CHASSIS AR 3904358 - Caterpillar

Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the attachments have been lowered, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide", for tools and supplies suitable to collect and contain fluids in Caterpillar machines.Dispose of all fluids according to local regulations and mandates.
Table 1
Required Tools
Tool Part Number Description Qty
A 8T-0860 Pressure Gauge
0 to 40000 kPa (0 to 8700 psi) 1
6V-4144 Quick Connect Coupler 1
B 177-7860 Hose As 1
6V-4142 Fitting 2
6V-4143 Quick Connect Coupler 2
C 6V-3966 Fitting As 1
D 8J-7844 Reducing Bushing 1
Table 2
Optional Tools(1)
Tool Part Number Description Qty
E(2) 198-4234 Digital Indicator 1
F(2) 198-4236 Adapter Cable As 2
G 198-4238 Pressure Sensor Gp
0 to 35000 kPa (0 to 5000 psi) 1
(1) The optional tools can be used to replace the analog pressure gauges in the required tool list.
(2) Tool (E), Tool (F), Tool (G) are part of the 198-4240 Digital Pressure Indicator Gp.Note: The illustrations in the following procedure show the Water Delivery System installed on a 777F Off-Highway Truck.
Drive the machine to a smooth, horizontal surface.
Place the transmission gear selector in the PARK position.
Apply the brakes and shut down the engine.
Turn the steering wheel several times in order to release any residual pressure from the steering hydraulic system.
Place blocks in front of the rear wheels and behind the rear wheels.
Push the button for the pressure release on the top of the breaker relief valve. The breaker relief valve is located on the top of the steering hydraulic tank.
Illustration 1 g02764056
Locate steering check and relief valve (1) on the machine frame behind the right front suspension cylinder. Remove steering pump oil pressure switch (2).
Install Tool (D) at the location of steering pump oil pressure switch. Connect Tool (C) to Tool (D).
Assemble Tool (A) and Tool (B). Connect Tool (A) to Tool (B).
Connect Tool (B) to Tool (C).
Start the engine. Run the engine at high idle.
Place the transmission gear selector in the NEUTRAL position. Note: When the transmission gear selector is in the PARK position, friction from the wheel brakes will not allow the secondary steering system to turn the wheels all the way to the cylinder stops.
Turn the steering wheel to the right until the steering cylinder stop is reached. Continue turning the steering wheel against the stop.