check engine light CHEVROLET CAMARO 1967 1.G Chassis Owner's Guide

CLUTCH AND TRANSMISSIONS
7*30

V-8 Models-With Uni-Directional Linkage

1.
Remove air cleaner.

2.
Disconnect accelerator linkage at carburetor.

3.
Disconnect accelerator return and TV rod return

springs.

4.
With right hand, pull TV upper rod forward until

transmission is through detent. With left hand, open

carburetor to wide open throttle position. Carbure-

tor must reach wide open throttle position at the

same time the ball stud contacts end of slot in upper

TV rod.

5. Adjust swivel on end of upper TV rod to obtain set-

ting described in Step 4. Allowable tolerance is

approximately 1/32".

6. Connect and adjust accelerator linkage as described

in Section 6.

7. Check for throttle linkage freedom.

Neutral Safety Switch Adjustment

The adjustment at the neutral safety switch is de-

scribed in the Electrical Section 12.

Throttle Return Check Valve (Dashpot) Adjustment

The adjustment of the throttle return check valve is

described in Section 6M for each carburetor installation.
Fig.
12PG - Floor Mounted Control Lever and

Bracket Assembly (Chevrolet Shown)

COMPONENT PARTS REPLACEMENT

TRANSMISSION REPLACEMENT (EXC. CORVETTE)

Removal

1.
Raise car on hoist (preferably) or on stand jack and

remove oil pan drain plug to drain oil.

NOTE:
If desired, the oil may be drained after

transmission removal.

2.
Disconnect the oil cooler lines (external cooled

models), vacuum modulator line and the speedometer

drive cable fitting at the transmission. Tie lines

out of the way.

3.
Disconnect manual and TV control lever rods from

transmission.

4.
Disconnect propeller shaft from transmission.

5. Install suitable transmission lift equipment to jack

or other lifting device and attach on transmission.

6. Disconnect engine rear mount on transmission ex-

tension, then disconnect the transmission support

crossmember and slide rearward.

7. Remove converter underpan, scribe flywheel-con-

verter relationship for assembly, then remove the

flywheel-to-converter attaching bolts.

NOTE:
The "light" side of the converter is

denoted by a "blue" stripe painted across the

ends of the converter cover and housing. This

marking should be aligned as closely as possible

with the "white" stripe painted on the. engine

side of the flywheel outer rim (heavy side of

engine) to maintain balance.

8. Support engine at the oil pan rail with a jack or other

suitable brace capable of supporting the engine

weight when the transmission is removed.
9. Lower the rear of the transmission slightly so that

the upper transmission housing-to-engine attaching

bolts can be reached using a universal socket and a

long extension. Remove upper bolts.

CAUTION: Oh V-8 engines, care must be taken

not to lower rear of transmission too far as the

distributor housing may be forced against the

dash causing damage to the distributor. It is

best to have an assistant observe clearance of

all upper engine components while the trans-

mission rear end is being lowered.

10.
Remove remainder of transmission housing-to-

engine attaching bolts.

11.
Remove the transmission by moving it slightly to the

rear and downward, then remove from beneath the

car and transfer to a work bench.

NOTE:
Observe converter when moving the

transmission rearward. If it does not move

with the transmission, pry it free of flywheel

before proceeding.

CAUTION: Keep front of transmission upward

to prevent the converter from falling out. Install

converter Tool J-9549 (or a similar tool con-

structed as shown in Figure 13PG, or, in an

emergency, a length of strong wire may be used)

immediately after removal from the engine.

Installation

NOTE:
The "light" side, of the converter is

denoted by a "blue" stripe painted across the

ends of the converter cover and housing. This

marking should be aligned as closely as possible

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-32

21.
Remove transmission output shaft slip yoke and in-

sert a plastic shipping plug in end of extension to

prevent spillage of transmission fluid.

NOTE:
The yoke is removed to avoid tearing

the heat reflecting pad on the underbbdy, when

the transmission is being removed.

22.
Remove bright metal ignition shielding from dis-

tributor area.

23.
Remove the transmission dip stick and tube

assembly.

24.
Disconnect transmission vacuum modulator line at

distributor advance line tee.

25.
Position transmission hoist under transmission and

attach safety chain to transmission.

26.
Remove transmission converter housing-to-engine

attaching foolts and slide transmission rearward.
NOTE:
Observe converter when moving trans-

mission rearward. If converter does not move

with the transmission, pry it free of flywheel

before proceeding.

27.
Install converter retaining strap.

28.
Lower and remove transmission from vehicle by

tilting the front down and to the right while inter-

mittently lowering the transmission to facilitate its

• removal.

29.
Reinstall transmission assembly by performing the

above steps in reverse order.

Bolt Torques

Transmission Case to Flywheel

Housing Bolts 35 ft. lbs.

Converter to Flywheel Bolts. . , . . 35 ft. lbs.

