Chevrolet 10 Series 1970, Руководство по обслуживанию

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BRAKES 5-55
SPRING
INLET
PORT
CLAMP RING
NUTS AN D
BOLTS
CLAMP
R IN G
N O N PRESSURE
PLATE
► M O U N TIN G BOLTS
YO KE
...
I
581
F ig . 9 8 —A i r Brake C ham ber (C la m p Ring Type)
GOVERNOR
Every Six M onths or 1 5 ,0 0 0 Miles:
R em ove both g o vern or a ir filt e r s and wash thoroughly
in cleaning solvent that is known to have no detrim en tal
e ffe c t on m etal, nylon, o r rubber m a teria l.
BRAKE VALVE
Every Y ear or 5 0 ,0 0 0 Miles:
D isassem ble brake v a lv e and clean a ll parts. Install
new in let va lv e s and piston seal.
RELAY VALVE
If the re la y v a lv e does not function as d escribed under
S e rv ic e O peration s— R elay V a lve (but in any event once
each y e a r) d isassem b le the va lve and clean a ll rubber
p arts and parts subject to w ea r should be replaced if
worn o r damaged.
Q UICK RELEASE VALVE
Every Y e ar or 5 0 ,0 0 0 Miles:
D isassem b le va lve, clean a ll parts and rep la ce the
diaphragm .
BRAKE CHAMBERS
Every M onth or 2 ,0 0 0 Miles:
Check tr a v e l of brake cham ber push rods and adjust
brakes i f n ecessary. Push rod tr a v e l should be kept at
the minim um without brakes dragging.
E x c e s s iv e tra v e l shortens the s e r v ic e life of brake
cham ber diaphragm s and also resu lts in slow braking
response.
Every Y ear or 5 0 ,0 0 0 Miles:
D isassem b le brake cham bers and clean a ll parts. In­
s ta ll new diaphragms. When rep la cin g re le a s e springs
be su re to use the c o r r e c t spring, otherw ise uneven
braking w ill result.
SLACK ADJUSTERS
The slack adjusters a re fu lly packed with gre a s e when
assem bled and need no p e rio d ic lubrication.
If the slack adjuster is disassem bled fo r any reason it
must be repacked with g rea se in the fo llo w in g way:
1. R em ove one plug fro m the slack adjuster side plate.
2. Using a p ressu re g rea se gun, in ject grea se into the
hole in side c o v e r w hile turning the w orm shaft ap­
p roxim a tely 50 revolutions in one direction.
3. In stall side plate plug secu rely.
4. Rotate worm shaft about 3 revolutions in the opposite
direction .
5. R e fe r to Section 0 - Lubrication fo r additional in­
form ation.
RESERVOIRS
D rain a ir r e s e r v o ir s reg u la rly , as requ ired. L o c a l
conditions govern frequ ency; in dry clim a tes, fo r ex ­
am ple, once a month m ay be sufficient, w hile in humid
areas it may be n ecessa ry to drain r e s e r v o ir s daily.
S atisfactory draining is accom plished only by leavin g
the drain cock open a fter the a ir has escaped and until
a ll drainage stops.
Many an e ffic ie n t r e s e r v o ir arrangem ent has fa ile d in
its norm al function through haphazard maintenance.
D R AIN COCKS
A ll drain cocks should be p e rio d ic a lly checked fo r
leakage, both fo r leakage past the key and leakage through
the body around the key. Leakage of m ore than a one inch
soap bubble in one second is not p erm issib le.
SAFETY VALVE
Every Y ear or 5 0 ,0 0 0 Miles:
The safety v a lv e should be rem oved, disassem bled and
thoroughly cleaned. Adjust to 150 p si b lo w -o ff p ressu re
a fte r reassem b ly.
SINGLE CHECK VALVE
Every Y ear or 5 0 ,0 0 0 Miles:
The check v a lv e should be dism antled and thoroughly
cleaned.
LO W PRESSURE INDICATO R
Every M onth or 1 0 ,0 0 0 Miles:
Check the e le c tr ic a l connections and the a ir p ressu re
at which the contacts c lo se. This should be 58 to 65 psi.
If above o r below this range, rep lace switch.
AIR GAUGE
Check the accu racy of the a ir gauge sem i-annually.
The sim p lest way to do this is to com pare it with another
gauge known to be accurate.
Dash gauges m ay lo s e th eir accuracy a fte r long p eriod s
of s e r v ic e and may re q u ire replacing. Continued use of
dash gauges showing e r r o r o f m ore than 5 p si high o r
low is not recom m ended.
Many state m otor v e h icle
CHEVROLET TRUCK SERVICE MANUAL