ENGINE-ELECTRICAL 6Y-33
O
V-8 ENGINE
STARTING MOTOR
Fig.
2s—V-8 Starting Circuit Diagram
2.
3.
From battery negative post
To
starting motor
housing.
From solenoid battery terminal
To
solenoid motor
terminal.
If voltage drop
in
any
of
above check exceeds 0.2 volts,
excessive resistance
is
indicated in that portion
of
start-
ing circuit
and the
cause
of the
excessive resistance
should
be
located
and
corrected
in
order to obtain maxi-
mum efficiency in the circuit.
CAUTION:
Do not
operate
the
starting motor
continuously
for
more than
30
seconds
to
avoid
overheating.
When
the
solenoid fails
to
pull
in, the
trouble may be
due
to
excessive voltage drop in the solenoid control cir-
cuit.
To
check
for
this condition, close
the
starting
switch
and
measure
the
voltage drop between
the
BAT-
TERY terminal of the solenoid and the
SWITCH (S)
termi-
nal
of
the solenoid.
1.
If
this voltage drop exceeds 3.5 volts, excessive
re-
sistance
in the
solenoid control circuit
is
indicated
and should be corrected.
2.
If the
voltage drop does not exceed 3.5 volts and the
solenoid does not pull in, measure the voltage availa-
ble
at
the SWITCH terminal
of
the solenoid.
3.
If the
solenoid does
not
feel warm,
it
should pull
in
whenever the voltage available
at
the SWITCH termi-
nal
is 7.7
volts
or
more. When
the
solenoid feels
warm,
it
will require
a
somewhat higher voltage
to
pull in.
STARTING MOTOR AND SOLENOID CHECK
The following checks
may be
made
if the
specific
gravity of the battery
is
1.215
or
higher.
1.
If the
solenoid does
not
pull in, measure the voltage
between
the
switch
(S)
terminal
of the
solenoid
and
ground with the starting switch closed.
CAUTION:
If the
solenoid feels warm, allow
to
cool before checking.
If
the
voltage
is
less than 7.7 volts, check for ex-
cessive resistance
in the
solenoid control circuit.
If
the
voltage exceeds 7.7 volts, remove the starting
motor
and
check
(1)
solenoid current draw,
(2)
starting motor pinion clearance,
and (3)
freedom of
shift lever linkage.
2.
If
the solenoid "chatters" but does not hold in, check
the solenoid
for an
open "hold-in" 'winding. When-
ever
it is
necessary
to
replace
a
starting motor
solenoid, always check starting motor pinion
clearance.
3.
If
motor engages
but
does
not
crank
or
cranks
slowly, check
for
excessive resistance
in the ex-
ternal starting circuit, trouble within
the
starting
motor,
or
excessive engine resistance
to
cranking.
SERVICE OPERATIONS
STARTING MOTOR
REMOVAL AND INSTALLATION (Fig.
3s)
The following procedure
is a
general guide
for all
vehicles
and
will vary slightly depending
on
series
and
model.
1.
Disconnect battery ground cable at battery.
2.
Raise vehicle
to a
good working height.
3.
Disconnect all wires
at
solenoid terminals.
NOTE: Reinstall
the
nuts
as
each wire
is
dis-
connected
as
thread size
is
different but may be
mixed and stripped.
4.
Loosen starter front bracket (nut on V-8 and bolt on
L-6) then remove two mount bolts.
5.
Remove
the
front bracket bolt
or nut and
rotate
bracket clear
of
work area then lower starter from
vehicle
by
lowering front end first
—
(hold starter
against bell housing
and
sort
of
roll end-over-end).
6. Reverse
the
removal procedure
to
install. Torque
the mount bolts
to
25-35
ft.
lbs. first, then torque
brace bolt.
7.
Check operation
of
starter on vehicle.
Fig.
3s—Starter Mounting
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 7-24
is at the full mark on the dip stick, it is just slightly be-
low the planetary gear unit. If additional oil is added,
bringing the oil level above the full mark, the planetary
unit will run in the oil, foaming and aerating the oil. This
aerated oil carried through the various oil pressure pas-
sages (low servo, reverse servo, clutch apply, converter,
etc.) may cause malfunction of the transmission assem-
bly, resulting in cavitation noise in the converter and
improper band or clutch application. Overheating may
also occur.
If the transmission is found consistently low on oil, a
thorough inspection should be made to find and correct
all external oil leaks.
PERIODIC OIL CHANGE
The transmission oil should be changed periodically as
recommended in Section 0, and whenever transmission is
to be removed from the vehicle for repairs.