OTHER SERVICE OPERATIONS

Although certain operations, such as oil pan or gasket

replacement, valve body, governor, filler pipe "O" ring,

speedometer drive gear, case extension "0" ring and

rear oil seal, vacuum modulator, and servo cover or

gasket service may be performed from underneath the
vehicle without removing the Powerglide; their service

procedure is covered in the Passenger Overhaul Manual

and is not repeated here. Refer to the- Powerglide Sec-

tion of the Passenger Overhaul Manual for all other

service operations not covered here.

DIAGNOSIS

Proper operation of the Powerglide transmission may

be affected by a number of factors, all of which must be

considered when trouble in the unit is diagnosed.

Proper trouble diagnosis can only be accomplished

when performed in a thorough step by step procedure.

The following procedure has been devised and tested and

is recommended for all trouble diagnosis complaints and

if the service man will follow this checking procedure,

accurate and dependable diagnosis may be accomplished.

This will result in a savings of time, not only to the

service man, but to the customer as well.

WARMING UP TRANSMISSION

Before attempting to check and/or correct any com-

plaints on the Powerglide transmission it is absolutely

essential that the oil level be checked and corrected if

necessary. An oil level which is either too high or too

low can be the cause of a number of abnormal conditions

from excessive noise to slippage in all ranges.

It must be remembered that cold oil will slow up the

action of the hydraulic controls in the transmission. For

this reason a trouble or oil leak diagnosis should not be

attempted until the transmission has been warmed up by

either of the following procedures:

Shop Warm Up

1.
Connect tachometer to engine.

2.
Set parking brake tight and start engine.

3.
Place selector light in
"D"
(drive) range.

4.
Adjust carburetor idle speed adjusting screw to run

engine at approximately 750 rpm and operate in this

manner for two minutes. At the end of two minutes

of operation, the transmission will be sufficiently

warmed up for diagnosis purposes.
NOTE:
At this point, readjust the engine idle

speed to 450-475 rpm in
"D"
range.

Road Warm Up

Drive the car approximately 5 miles with frequent

starts and stops.

NOTE:
At this point, make sure the engine idle

speed is set to 450-475 rpm in
"D"
range.

CHECKING FLUID LEVEL AND CONDITION

After transmission has been warmed up, check the

fluid level with the engine idling, parking brake set and

control lever in "N" (neutral). If the fluid level is low,

add fluid to bring level up to the full mark on gauge rod,

CAUTION: If fluid level is too high, fluid may

be aerated by the planet carrier. Aerated fluid

will cause turbulence in the converter which will

result in lost power, lower stall speed and lower

pressures in control circuits. Lower fluid level

to full mark, then shut off engine to allow air

bubbles to work out of fluid.

When checking oil level, aburned smell and discolora-

tion indicate burned clutches or bands and the transmis-

sion will have to be removed.

MANUAL LINKAGE

Manual linkage adjustment and the associated neutral

safety switch are important from a safety standpoint.

The neutral safety switch should be adjusted so that the

engine will start in the Park and Neutral positions only.

With the selector lever in the Park position, the park-

ing pawl should freely engage and prevent the vehicle

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-33

from rolling. The pointer on the indicator quadrant

should line up properly with the range indicators in all

ranges.

OIL LEAKS

Before attempting to correct an oil leak, the actual

source of the leak must be determined. In many cases

the source of the leak can be deceiving due to "wind flow1 f

around the engine and transmission.

The suspected area should be wiped clean of all oil

before inspecting for the source of the leak. Red dye is

used in the transmission oil at the assembly plant and

will indicate if the oil leak is from the transmission.

The use of a "black light"* to identify the oil at the

source of leak is also helpful. Comparing the oil from

the leak to that on the engine or transmission dip stick

(when viewed by black light) will determine the source

of the leak.

Oil leaks around the engine and transmission are gen-

erally carried toward the rear of the car by the air

stream. For example, a transmission "oil filter tube

to case leak" will sometimes appear as a leak at the

rear of the transmission. In determining the source of

an oil leak it is most helpful to keep the engine running.

The mating surfaces of servo cover, converter housing,

transmission case and transmission case extension

should be carefully examined for signs of leakage. The

vacuum modulator must also be checked to insure that

the diaphragm has not ruptured as this would allow trans-

mission oil to be drawn into the intake manifold. Us-

ually, the exhaust will be excessively smoky if the

diaphragm ruptures due to the transmission oil added to

the combustion. The transmission case extension rear

oil seal should also be checked. All test plugs should be

checked to make sure that they are tight and that there

is no sign of leakage at these points. The converter

underpan should also be removed. Any appreciable quan-

tity of oil in this area would indicate leakage at the pump

square seal ring, pump seal assembly, or pump bolt

sealing washers.

BASIC PRESSURE CHECKS

Four basic pressure checks are used for diagnosis and

operational checks for the Aluminum Powerglide trans-

mission. All checks should be made only after thoroughly

warming up the transmission.

• Wide Open Throttle Upshift Pressure.

• Idle Pressure in "Drive" Range.

• Manual "Low" Range Pressure.

• "Drive" Range Overrun (Coast) Pressure.

It is not recommended that stall tests be conducted

which would result in engine vacuum falling below 10" Hg.

