Chevrolet 10 Series 1970, Руководство по обслуживанию

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LUBRICATION 0-18
A utom atic Brake Adjusters
M ost trucks with hydraulic brakes a re equipped with
self-a d ju stin g brakes which elim in ate p e rio d ic brake
adjustments. TH E S E L F -A D J U S T IN G M ECH ANISM IS
A C T U A T E D , AS NEED ED , W H EN EVER TH E TR U C K IS
M OVED IN REVERSE A N D TH E B RAKES A R E A P P L IE D .
POWER BRAKE V A C U U M UNITS
T ru ck s equipped with p ow er brakes u tilize engine
vacuum to reduce the braking e ffo rt to much le s s than
is requ ired with re g u la r brakes. A b u ilt-in vacuum r e ­
s e rv e w ill supply two o r m ore pow er assisted brake ap­
p lication s a fte r the engine has stopped. A fte r the v a c ­
uum r e s e r v e has been exhausted, the veh icle can be
stopped u tilizin g the manual portion o f the pow er brake
syste although con siderably m ore foot p ressu re w ill be
needed to stop the veh icle.
Vacuum brake a ir clea n er fo r fra m e mounted vacuum
b o o sters should be cleaned sem i-annually.
FULL AIR BRAKES
Compressor
R em ove c o m p resso r a ir stra in er and inspect o r r e ­
p la ce e v e ry 6000 m ile s o r often er. The elem ent can be
cleaned in kerosene o r m in era l s p irits. C lean ers o f the
a rom a tic compound must not be used. The elem ent
should be squeezed (not wrung) dry a fte r cleaning.
Draining A ir Tanks
Condensation must be drained fro m a ll a ir tanks daily.
T o drain tanks p ro p e rly , lea ve drain cocks open until a ll
a ir excapes and draining stops. During extrem e cold
w eather operation, it may be n ecessary to use an alcohol
eva p o ra to r to preven t m oisture from fre e z in g in a ir
tanks.
NOTE: D aily draining is not n ecessary i f truck
is equipped with the optional m oisture e je c to r
v a lve.
Q uick Release V a lv e
E v e ry Y e a r o r 50,000 M ile s : D isassem b ly va lve, clean
a ll p arts and rep lace the diaphragm .
Brake Cham bers
E v e ry Month o r 2,000 M ile s : Check tra v e l o f brake
cham ber push rods and adjust brakes if n ecessary.
E v e ry Y e a r o r 50,000 M iles: D isassem b le brake
cham bers and clean a ll p arts. Install new diaphragm s.
Drain Cocks
A ll drain cocks should be p e rio d ic a lly checked fo r
leakage.
Safety V a lv e
E v e ry Y e a r o r 50,000 M iles: The safety va lve should
be rem oved, disassem bled and thoroughly cleaned.
Single Check V a lv e
E v e ry Y e a r o r 50,000 M iles: The check va lve should
be dism antled and thoroughly cleaned.
Low Pressure Indicator
E v e ry Month o r 10,000 M iles: Check the e le c tric a l
connections and the a ir p ressu re at which the contacts
clo s e .
Brake V a lv e (Standard Brake System)
E v e ry Y e a r o r 50,000 M iles: D isassem b le brake valve
and clean all p arts. Install new inlet v a lv e s and piston
seals.
Brake Control V a lv e (D u al Brake System)
E very 200 operating hours o r a fte r 5,000 m ile s o r once
each month, lubricate pedal m echanism . A ls o check the
le v e r ’ s linkage fo r adjustment and/or binding.
E v e ry 3,600 operating hours o r a fte r each 100,000
m ile s , clean and replace parts as requ ired.
E v e ry 7,200 operating hours o r a fte r 200,000 m iles, or
e v e r y two y e a rs , disassem ble brake va lve, clean and in­
spect all p arts. Install new p arts w here they a re found
to be worn o r damaged.
Emergency V a lv e
E v e ry y e a r o r a fte r 50,000 m iles, the Em ergency
V a lve should be disassem bled, cleaned and lubricated.
Rubber parts should be replaced and any other parts
showing signs o f w e a r o r damage should also be
rep laced .
Double Check Valves
Once a y e a r o r e v e ry 50,000 m iles, the check va lve
should be rem oved, dismounted, and cleaned.
Tractor Protection V a lv e
Thoroughly check and if n ecessary clean, replace
p arts and lu bricate.
Double Check V a lv e and Stop Lamp Switch
E v e ry month o r a fte r 10,000 m ile s , check the e le c t r i­
cal connections and the operation.
E very y e a r o r a fter 50,000 m iles, the combined stop
ligh t sw itch and double check va lve should be d isa ssem ­
bled and cleaned and parts rep laced as requ ired.
Relay V a lv e
Once a y e a r check va lve, clean o r rep lace parts.
Front Brake Limiting V a lv e
Front brake lim itin g va lve is used on som e veh icles
to p rovid e a means o f reducing the a ir p ressu re applied
to the front b rakes when operating on slip p ery road.
Putting the le v e r in ' 'S L IP P E R Y RO AD ” position r e ­
duces p ressu re on front brakes to half o f that on re a r
brakes so that front w heels have le s s tendency to slide
and steerin g control is maintained. K eep le v e r in “ D R Y
R O AD ” position under a ll norm al operating conditions.
WHEELS A N D TIRES
WHEEL NUT T O R Q U E S -
1 0 -3 0 Series
On a new veh icle o r a fte r the wheel has been changed,
the wheel nut torque must be checked at 100, 1,000 and
6,000 m ile s and e v e ry 6,000 m ile s th erea fter.
CHEVROLET TRUCK SERVICE MANUAL