Chevrolet 10 Series 1970, Service Manual

Page: 439 / 671

CLUTCHES AND TRANSMISSIONS 7-9
2. Check rubber cup fo r damage o r sw ellin g due to im ­
p ro p er brake fluid. R eplace cup i f n ecessary.
3. Check fit of the piston in the cylin d er bore, using a
fe e le r gauge. This clearan ce should be fro m .002"
to .004".
Assembly
1. In stall seals (new, p re fe ra b ly ) on piston with lip edge
of sea ls to so lid end of piston.
2. L u b ricate piston and sea l assem bly with brake fluid
then in sta ll in cylin d er as shown in F igu re 10.
3. In stall snap rin g (piston re ta in e r) as shown in F ig ­
ure 12.
4. In stall boot o v e r push rod (fig . 13) and in stall push
rod and boot to slave cylin der.
Installation
1. B olt sla ve cylin d er assem bly to engine clutch housing
(fig . 3).
2. Adjust slave cylin der push rod clearan ce, as outlined
in this section, under "C lu tc h P ed a l T ota l T r a v e l/ '
3. Attach hydraulic line to slave cylin der and b leed a ir
fro m system at slave cylin d er bleed fittin g.
CLUTCH CROSS-SHAFT (Figs. 2 and 13)
Removal
1. Disconnect clutch fo rk return spring at fork .
2. Disconnect pedal push rod at cro s s -s h a ft le v e r and
allow clutch fo rk push rod to hang fr e e fro m lo w e r
le v e r.
3. Loosen b all stud nut and slid e stud out of bracket
slot, then lift c ro s s -s h a ft o ff engine b all stud and out
of veh icle.
4. R em ove clutch fo rk push rod fro m c ro s s -s h a ft le v e r
if necessary.
5. R e v e rs e rem ova l procedu re to in stall.
CLUTCHES
DIAPHRAGM SPRIN G CLUTCH
INDEX
Page Page
Maintenance and A d ju s tm e n ts ............................................................ ........ 7-9 Service O p e ra tio n s ................................................................................ ...... 7-10
Preliminary I n s p e c t io n ..................................................................... ........ 7-9 Clutch A ssem bly .................................................................................... 7-10
Clutch Retracting Spring R e p la c e m e n t.......................................... ........ 7-9 Rem oval from V e h ic le ......................................................................... 7-10
Diaphragm Clutch A d ju s t m e n t ....................................................... ........ 7-9 Installation to V e h i c l e ......................................................................... 7-10
MAINTENANCE AND ADJUSTMENTS
PRELIMINARY INSPECTION
T h ere are many things which a ffect good clutch opera­
tion. T h e re fo re , it is n ecessary, b e fo re p e rfo rm in g any
m a jo r clutch operations, to make a p re lim in a ry in spec­
tion to determ in e whether o r not the trouble is actually in
the clutch.
1. Check the clutch pedal and make sure that the pedal
has at least 1/8" fr e e tr a v e l (H ydraulic Clutch Con­
tr o ls ), o r 3 / 4 " - l" (M echanical Linkage).
2. Check the clutch pedal bushing fo r w ear and fo r
sticking on the shaft o r loose mountings.
3. Lu bricate the pedal linkage.
4. Tighten a ll fron t and r e a r engine mounting bolts.
Should the mountings be o il soaked, it w ill be n eces­
sa ry to rep lace them.
CLUTCH RETRACTING SPRING REPLACEMENT
A rattle in the clutch assem bly at idlin g speeds with the
clutch re le a s e d or fa ilu re of the clutch to re le a s e prop­
e r ly may be caused by in su fficien t tension on the p r e s ­
sure plate retra ctin g springs. Th ese troubles can ea s ily
be checked by replacin g the springs, as follow s:
1. R em ove the clutch housing underpan.
2. Hand crank the engine until one retra ctin g spring at­
taching bolt is at the bottom . R em ove the bolt and
retra ctin g spring and in sta ll a new spring.
3. Replace the other retra c tin g springs in the sam e
manner.
4. R eplace clutch housing underpan.
D IA PH R A G M CLUTCH ADJUSTMENT
If clutch fa ils to relea se:
1. Check pedal fo r p ro p er tra v e l and linkage fo r lo o s e ­
ness, adjustments, etc.
F ig . 15—C h e c k in g Pressure P late L ift W /D ia l In d ic a to r
CHEVROLET TRUCK SERVICE MANUAL