1.
Run engine for one minute in neutral prior to chang-
ing.
2.
Be sure vehicle is level or raise from the rear only.
3.
Remove the oil pan drain plug and allow oil to drain
thoroughly into a pan or can.
Replace drain plug and refill with approximately two
quarts of oil specified in Section 0.
NOTE: To refill the transmission, remove dip
stick from oil filler tube and refill transmission
with oil specified in Section 0 using filler tube
and funnel J-4264. Then, after shifting into all
ranges at idle speed to fill all oil passages, the
engine should be run at 800-1000 rpm with the
transmission in Neutral until the oil warms up,
then add oil as required to raise the fluid level
to the full mark on the dip stick. Refill capacity
is approximately 2 qts.
4.
Fig.
1PG - Adjusting Low Band Using J-21848
PERIODIC LOW BAND ADJUSTMENT (Fig. 1PG)
Low band adjustment should be periodically performed
at 12,000 mile intervals, or sooner, as necessary if op-
erating performance indicates low band slippage.
1.
Raise vehicle and place selector lever in neutral.
2.
Remove protective cap from transmission adjusting
screw.
3.
a. On Corvette Models: Drop left exhaust pipe for
clearance.
b.
On Chevelle Models: To gain clearance between
underbody and transmission, it may be necessary
to remove rear mount bolts from crossmember,
and move transmission slightly toward passenger
side of vehicle. .
4.
Loosen adjusting screw lock nut 1/4 turn and hold in
this position with wrench.
5.
Using Special Tool J-21848 adjust band to 70 in. lbs.
and back off four (4) complete turns for a band which
has been in operation for 6,000 miles or more,.or
three (3) turns for one in use less than 6,000 miles.
CAUTION: Be sure to hold the adjusting screw
lock nut at 1/4 turn loose with a wrench during"
the.adjusting procedure.
6. Tighten the adjusting screw lock nut to specified
torque.
CAUTION: The amount of back-off is not an
approximate figure, it must be exact.
MANUAL SHIFT LINKAGE CHECK & ADJUST
(Column Type)
1.
The shift tube and lever assembly must be free in the
mast jacket. See Section 9 for alignment of steering
column assembly if necessary.
2.
To check for proper shift linkage adjustment, lift
the transmission selector lever towards the steering
wheel. Allow the selector lever to be positioned in
drive (D) by the transmission detent.
NOTE: Do not use the indicator pointer as a
reference to position the selected lever. When
performing linkage adjustment, pointer is ad-
justed last.
3.
Release the selector lever. The lever should be in-
hibited from engaging low range unless the lever is
lifted.
4.
Lift the selector lever towards the steering wheel,
and allow the lever to be positioned in neutral (N) by
the transmission detent.
5.
Release the selector lever. The lever should now
be inhibited from engaging reverse range unless the
lever is lifted.
6. A properly adjusted linkage will prevent the selector
lever from moving beyond both the neutral detent, and
the drive detent unless the lever is lifted to pass
over the mechanical stop in the steering column.
7.
In the event that an adjustment is required, place
the selector lever in drive (D) position as determined
by the transmission detent. See Steps 2 and 3.
8. Loosen the adjustment swivel at the cross-shaft,
and rotate the transmission lever so that it contacts
the drive stop in the steering column.
9. Tighten the swivel and recheck the adjustment. See
2 and 6.
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY AND CHASSIS 12-29
Fig.
43b - Speed Warning Device
TEMPERATURE AND/OR OIL PRESSURE
GAUGE
1.
Disconnect battery ground cable.
2.
Remove ash tray and ash tray retainer.
3.
Disconnect A/C hose from the distributor duct.
4.
Disconnect wiring connectors and lamp bulbs from
rear of gauge.
5. Disconnect oil pressure pipe fitting from rear of oil
pressure gauge.
6. Remove (3) screws retaining gauge assembly to
cluster cover and disengage unit from cover.
7. Remove (4) retaining nuts and remove gauge from
template.
8. To install, reverse removal procedure.
INDICATOR LIGHT REPLACEMENT
To replace any indicator or cluster bulb, unsnap the
proper socket from rear of instrument cluster, remove
and replace bulb, and reinsert unit into rear of cluster
housing.
OIL PRESSURE INDICATOR
If the light does not come on when the ignition switch is
turned on, or if the light comes on and remains on after
the engine is started, one or more the following condi-
tions is indicated:
• Low oil pressure
• Defective wiring or switch
• High engine temperature
Switch Replacement
1.
