ENGINE-ELECTRICAL 6Y-34
SPECIAL TOOLS
J-7607
IGNITION SWITCH
NUT REMOVER
J-9717-2
SUPPORT
TOOL
J-9717-1
PRESS
TOOL
J-9600-2
SHOULDERED
INSTALLER
J-21501
PULLY
ADAPTER
J-5184
CHECKING
SCALE
J-21600
HARNESS ADAPTER
Fig. 4s-Specia! Tools
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 7
CLUTCH AND TRANSMISSIONS
CONTENTS OF THIS SECTION
Clutch
Three-Speed . . .
Overdrive
Three-Speed, (Warner T-16)
Four-Speed (Muncie) . . . .
Page
7-1
7-6
7-9
7-14
7-16
CLUTCH
Page
Four-Speed (Saginaw) 7-20
Powerglide 7-23
Turbo Hydra-Matic 7-36
Special Tools 7-43
INDEX
General Description
Maintenance and Adjustments
Linkage Inspection
Clutch Linkage Adjustment
Component Parts Replacement
Clutch Assembly ......
Removal from Vehicle .
Page
7-1
7-1
7-1
7-2
7-3
7-3
7-3
Installation in Vehicle
Clutch Pedal ..'....,
Clutch Cross Shaft . . .
Removal.......
Repairs
Installation .....
Page
7-4
7-4
7-4
7-4
7-4
7-4
GENERAL DESCRIPTION
A diaphragm spring-type clutch assembly is used with
manual transmissions.
The clutch assembly is enclosed in a 360° bell housing
which must be removed to gain access to the clutch.
V-8 engines (equipped with a 4 speed transmission)
use a bent-finger, centrifugal diaphragm type clutch as-
sembly. All its integral release fingers are bent back to
gain a centrifugal boost and to insure quick re engagement
at high engine speeds.
This type of clutch has the advantages of increasing
pressure plate load as the driven plate wears, and of low
pedal effort with high plate loads without requiring over-
center booster springs on the clutch linkage.
The pressure plate is a high tensile strength iron de-
signed for maximum speed conditions.
The clutch release bearing (fig. 4), used with the bent
finger diaphragm clutch, has an overall length of approxi-
mately
1-1/4".
The longer bearing, used with the straight
diaphragm, will cause inability to obtain free pedal travel,
especially as the clutch wears, resulting in slippage and
rapid wear.
DO
NOT INTERCHANGE!
The clutch is operated by conventional linkage consist-
ing of two groups, upper linkage and lower linkage.
The return spring pre-loads clutch linkage, removing
looseness due to wear. The clutch free pedal travel,
therefore, will increase with linkage wear and decrease
with driven disc wear, and free travel felt at pedal is
throwout bearing lash.
MAINTENANCE AND ADJUSTMENTS
LINKAGE INSPECTION
There are several things which affect good clutch op-
eration. Therefore, it is necessary, before performing
any major clutch operations, to make preliminary in-
spections to determine whether trouble is actually in the
clutch.
Check the clutch linkage to be sure the clutch releases
fully as follows:
1.
With engine running, hold the clutch pedal approxi-
mately 1/2" from floor mat and move shift lever be-
tween first and reverse several times. If this can be
done smoothly, the clutch is fully releasing. If shift
is not smooth, clutch is not fully releasing and ad-
justment is necessary.
2.
Check clutch pedal bushings for sticking or excessive
wear.
3.
Check fork for proper installation on ball stud. Lack
of lubrication on fork can cause fork to be pulled off
the ball.
4.
Check for bent, cracked or damaged cross shaft
levers or support bracket.
5.
Loose or damaged engine mounts may aUiow the en-
gine to shift its position causing a bind on clutch
linkage at the cross shaft. Check to be sure there is
Fig.
1 - Chevrolet Clutch Pedal Free Travel Adjustment
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-3
•BUMPER
CLUTCH FORK
CLUTCH PEDAL
L-4 AND L-6 MODELS
Fig.
3 - Chevy II Clutch Pedal Free Travel Adjustment
to previous heat. The vehicle should be returned to the
Dealership the next day (at least 12 hours) to give clutch
time to cool to normal temperatures. Any slippage
should then be evaluated as follows:
1.
Drive in high gear at 20-25 MPH.
2.
Depress clutch pedal to the floor and rev engine to
2500-3500 rpm.
3.
Engage clutch quickly (snap foot off pedal) and press
accelerator to full throttle.
