HYDRAULIC SYSTEM
RT765E-2 SERVICE MANUAL
2-26
Published 9-04-2014, Control # 422-08
Procedure E - Charge Air Cooler Valve Relief
Pressure
1.
With engine off, disconnect hose at port “CF2” at the
brake charge/CAC fan motor supply valve Figure 2-9;
cap and plug all openings.
2.
Install pressure check diagnostic quick disconnect with
gauge onto test nipple at brake charge/CAC fan motor
supply valve test port.
3.
Start engine and operate at full RPM. Adjust “CAC Fan
Relief Valve” to 1000 psi +50/-0 (6.9 MPa +.4/-0).
4.
Remove pressure gauge from test port, and reconnect
hose to port “CF2”.
Procedure F - Brake Dual Accumulator
Charge Valve Pressure Limits
1.
With the engine off, discharge all of the pressurized oil
stored in the accumulators by depressing the service
brake pedal on the cab floor 8-10 times.
2.
Install a pressure gauge at the service brake dual
accumulator charge valve “A1” pressure test port (1,
Figure 2-10).
3.
Start the engine. The charging valve will immediately
start to charge the accumulators. Watch the pressure
gauge. The high charge limit pressure should read
2320 psi +72/-145 (17.4 MPa +0.5/-145) when the valve
stops charging. The accumulator charge valve is non-
adjustable.
4.
With the engine running, bleed off the hydraulic pressure
stored in the accumulators by pushing the service brake
pedal on the cab floor until the gauge reads about
1950 psi (13.4 MPa). Listen to hear when the service
brake dual accumulator charge valve starts to recharge.
Push the service brake pedal once more; the valve
should start to recharge. Watch the pressure gauge. The
low charge limit should be 1950 psi ±145 (13.4 MPa
±1.0) when the valve starts to recharge. The
accumulator charge valve is non-adjustable.
5.
Turn engine off. Remove all of the fittings in the tank port
on the service brake dual accumulator charge valve and
plug the tee.
Procedure G - Accumulator Pre-Charge
Pressure
1.
With the engine off, discharge all of the pressurized oil
stored in the accumulators by depressing the service
brake pedal on the cab floor several times. Remove the
g a s v a l v e g u a r d a n d c a p o n t h e a c c u m u l a t o r
Figure 2-11.
2.
Before attaching the gas charging assembly Figure 2-11
onto the accumulator gas valve, back the gas chuck “T”
handle all the way out (counterclockwise).
Test Port
FIGURE 2-9
7798
CF1 Port
Adjustable Inlet
Relief Valve
CF2 Port
Adjustable
CAC Fan
Relief Valve
FIGURE 2-10
1
7884
Reference Only