Disconnect wiring harness connector from sender
unit terminal (located in block above starter on L-6
engines and at left front of distributor on V-8
engines).
2.
Remove sender unit using Tool J-21757, replace with
new unit, and check operation.
GENERATOR INDICATOR
Ignition on, Engine not Running and
Telltale Light Off
1.
Indicator bulb burned out, replace bulb.
2.
Open circuit or loose connection in the telltale light
circuit.
Telltale Light Stays on after Engine is Started
If indicator light does not go out at engine idle speed,
refer to' Charging Systems under Engine Electrical,
Section 6Y.
TEMPERATURE
(COOLING
SYSTEM)
INDICATOR
The temperature indicator circuit, consists of two re-
motely located units, indicator gauge and engine sender
unit. The indicator gauge on all models uses a single
red light to indicate an overheated engine condition.
Engine Sender Unit Replacement
1.
Drain engine cooling system to a level below unit.
2.
Remove sender unit (located in the inlet manifold
near water pump housing on V-8 engines and in the
cylinder head near an exhaust port on L-6 engines)
and replace with new unit.
3.
Refill cooling system and check operation of unit.
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY AND CHASSIS 12-34
5. To replace, reverse the removal procedure.
SPEEDOMETER REPLACEMENT
1.
Remove instrument cluster as previously described
in this section.
2.
Remove clock set shaft knob.
3.
Remove eight screws securing cluster housing to
bezel trim panel. Separate parts carefully observing
stack up of parts.
4.
Remove two screws securing speedometer head to
rear of cluster housing.
NOTE:
Servicing of the speedometer head
should be performed by an authorized AC Speed-
ometer Service Station.
5. To install, reverse the removal procedure..
SPEEDOMETER CABLE
Replacement or Lubricatibn
1.
Disconnect the speedometer cable from the speed-
ometer head. Remove the old cable by pulling it out
from speedometer end of conduit.
NOTE:
If old cable is broken it may be neces-
sary to remove lower piece from transmission
end of conduit.
2.
Lubricate the lower 3/4 of cable with speedometer
cable lubricant and push the cable into the conduit.
Connect the upper end to the speedometer head and
road test vehicle for proper speedometer operation.
INDICATOR LIGHT REPLACEMENT
To replace any indicator or cluster bulb, unsnap the
proper socket from rear of instrument cluster, remove
and replace bulb, and reinsert unit into rear of cluster
housing.
OIL PRESSURE INDICATOR
If the light does not come on when the ignition switch
is turned on, or if the light comes on and remains on
after the engine is started, one or more of the following
conditions is indicated:
• Low oil pressure
• High engine temperature
• Defective wiring or switch
Switch Replacement
1.
Disconnect wiring harness connector from sender
unit terminal (located in block above starter on
L-6 engines and at left front of distributor on V-8
engines).
2.
Remove sender unit, replace with new unit, and
; check operation.
GENERATOR INDICATOR
1.
Ignition on, engine not running and telltale light off.
a. Indicator bulb burned out, replace bulb.
b.
Open circuit or loose connection in the telltale
light circuit.
2.
Telltale light stays on after engine is started.
a. If indicator light does not go out at engine idle
speed, refer to Charging Systems under Engine
Electrical, Section 6Y.
TEMPERATURE (COOLING SYSTEM) INDICATOR
The temperature indicator circuit consists of two re-
motely located units, indicator gauge and engine sender
unit. The indicator gauge on all models uses a single
red light to indicate an overheated engine condition.
Engine Sender Unit Replacement
1.
Drain engine cooling system to a level below unit.
2.
Remove sender unit (located in the inlet manifold
near water pump housing on V-8 engines and in the
cylinder head near an exhaust port on L-6 engines)
and replace with new unit.
3.
Refill cooling system and check operation of unit.
CORVETTE INSTRUMENTS AND GAUGES
INDEX
Page
General Description ., 12-34
Service Operations . 12-35
Instrument Cluster ., 12-35
Fuel Gauge 12-35
Speedometer/Tachometer Service. 12-35
Temperature Gauge 12-35
Ammeter/Oil Pressure Gauges 12-35
GENERAL DESCRIPTION
All Corvette instruments and gauges are conveniently
located in the dash-mounted cluster. The entire cluster
is removable to permit servicing of the various instru-
ments and gauges. The indicator and cluster illuminating
bulbs may be replaced without removing the cluster from
the panel.
Regular maintenance is not required on the instrument
cluster or its components other than maintaining clean
and keeping the speedometer and tachometer cables
properly lubricated.
CHEVROLET CHASSIS SERVICE MANUAL