Chevrolet CAMARO 1979 Service Manual page 419

B R A K E S 5 . 1 7
C O M B ' N A T I O N V A L V E
Tosting Eloctrical Circuit of Combination Vâlv€
l. Disconnect wire from switch termirar ano use a
jumper to connect wir€ to a good ground.
2. Turn ignition key on "On" - waming lamp should
light. If lamp does nor light, butb is bumed our or electrical
circuit is defective. Replace bùlb or repair electrical circùit
3. When warning lamp iights, turn ignition swirch of|
Disconnect jumper and reconnect wire to switch terminal.
Testing Warning Light Switch Portion of
Combination Vâlvo
The pressure differential switch hâs a nylon body. The
switch is not servicedi if it fails or is damaged, the
combinâtion valve must be rcplâced.
L Raise vehicie on hoist. Attach a bl€€der hose ro a
rear brake bleed screw and immerse the other end of the
hose in â container partially filled \rith clean brak€ fluid.
Be sure mâster cylinder reservoirs are full.
2. Turn ignitioir switch to "On"; open bleeds screw
while a heiper applies moderat€ pressure to the brake pedal;
wârning lamp should light. Close bl€eder screw before
helper releâses brâke pedal. Reapply brake pedâl with
moderate-to-heâvy pressure; light should go out.
3. Attâch the bleeder hose to a front brake bieeder
screw ând repeat above test. Warning lamp action should
be the same as in Step No. 2. Turû ignition swirch off.
4. If wârning lâmp does not light during Steps 2 and
3 but does light when ajumper is connected to ground, the
wârning light switch portion of the combination valve is
d€fective. Do not attempt to disassemble the combination
vâlve. lfâny portion ofthe combination valve is defective,
it must be replaced with a new combinâtion vâ1ve.
5. Lower vehicle to floor. Check and refill mâster
cylinder to proper level.
Replacement
The combinâtion valve is not repainble and must be
serviced as a complete assembly.
L Disconnect hydraulic lines at combination valve.
Plug lines to prevent loss of fluid and entÉnce of dirt.
Disconnect wâming switch wiring harness ftom valve
2. Remove combination valve.
3. lnstâll combinâtion valve by reversing rcmoval steps.
4. Bleed entirebmke system. Do not move vehicle until
â firm brâke pedai is obtained.
B R A K E P E D A L
R e m o v a l ( F i g . 5 - 1 2 )
R€fer to Section iA for removal of air conditioning
components if necessary.
l. Disconnect bâttery ground câble.
2. Disconnect clutch pedal return spring (manual
transmission vehiclet.
3. Remove clip retainer from push rod pin. This clip
âlso retâins the pùll bâck spdng extension on "F" and "X"
4. Remove nut ftom pedal pivor shafr boir ând slide
shaft bolt out far enough to clear the brake pedal. This shaft
is also the clutch pedal pivot with manuâl rransmission
vehicles.
5. Withdraw brâke pedal, spacer and bushings.
Installâtion
L Lubricate and install the spacer and bushings in the
pedal hub. usins Delco Brake Lube (or equivâtenr).
2. Install brake pedal in support assembly.
3. Slide pivot shaft bolt th.ough pedal hub ând insrall
CAUTION: 56o "Caution' on Page 1 ot
this sgction.
4. Instâtl the return spring extension and push rod and
install clip rerainer. Instâll the reiurn spring.
5. Connect clutch pedâi return spring (manual
transmission vehiclet.
6. Connect battery ground cable.
MASTER CYLINDER
Filling Brake Mast6r Cylind€r
The master cylinde. must be kept properiy filled to
insure adequate reserve and to prevent air from ente.ing the
hydraulic syslem. However, because of expansion due to
heat abso.bed f.om brakes and from engine, mâster cylinder
must not be overlilled.
The brake Ruid r€servoir is on the mâster cylinder
which is located under the hood on the left side ofthe dash.
Thoroughly clean reservoir cover before removal to
avoid getting dirt into reservoir. Remove cover and
diâphragm. Add fluid as required to bi.ng level to 1/4'
(plùs or minus l,/8") frorn the low€st po ion of the top of
eâch reservoir. Use Delco SuFeme No. 1l Hydraulic Bfake
Fluid or equivaient.
NOTICE: The "A" Mod€l master cylinder should be
filled only to the top of the reservoir divider to âvoid
overfloq, when the cover is instâlled.
Do not use shock absorber fluid or any other flùid
which contains mineral oil. Do not use â container which
has been used for minerai oil or a container which is wet
from water. Mineml oil will cause swelling ând distortion
of rubber parts in the hydraulic bmke system ând wâter will
mix with brake fluid, lowering the fluid boiling point. Keep
âll fluid containers capped to prevent wate. contaminâtion.
Removal
1. Disconnect brake pipes from master cylinder ând
tape end of pipes to prevent entmnce ofdirt.
2. Mânual brâkê only- Disconnect brake pedal
from master cylinder push rod,
3, Remove two nuts holding master cylinder to dâsh
or power cylinder and remove master cylinder ftom vehicle.
Be careful not to drip brâke fluid on exterior paint.
Disassembly {Figs. 5-13 thru 5-'18)
Repair procedures for the "A' Model master cylinder
âre the same as previous units exc€pt for the iese oir
s€rvicing procedure.
i. Clean outside of master cylinder thoroughly.
Remove rcservoir cover and diâphragm. Turn cylinder over
ând pump push rod by hând to drain âll brakefluid. Always
discard used fluid.
2. Manual bfaks only-- Pull boot âwây from master