Engine speed should drop noticeably then accelerate
with vehicle. If clutch is bad, the engine speed will in-
crease.
NOTE: Do not repeat more than once or clutch
, will overheat.
-NUTC NUTC
SPACER F
SPACER F
RODB
' CLUTCH^ SWIVEL B
FORK
ADJUSTING
ROD
A '
V8 ENGINE
ADJUSTING
ROD
A
L6 ENGINE
Fig.
4 - Clutch Pedal Free Travel Adjustment
COMPONENT PARTS REPLACEMENT
CLUTCH ASSEMBLY
Removal From Vehicle
1.
Support engine and remove transmission as outlined
in transmission section.
2.
Disconnect clutch fork push rod and spring.
3.
Remove flywheel housing.
4.
Slide clutch fork from ball stud and remove fork from
dust boot.
NOTE: Ball stud is threaded into clutch hous-
ing and is easily replaced, if necessary.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-4
5.
Install Tool J-5824 to support the clutch assembly
during removal.
NOTE: Look for "X" mark on flywheel and on
clutch cover. If MX" mark is not evident, prick
punch marks on flywheel and clutch cover for
indexing purposes during installation.
6. Loosen the clutch-to-flywheel attaching bolts evenly
1 turn at a time until spring pressure is released,
then remove the bolts, and remove clutch assembly.
Installation to Vehicle
Clean pressure plate and flywheel face. (They should
be free of oil, grease, metal deposits or burned spots).
1.
Position the clutch disc and pressure plate in relar
tive installed position and support them with align-
ment Tool J-5824.
NOTE: The driven disc on the 4 and 6 cylinder
engines is installed with the damfper springs to
the flywheel side; the V-8 is opposite, however,
THE GREASE SLINGER IS ALWAYS ON THE
TRANSMISSION SIDE.
2.
Turn clutch assembly until "X" mark on cover lines
up with "X" mark oh flywheel, then align cover bolt
holes to nearest flywheel holes.
3.
Install a bolt in every hole and tighten down evenly
and gradually until tight (to avoid possible clutch
distortion).
NOTE: Cover loads are as high as 1-1/4 tons.
4.
Remove pilot tool.
5.
Unhook clutch fork and lubricate ball socket and fork
fingers at release bearing end with a high melting
point grease such as graphite and reinstall fork on
ball stud. On Corvette models use Moly Grease.
6. Lubricate the recess on the inside of throwout bear-
ing collar and the throwout fork groove with a light
coat of graphite grease (fig. 4). On Corvette models
use Moly Grease.
7.
Install clutch fork and dust boot into clutch housing
and install throwout bearing to the throwout fork, then
install flywheel housing.
8. Install transmission as outlined in transmission
section.
9. Connect fork push rod and spring.
10.
Adjust shift linkage as outlined in transmission
section.
11.
Perform linkage adjustment for pedal free play and
check clutch release position.
CLUTCH PEDAL
The clutch pedal is the pendant-type hung from a sup-
Fig. 5 - Release Bearing Lubrication and Comparison
port brace common to the brake pedal and must be re-
moved to remove brake pedal. Refer to Section 5 for
brake and clutch pedal service procedure.
CLUTCH CROSS SHAFT (Figs. 6, 7 & 8)
Removal
1.
Remove linkage return and lower linkage springs and
disconnect clutch pedal and fork push rods from re-
spective cross shaft levers.
2.
Loosen outboard ball stud nut and slide stud out of
bracket slot.
3.
Move cross shaft outboard, and as required to clear
inboard ball stud, then merely lift out to remove
from vehicle.
Repairs
The cross shaft has nylon ball stud seats which should
be inspected for wear or damage. Also check condition
of engine bracket ball stud assembly and special anti-
rattle "O" ring. Figures 6, .7
&
8 show component parts
of cross shaft. Replace parts as necessary based on wear
or damage. Lubricate ball studs and seats with graphite
grease before reassembly.
Installation
1.
Reverse removal procedure to install.
2.
Adjust clutch linkage as previously outlined.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-6
L6 ENGINE
V8 ENGINE
Fig.
7 - Lower Linkage Details - Camaro
Fig.
8 - Corvette Lower Linkage Details
THREE-SPEED (SA6INAW FULLY SYNCHRONIZED)
TRANSMISSION
General Description . .
