Chevrolet 10 Series 1970 Service Manual page 314

BRAKES 5-76
NUT, VALVE STEM
" O " RING, STEM PISTON
PISTON, VALVE STEM
VALVE BODY
" O " RING, STEM FRONT
Fig. 126— Push P ull C o n tro l V a lv e
IN VER SIO N VALVE (Fig. 127)
Removal
1. B lock and hold v e h icle by means other than a ir
brakes.
2. Drain s e rv ic e and isolated r e s e r v o ir supplies.
3. D isconnect a ir lin es fro m inversion valve.
4. Loosen va lve mounting nut and rem ove valve.
Disassembly
1. R em ove cap nut with sealin g ring, rem ove sealing
ring fro m cap nut.
2. R em ove inlet va lve spring and inlet va lve.
3. Turn va lve o v e r and rem ove
diaphragm cap screw with lock w asher, then dia­
phragm washer and diaphragm .
4. W ith a p a ir o f #1 T ru a rc p lie rs , rem ove reta in er
ring.
5. R em ove c o v e r plate
6. R em ove piston with grom m ets.
7. Rem ove piston grom m ets.
Cleaning and Inspection
1. Wash all m etal p arts in a good cleaning solvent.
Rubber parts should be wiped clean.
2. Inspect all parts fo r e x c e s s iv e w ear or d eterioration .
3. Check springs fo r crack s, corrosion , o r distortion.
4. Inspect piston and its exhaust seat, body b ores and
inlet va lve seat fo r nicks o r bu rrs.
5. R eplace all parts not considered serv ic e a b le during
these inspections.
Assembly
NOTE:
B efo re assem blin g the v a lve, lubricate
the piston, grom m ets and body b ores with a
B arium -B ase grea se.
1. Install piston grom m ets on piston.
2. Install piston with grom m ets in valve body.
3. Position piston sprin gs,
rin g in the piston in that ord er. P r e s s the c o v e r and
reta in er down and with a p a ir of T ru a rc #1 p lie r s ,
snap the ring into the body groove.
4. Install the diaphragm and diaphragm washer and
secu re with cap screw .
CAP, VALVE END
GASKET-
NUT, VALVE MOUNTING
" O " RING, STEM CENTER
VALVE STEM
exhaust check va lve
and two (2) piston springs.
c o v e r plate and reta in er
5. Turn in version valve o v e r and position inlet and
exhaust va lve in its bore.
6. P la ce spring down over inlet valve.
7. In stall sealing ring on cap nut, install cap nut with
sealing ring and tighten secu rely.
8. Mounting nut and lock w asher are installed when
va lve is mounted on veh icle.
Installation
1. Install mounting nut.
2. Connect a ir lines.
TRAILER EMERGENCY CONTROL VALVE (Fig. 128)
The va lve is a dash mounted push-pull type that p ro ­
vid es fo r manual o r automatic control of the tr a ile r
brakes in case of a ir pressu re loss on the tra cto r. It is
connected between the tra ctor a ir r e s e r v o ir and the
s e r v ic e line to the tr a ile r .
1 2 7 — In v e r s io n V a l v e
1. S u p p ly P o rt
2 . I n l e t a n d E x h a u s t
V a l v e S p r in g
3 . B o dy
4 . C o n t r o l P o rts ( 3 )
5 . P is to n S p rin g s
6 . R e t a in e r R in g
7 . E x h a u s t D i a p h r a g m
8 . C a p N u t
9 . S e a l R in g
10. M o u n t i n g N u t
I I . L o c k W a s h e r
12. I n l e t a n d E x h a u s t
V a l v e
1 3. D e l i v e r y P o rts ( 2 )
14. P is to n G r o m m e t
( S m a l l )
1 5. P is to n
1 6. P is to n G r o m m e t
( L a r g e )
1 7. C o v e r P l a t e
18. D ia p h r a g m W a s h e r
19. C a p S c r e w
CHEVROLET TRUCK SERVICE MANUAL