Chevrolet 10 Series 1970, Руководство по обслуживанию

Страница: 431 / 671

SECTION 7
TRUCK CLUTCHES & TRANSMISSIONS
CONTENTS OF THIS SECTION
Page
Page
Clutch C o n t r o ls .................................................................................... 7- 1
Clutches ............................................................................................... 7 - 9
Manual T ra n sm is sio n s......................................................................... ....... 7-13
Alum inum P o w e r g lid e ......................................................................... 7-39
Tu rbo Hydra-Matic 350 ....................................................................... 7-46
Tu rbo Hydra-Matic 400 ....................................................................... 7-54
Special T o o l s ........................................................................................ 7-63
CLUTCH CONTROLS
INDEX
Page Page
General D e s crip tio n .....................................................
Maintenance and A d ju stm e n ts...................................
Clutch Free Pedal Travel Adju stm ent (M echanical)
Insu fficient Clutch R e le a s e ......................................
Clutch Pedal A djustm ent (H y d r a u lic )....................
Clutch Pedal T o ta l T r a v e l ........................................
7-1 Clutch Pedal Free Travel A d ju s tm e n t............................................. 7-5
7-4 Clutch Pedal (E x cep t T ilt C a b ) ........................................................ 7-5
7-4 Clutch Pedal (T ilt C a b ) ..................................................................... 7-5
7-4 Slave Cylinder ................................................................................... 7-6
7-4 Clutch Cross Shaft ............................................................................
7-9
7-5
GENERAL DESCRIPTION
The operating controls fo r trucks are eith er mechan­
ic a l or hydraulic. The m echanical linkage consists of
pendant type pedal, return spring, pedal push rod, c r o s s ­
shaft, fo rk push rod, clutch fo rk and throwout bearing
(fig . 1). The pedal push rod is routed v e rtic a lly , inside
the cab, fro m the pedal le v e r down through a seal boot
on the toe pan, to the cro s s -s h a ft le v e r . When the clutch
pedal is depressed, the pedal pull o r push rod moves
upward rotating the cross-sh a ft, pushing the fo rk push
rod rearw a rd , and pivoting the clutch fo rk to m ove the
throwout bea rin g against the clutch re le a s e fin g e rs and
re le a s in g the clutch.
The Step Van uses m echanical linkage activated by a
flo o r pedal mounted through a p ivot shaft on a fram e
bracket (fig . 2). A pull rod connects the pedal to the
cro s s -s h a ft to activate the clutch as before.
The hydraulic controls consist o f pedal, pedal push rod,
main cylinder, tubing, sla ve cylin der, fo rk push rod,
clutch fo rk and throwout bearing.
When the clutch pedal is depressed, brake fluid is
fo rc e d from the main cylin der into the slave cylin der
(fig . 3) m oving the push rod against the clutch fo rk to r e ­
lease the clutch as b efo re. When the pedal is released ,
the clutch fo rk return spring fo rc e s fluid fro m the slave
cylin der back to the m a ster cylinder.
A fittin g is p rovided on the slave cylinder fo r bleeding
a ir fro m the system as is done with hydraulic brakes.
The fluid le v e l should be maintained approxim ately 1/2"
below the top of m aster cylin der r e s e r v o ir .
On T D -T G 500 and TD 600 M odels the clutch re le a s e
bearing is m oved by a yoke attached to a shaft through the
transm ission half of the clutch housing (fig . 4). The hy­
draulic slave cylin der pushes a le v e r attached at the end
o f the throwout yoke shaft, rotating the shaft and yoke and
m oving the throwout bearing against re le a s e fin g e rs of
clutch assem bly.
On v eh icles equipped with a yoke and shaft type r e le a s e
le v e r , the grease cup (attached by hose to re le a s e b e a r­
ing) is fille d with a graphite type grease and should be
turned one-turn each 1,000 m iles and r e fille d each 6,000
m iles.
CHEVROLET TRUCK SERVICE MANUAL