Maintenance and Adjustments
Shift Linkage Adjustment
Shift Control Lever
&
Bracket Assembly
Speedometer Driven Gear ..........
INDEX
Page Page
7-6 Extension Oil Seal Replacement 7-7
7-7 Transmission Side Cover 7-8
7-7 Component Part Replacement 7-8
7-7 Transmission Replacement (exc. Corvette) . 7-8
7-7 Corvette Transmission Replacement 7-9
GENERAL DESCRIPTION
The Saginaw three speed fully synchronized (all forward
gears) transmission incorporates helical drive gears
throughout.
The main drive gear is supported by a ball bearing at
the front end of the transmission case and is piloted at
its front end in an oil impregnated bushing mounted in the
engine crankshaft. The front end of the mainshaft is
piloted in a row of roller bearings set into the hollow end
of the main drive gear and the rear end is carried by a
ball bearing mounted in the front of the extension housing.
The countergear is carried on a single row of rollers at
both ends while thrust is taken on thrust washers located
between the ends of the gear and the thrust bosses in the
case.
Ah anti-rattle plate assembly at the front of the
countergear provides a constant spring tension between the
counter and clutch gears to reduce torsional vibrations.
The reverse idler gear is carried on a bushing finish
bored in place. It rotates on a short idler shaft with a
steel thrust washer tanged into the case against the rear
face. Forward movement is stopped by a snap ring on
the idler shaft.
Gear shifting is manual through shift control rods to
the rearward shift lever of the side cover assembly for
first and reverse gear; and through a cross shaft assem-
bly (Chevrolet models) attached to the forward side cover
lever for second and third gear. All three forward gears
are fully synchronized. The synchronizer assemblies
consist of a clutch hub, clutch sleeve, two clutch key
springs and three energizer clutch keys and are retained
as an assembly on the main shaft by a snap ring.
The transmission may be used as an aid in deceleration
by downshifting in sequence without double-clutching or
any gear clashing. Reverse is not- synchronized, how-
ever, it is a helical gear to insure quiet operation.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-7
MAINTENANCE AND ADJUSTMENTS
CHEVROLET, CHEVELLE, CHEVY II, CAMARO,
SHIFT LINKAGE ADJUSTMENT
In cases where the gearshift linkage has been discon-
nected, it should be adjusted as follows:
1.
Move both transmission shift levers until transmis-
sion is in neutral. Neutral detents in transmission
cover must both be engaged to make this adjustment
correctly. (To check, start engine with clutch dis-
engaged, and release clutch slowly.)
2.
Move selector lever to neutral position. Align first
and reverse tube lever with the second and third
shifter tube lever on the mast jacket. This may be
done by having an assistant hold the mast .jacket shift
levers aligned in neutral position or use a simple
gauge or pin to align these levers in neutral.
3.
Make necessary adjustment to align shift control
rods and transmission levers in neutral position.
Move selector lever through all positions to check ad-
justment and to insure over-travel in all positions.
FLOOR SHIFT LINKAGE ADJUSTMENT
1.
Set Transmission Levers (K) and (L) in neutral de-
tent position.
2.
Move Transmission Control Lever (A) to neutral de-
tent and insert Locating Pin (D) into notch of Lever
and Bracket Assembly.
3.
Install Nut (N) and Clevis (M) on Rod (J) loosely,
attach Rod to Lever (B) and secure with retainer.
4.
With Lever (B) against Locating Pin, adjust Clevis
at Lever (L) until Clevis pin passes freely through
holes and secure with washer and cotter pin. Tighten
Nut (N).
5.
Install Nuts (E) and (G) and Swivel (F) loosely on Rod
(H),
attach Rod to Lever (K) and secure with retainer.
6. With Lever (C) against Locating Pin, attach Swivel to
lever and secure with retainer. iRun Nut (G) against
Swivel, then tighten Nut (E) against Swivel.
7.
Remove Locating Pin and check shifts to insure
proper operation. Readjust clevis and swivel if nec-
essary.
LEVER (A)
LEVER (L) CLEVIS (M)-NUT (N
LEVER (C)
ROD(J).
" - -
LEVER (K) ROD (H)^ NUT '(G) SWIVEL (F) ^NUT (E)
SHIFT CONTROL LEVER AND BRACKET ASSEMBLY
If disassembly of this control lever and bracket assem-
bly is necessary refer to Figure 2A for parts breakdown
and relative positioning for assembly.
