCK
Model: 785C TRUCK APX
Configuration: 785C Off-Highway Truck APX00001-UP (MACHINE)
POWERED BY 3512B Engine
Media Number -SENR1494-06 Publication Date -01/08/2004 Date Updated -03/08/2004
i02101743
Illustration 1 g00296875
Primary air tank
Illustration 2 g00908299
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The secondary air tank is located in the compartment that is located behind the cab. A cover must be
removed in order to access the secondary air tank. The secondary air tank contains pressurized air for
the secondary braking circuit.
(S/N: 1HW1-UP)
(S/N: 2PZ1-105)
(S/N: 5AZ1-399)
(S/N: APX1-450)
Secondary air tank
Illustration 3 g01070417
(S/N: 2PZ106-UP)
(S/N: 5AZ400-UP)
(S/N: APX451-UP)
Secondary air tank
Illustration 4 g00672126
Location of the drain valve for the primary air tank
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Each air tank contains a drain valve. The drain valve for the primary air tank is on the primary air
tank. The drain for the secondary air tank is on the right side of the cab.
Illustration 5 g00405338
Location of the drain valve for the secondary air tank
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Tue Jun 28 01:56:00 UTC+0700 2005
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