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1
Figure 1 – Bendix
®
R-12DC
®
Relay Valve Exploded View
*Crack Pressure is the amount of control
pressure required by the valve to initiate
air delivery. For Crack pressures other
than 4 psi, a differential spring is used
in the assembly to produce the required
valve response.
(Models designed to have a 4 psi crack
pressure do not require a differential spring.)
Primary Control
Port 1/4 NPT
Secondary
Control Port
1/4 NPT
Cap Screw
Torx
®
Screw
Differential Spring
(Controls Crack Pressure*)
(Not required for Most
Models.
See Below
.)
Vertical
Delivery
Ports
Supply Port
Horizontal Delivery
Ports
Differential Springs
BENDIX
®
R-12DC
®
RELAY VALVE MAJOR MAINTENANCE KIT
Kit Contents
Item No.
Description
Qty.
1
Valve Spring
1
2
Check Valve Guide
1
3
Check Valve
1
4
O-Ring
1
5
O-Ring
1
6
O-Ring
1
7
Inlet & Exhaust Valve
1
8
Valve Retainer
1
9
Spring
1
10
O-Ring
1
11
O-Ring
1
12
Exhaust Cover
1
13
Retaining Ring
1
14
Lubricant (Not Shown)
1
6
7
8
2
3
4
5
1
9
13
12
11
10
Valve
Cover
Double
Check
Cover
Relay Piston
Valve Body