SPEEDOMETER DRIVEN GEAR
Disconnect speedometer cable, remove lock plate to ex-
tension bolt and lock washer and remove lock plate. In-
sert screwdriver in lock plate slot in fitting and pry fitting
gear and shaft from extension. Pry "O" ring from groove
in fitting.
Install new "OM ring in groove in fitting. Coat "O" ring
and driven gear shaft with transmission lubricant and in-
sert shaft.
Hold the assembly so slot in fitting is toward lock plate
boss on extension and install in extension. Push fitting
into extension until lock plate can be inserted in groove
and attach to extension.
EXTENSION OIL SEAL REPLACEMENT
.1.
Remove propeller shaft as outlined in Section 4 and
disconnect any necessary items to obtain clearance.
2.
Pry seal out of extension.
3.
Wash counterbore with cleaning solvent and inspect
for damage.
4.
Prelubricate between sealing lips and coat new seal
O.D. with Permatex or equivalent and start straight
in bore in case extension. Using Tool J-5154, tap
seal into counterbore until flange bottoms against
extension.
Fig.
1A- Shift Linkage Adjustment (Typical)
Fig.
2A - Corvette 3 Speed Control Lever and Bracket Assembly
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-3
DETENT CAM
DETENT SPRING
DETENT CAM
2-3 SHIFT
FORK
DETENT CAM
PIVOT PIN
1ST & REV. 1ST& REV.
SHIFTER SHAFT SHIFT FORK
DETENT CAM
RETAINER RING
2-3 SHIFTER SHAFT
Fig. 3A
•*
Transmission Side Cover, Shift Fork and Detent Assembly
5. Reinstall propeller shaft and any items removed to
obtain clearance.
TRANSMISSION SIDE COVER
Removal •
1.
Disconnect control rods from levers; remove 2-3
cross shaft (Chevrolet)
2.
Shift transmission into neutral detent positions before
removing cover.
3.
Remove cover assembly from transmission case
carefully and allow oil to drain.
Disassembly (Fig. 3A)
1.
Remove the outer shifter levers.
2.
Remove both shift forks from shifter shaft assem-
blies.
Remove both shifter shaft assemblies from
cover. "OM ring seals around shifter shaft may now
be pryed out if replacement is required because of
damage.
3.
Remove detent cam spring and pivot retainer "C"
ring. Remove both detent cams.
4.
Replace damaged parts.
Assembly (Fig. 3A)
1.
With,
detent spring tang projecting up over the
2nd
and
3rd shifter shaft cover opening install the first and
reverse detent cam onto the detent cam pivot pin.
With the detent spring tang projecting up over the
first and reverse shifter shaft cover hole install the
2nd an£ 3rd detent cam.
2.
Install detent cam retaining "C" ring to pivot shaft,
and hook spring into detent cam notches.
3.
Install both shifter shaft assemblies in cover being
careful not to damage seals. Install both shift forks
to shifter shaft assemblies^ lifting up on detent cam
to allow forks to fully seat into position.
4.
Install outer shifter levers, flat washers, lock wash-
ers and bolts.
Installation
1.
Shift shifter levers into neutral detent (center) posi-
tion.
Position cover gasket on case.
2.
Carefully position side cover into place making sure'
the shift forks are aligned with their respective
mainshaft clutch sliding sleeves.
3.
Install cover attaching bolts and tighten evenly to
specified torque.
4.
Remove filler plug and add lubricant specified in
Section 0, to level of filler plug hole.
COMPONENT PART REPLACEMENT
TRANSMISSION REPLACEMENT (EXC. CORVETTE)
Removal From Vehicle
1.
Remove propeller shaft assembly.
2.
Disconnect speedometer cable at transmission.
3.
Disconnect shifter rods at transmission levers.
4.
Support engine assembly.
5. Remove transmission to clutch housing bolts.
6. Remove transmission crossmember to mount bolts.
7. Loosen transmission crossmember and move rear-
ward or remove.
8. Slide transmission rearward and remove.
Installation in Vehicle
1.
Raise transmission into position and slide forward
piloting clutch gear retainer into clutch housing.
2.
Install transmission to clutch housing retaining bolts
and lock washers, torque to 50 ft. lbs.
3.
Repositioning transmission crossmember and install
retaining bolts.
4.
Install transmission crossmember to mount bolts.
