3. Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Useonly the proper tools and observe
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems,make certainto drain theair pressure from
all reservoirs before beginning ANY work on the
vehicle. If the vehicle is equipped with an AD-IS™
air dryer system or a dryer reservoir module, be
sure to drain the purge reservoir.
5. Following the vehicle manufacturer’s
recommendedprocedures, deactivate the electrical
system in a manner that safely removes all
electrical power from the vehicle.
6. Never exceed manufacturer’s recommended
pressures.
7. Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove a
component or plug unless you are certain all
system pressure has been depleted.
8. Use only genuine Bendix®replacement parts,
components and kits. Replacement hardware,
tubing, hose, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically for such applications and
systems.
9. Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifically stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certainallcomponentsandsystemsarerestoredto
their proper operating condition.
PREVENTIVE MAINTENANCE
Important: Review the Bendix Warranty Policy before
performinganyintrusivemaintenanceprocedures.Awarranty
maybevoidedifintrusivemaintenanceisperformedduring
thewarrantyperiod.
No two vehicles operate under identical conditions, as a
result, maintenance intervals may vary. Experience is a
valuableguide in determining thebestmaintenanceinterval
forairbrakesystemcomponents.Ataminimum,theQRN-2™
valveshouldbeinspectedevery12monthsor3600operating
hours,whichever comes first,for proper operation.Should
theQRN-2™valvenotmeettheelementsof the operational
testsnotedinthisdocument,furtherinvestigationandservice
ofthevalvemayberequired.
SERVICE CHECKS
1. Remove any accumulated contaminants. Visually
inspectthe valve’s exterior forcracks, gouges, orother
physicaldamage. Replace the valveifphysicaldamage
is excessive.
2. Inspect all air lines connected to the valve for signs of
wearor physicaldamage. Repair/replaceas necessary.
3. Test air linefittingsforexcessive leakage and tighten or
replace as necessary.
OPERATIONAL AND LEAKAGE TESTS
1. Block the vehicle’s wheels and fully charge the air
system.
2. Applyandreleasetheservicebrakes several times and
check for prompt response of the brakes at the
appropriatewheels.
3. Withtheair system fully charged,apply a soap solution
to the QRN-2™valve exhaust port. Leakage of a 1"
bubble in 5 seconds is permissible.
4. Makeandholda full brake applicationandagainapplya
soapsolution to the QRN-2™valve exhaust. Leakageof
a 1" bubble in 3 seconds is permissible.
5. Withthebrakesstillapplied,applyasoapsolutionaround
thevalve where theexhaust cover meetsthe body. No
leakage at this point is permitted.
If the valve does not function as described, or if leakage is
excessive, replace it at any authorized parts outlet.
REMOVAL
1. Identify and mark or label all air lines and their
connectionstotheQRN-2™valve. Thendisconnectthe
air lines.
2. RemovetheQRN-2™valvefrom the vehicle. Retain the
mountinghardware.
INSTALLATION
1. Install the QRN-2™valve on the vehicle using the
mountinghardwaresavedduringremoval.
2. Reconnectallairlinestothevalveusing theidentification
madeduringremoval.
3. Test all air fittings for excessive leakage and tighten as
needed. NOTE: MAXIMUMTORQUEFORFITTINGS
IS10FT.LBS. PerformOPERATIONALANDLEAKAGE
TESTSbeforeplacingthe vehicle back into service.
NOTE: THERE ARE NO DISASSEMBLY/ASSEMBLY
PROCEDURES FOR THE QRN-2™VALVE. IT IS A
REPLACE ITEM. IF A VALVE DOES NOT MEET THE
OPERATIONALAND LEAKAGE TESTS, IT SHOULD BE
REPLACEDATANYAUTHORIZEDPARTSOUTLET.
