4
TRACTOR
PROTECTION
VALVE
TEE FITTING
EXISTING REAR
AXLE SERVICE
DELIVERY LINE
REAR
AXLE
SERVICE
RELAY
VALVE
REAR AXLE
SERVICE
RESERVOIR
TEE FITTING
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
certain all components and systems are restored to
their proper operating condition.
INSTALLATION
(REFER TO FIGURE 6)
1. The vehicle being fitted with a BP-1
™
rear brake
proportioning valve must be equipped with a rear axle
service relay valve. It cannot be installed on a vehicle
utilizing a quick release valve system without a relay
valve.
2. For vehicles equipped with a front axle service ratio or
limiting valve (such as the Bendix
®
LQ-4
™
valve) it must
be removed and replaced by the BP-1
™
front valve
provided in kit #209924.
Caution:
The front and rear BP-1
™
valves are not
interchangeable. They are identified with a metal
tag stamped ‘BP-1 Front’ or ‘BP-1 Rear’ attached
to one of the cap screws on the cover.
3. Mount the BP-1
™
rear valve and the TR-3
™
inversion valve
in a protected area that is convenient to the service line
between the brake valve and the relay valve.
4. Install the BP-1
™
rear valve into the service line from the
brake valve. Connect the delivery line from the brake
valve to the supply port of the BP-1
™
valve and the delivery
port of the BP-1
™
valve to the control port on the relay
valve.
5. Connect the TR-3
™
inversion valve as follows. Tee the
control port to the delivery of the trailer supply valve,
the supply port to the supply line of the brake valve, and
connect the delivery port to the control port of the BP-1
™
valve.
Note:
If vehicle does not have a front axle ratio or limiting
valve, proceed to “Operational Checks”. If vehicle
has a front axle ratio or limiting valve, continue with
Step 6.
6. Remove the existing front axle ratio or limiting valve and
replace it with the BP-1
™
front valve. Connect the front
axle brake valve delivery line to the supply port of the
BP-1
™
valve, the delivery port of the BP-1
™
valve to the
front axle actuators, and the control port of the BP-1
™
valve to the delivery of the TR-3
™
inversion valve.
OPERATIONAL CHECKS
After components have been installed and all connections
made, perform the following checks.
1. With the trailer supply valve pulled out (bobtail running
position) install two air gauges in the service system;
one at an actuator on the front axle and one at an actuator
on a rear axle.
Key No.
Qty.
Description
1
1
BP-1
™
(Rear) Valve
2
1
TR-3
™
Inversion Valve
3
1
BP-1
™
(Front) Valve
FIGURE 6
TYPICAL INSTALLATION SCHEMATIC OF BRAKE PROPORTIONING SYSTEM
Ê
Ì
Ë
TRACTOR PROTECTION
CONTROL VALVE
BRAKE VALVE
EXISTING
LINE
TEE FITTING
REPLACES FRONT
AXLE LIMITING
VALVE
EXISTING FRONT
AXLE SERVICE
DELIVERY LINE
KEY
C-CONTROL
D-DELIVERY
S-SUPPLY