5. Connect and adjust shift rods at transmission levers
and cordon shaft to 2nd and 3rd lever on Chevrolet
Models. (Fig. 4A)
Fig. 4A - Chevrolet 2-3 Shift Lever Cordon Shaft
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-9
6. Connect speedometer cable.
7. Install propeller shaft assembly.
8. Fill transmission with lubricant specified in Section
O.
CORVETTE TRANSMISSION REPLACEMENT
, 1. Disconnect battery ground cable.
2.
Pisassemble transmission shift control lever by un-
screwing ball from lever, lifting out
"T"
handle re-
turn spring and "T" handle, then remove the anti-
rattle bushings.
3.
Raise front and rear of vehicle.
4.
Insert a block of wood between the top of the dif-
ferential carrier housing and the underbody (to pre-
vent upward travel of the carrier when the carrier
front support is disconnected).
5. Disconnect the differential carrier front supportfrom
its frame bracket, by removing the nut on the under-
side of the biscuit mount.
6. Pry the carrier downward to relieve load while re-
moving the two center mounting bolts from the car-
rier front support. (To pry carrier downward insert
crowfoot end of a pry bar through the opening in the
carrier front support, hooking end of bar over top of
the center mounting bolt pad cast in the underside of
the carrier.)
7. Pivot carrier support downward for access to prop
shaft "U" joint.
8.
.
Disconnect prop shaft front and then rear "U" bolts.
9. Disconnect parking brake cable from ball socket at
idler lever located near center of underbody.
10.
Remove prop shaft by moving shaft forward.
11.
Remove heat deflectors from the right and left ex-
haust pipe.
12.
Remove left bank exhaust pipe.
13.
Remove right bank exhaust pipe and heat riser.
14.
Disassemble the transmission mount, as follows:
a. Remove the two bolts that attach rear mount
cushion to the rear mount bracket.
b.
Support engine under oil pan and raise engine to
remove load from rear mount cushion.
CAUTION: To avoid damage to oil pan, a suit-
able wide base, heavy wood platform should be
placed between the jack pad and the oil pan.
c. Remove the three transmission mount bracket-
to-
crossm ember bolts and remove mount bracket.
d. Remove the two bolts from mount pad to trans-
mission case and remove rubber mount cushion
and exhaust pipe "yoke".
15.
Disconnect transmission linkage by removing the
shift levers at the transmission side cover.
16.
Disconnect speedo cable at transmission extension.
17.
Remove transmission output shaft slip yoke.
NOTE:
The yoke is removed to avoid tearing
the heat reflecting pad on the underbody, when
the transmission is being removed.
18.
Remove two bolts to disconnect the transmission
gearshift control lever and bracket assembly from
its adapter plate on side of transmission. Lower
transmission assembly from the vehicle, letting the
gearshift lever slide down and through the dust boot
in the console.
19.
Remove transmission-to-clutch housing attaching
bolts.
20.
Slide transmission assembly rearward from clutch
and rotate transmission for access to the three flat
head machine screws in the control lever bracket
adapter plate. Remove adapter plate. Rotate trans-
mission back to the upright position.
21.
To allow room for transmission removal slowly
lower the rear of engine until the tachometer drive
cable at the distributor just clears the horizontal
ledge across the front of dash.
CAUTION: The tachometer cable can be easily
damaged by heavy contact with the dash. Slide
transmission rearward out of the clutch, then
tip front end of transmission downward and
lower the assembly from vehicle.
22.
Reinstall transmission assembly by performing above
steps in reverse order.
TRANSMISSION OVERDRIVE
INDEX
Page
General
Description 7-10
Maintenance
and Adjustments 7—10
Governor
Switch and Pinion .............. 7-10
Sun
Gear Solenoid Oil Seal and Control
Cable
Bracket 7-10
Case
Rear Oil Seal 7-10
Removal
7-10
Installation
. . . . . 7-10
Control
Shaft Lever and Oil Seal 7-10
Speedometer
Driven Gear 7-10
Electrical
Unit Checks 7-11
Overdrive
Relay . 7-11
Page
Air
Gap 7-11
Point
Opening 7-11
Closing
Voltage 7-11
Solenoid
. 7-11
Closing
Coil 7-11
Engaging
Spring . - 7-11
Ignition
Grounding Contact . 7-11
Governor
Switch 7-11
Kickdown
Switch 7-11
Diagnosis
- Overdrive 7-12
Mechanical
. 7-12
Electrical
7-13
CHEVROLET CHASSIS SERVICE MANUAL