Bendix Commercial Vehicle Systems RV-3 PRESSURE REDUCING VALVE 3/04 - Manual (Page 2)

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underside of the piston. When air pressure on the piston
overcomes the spring force, the piston moves and forces
the inlet valve on its seat, closing off the supply of air. The
exhaust remains closed. If air pressure in the delivery line
drops, the spring force on the piston overcomes the air
pressure. Subsequent piston movement will unseat the
inlet valve, allowing additional air pressure into the delivery
line. If pressure in the delivery line exceeds the pressure
setting of the valve, the force exerted by the air pressure
will be greater than the spring force. The piston will move
away from the exhaust valve, permitting air to fl ow past the
exhaust valve, through the hollow piston stem and out the
exhaust port. The inlet valve remains seated.
OPERATING & LEAKAGE TESTS
OPERATING
Connect an accurate test gauge in the supply and delivery
lines of the Bendix
® RV-3 ™ valve. Make certain that supply
air pressure is at the vehicle manufacturer’s recommended
level (applied at a rate of 100 psi/sec). Delivery pressure
should be within ± 5 psi of the delivery pressure specifi ed
for the RV-3 valve. If not, the valve should be replaced. If
the valve meets this operating test, proceed to the leakage
tests. Do not remove the gauges at this time.
LEAKAGE
With supply pressure at the level recommended by the
vehicle manufacturer, apply a soap solution to the 1/8”
N.P.T. plug, around the supply port cap nut, and to the
exhaust port. Leakage should not exceed 100 SCCM (or a
1” diameter bubble in 5 seconds). If leakage is excessive,
the valve should be replaced and the operating and leakage
tests performed at the time of replacement. Proceed to the
“Removal and Installation” instructions. This completes the
operation and leakage tests, and the test gauges should
be removed
.
REMOVAL & INSTALLATION
REMOVAL
1. Hold the vehicle on a level surface by means other
than the air brakes.
2. Remove all air pressure from all reservoirs.
3. Identify, mark and then disconnect all air lines at tached
to the valves.
4. Remove the valve.
INSTALLATION
1. Inspect and clean all air lines that connect to the valve.
2. Clean the vehicle valve mounting area and mount the
valve.
3. Reconnect the air lines according to the identifi ca tion
marks made during removal.
PREVENTIVE MAINTENANCE
Important: Review the Bendix Warranty Policy before
performing any intrusive maintenance procedures. A
warranty may be voided if intrusive maintenance is
performed during the warranty period.
No two vehicles operate under identical conditions, as
a result, maintenance intervals may vary. Experience is
a valuable guide in determining the best maintenance
interval for air brake system components. At a minimum,
the Bendix RV-3 valve should be inspected every 6 months
or 1500 operating hours, whichever comes fi rst, for proper
operation. Should the RV-3 valve not meet the elements
of the operational tests noted in this document, further
investigation and service of the valve may be required.