Pressure gauge hose connections should be made at

the low servo apply (main line) test point (fig. 14PG).

Run the gauge line into the driving compartment by

pushing aside the mast jacket seal. The line out of the

way of the drivers feet and connect to pressure gauge

J-21867.

• Wide Open Throttle Upshift Pressure Check

Refer to the pressure check chart for upshift pressure
SERVO APPLY

PRESSURE

Fig.
14PG - Pressure Test Plug

points as indicated on the lower servo apply (main line)

gauge.

• Idle Pressure in "Drive" Range

In addition tp the oil pressure gauges, a vacuum gauge

is needed for this check.

With the parking brake applied and the shift selector

lever in "Drive", low servo apply (main line) pressure

should be as shown on the pressure check chart.

If pressures are not within these ranges, the following

items should be checked for oil circuit leakage:

1.
Pressure regulator valve stuck.

2.
Vacuum modulator valve stuck.

3.
Hydraulic modulator valve stuck.

4.
Leak at low servo piston ring (between ring and

bore).

5.
Leak at low servo piston rod (between rod and bore).

6. Leak at valve body to case gasket.

7.
Leak at valve body gaskets.

8. Front pump clearances.

9. Check passages in transmission case for porosity.

• Manual "Low" Range Pressure Check

Connect a tachometer, apply the parking brake, place

the selector lever in "Low" range, and adjust the engine

speed to 1000 rpm with the car stationary.

Low servo apply (main line) pressure should be as

shown on the pressure check chart.

Pressures not within this range can indicate the fol-

lowing possibilities:

1.
Partially plugged oil suction screen.

2.
Broken or damaged ring low servo.

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-37

LI.
- LI Range can be selected at any vehicle speed,

and the transmission will shift to second gear

and remain in second until vehicle speed is re-

duced to approximately 40 MPH, .depending on

axle ratio. LI Range position prevents the trans-

mission from shifting out of first gear.
It is very important that any communication concerning

the Turbo Hydra-Matic always contain the transmission

serial number and that all transmission parts returned

to Chevrolet Motor Division always be tagged with the

transmission serial number.

MAINTENANCE AND ADJUSTMENTS

TRANSMISSION FLUID

Transmission fluid level should be checked with trans-

mission warm and selector lever in "P" Park position,

every time engine oil level is checked or as specified in

Section 0 when engine oil is changed.

CAUTION: Since the Turbo Hydra-Matic trans-

mission is very sensitive to oil level, special

precautions should be taken when checking the

oil level, to insure against an overfifE

Transmission fluid should be changed as specified in

Section 0.

FLUID LEVEL INDICATOR

The fluid level indicator is located in the filler pipe at

the right rear corner of the engine. To bring the fluid

level from the add mark to the full mark add 1 pint.

Fluid level should be to the full mark with transmission

at normal operating temperature. With cold fluid the

level should be at the add mark or slightly below.

SHIFT CONTROL LINKAGE ADJUSTMENT

Adjust linkage as shown below and in Figure 2.

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 selector 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.

See schematic diagram.

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

Steps 2 and 6. -

l(h Readjust indicator needle if necessary to agree with

the transmission detent" positions. See Section 9.

11.
Readjust neutral safety switch if necessary to pro-

vide the correct relationship to the transmission de-

tent positions. See Section 12.

12.
When properly adjusted the following conditions must

be met by manual operation of the steering column

shift lever:

a. From reverse to drive position travel, the trans-

mission detent feel must be noted and related to

indicated position on dial.

b.
When in drive and reverse positions, pull lever

rearward (towards steering wheel) and then re-

lease. It must drop back into position with no

restrictions.

NEUTRAL SAFETY SWITCH ADJUSTMENT

The neutral safety switch must be adjusted so that the

car will start in the park or neutral position, but will not

start in the other positions. For replacement refer to

Section 12 of this Manual.

DRAINING AND REFILLING TRANSMISSION

Drain oil immediately after operation before it has had

an opportunity to cool.

To drain oil proceed as follows:

1.
Remove bottom pan attaching screws, pan, and gas-

ket.

2.
Remove oil strainer. Remove "O" ring seal from

pick-up pipe and discard.

3.
Discard strainer if dirty.

4.
Install new "O" ring seal on pick-up pipe and install

strainer and pipe assembly.

5.
Thoroughly clean bottom pan.

6.. Affix new gasket to bottom pan with petroleum jelly.

7.
Install bottom pan with attaching screws and torque

to specifications;

8. If only the pan has been removed, pour approximately

7-1/2 pints of fluid into the transmission. If the

valve body has also been removed use 9-1/2 pints.

After a complete overhaul approximately 19 pints

are required. Be sure container, spout, or funnel is

clean.

9. Start engine and let idle (carburetor off fast idle

step).
Place selector lever in P position and apply

hand brake.

10.
With transmission warm (approximately 150°F), add

fluid to bring level to full mark on indicator.

CAUTION: Do not overfill. Foaming will re-

sult.

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-41

CAUTION: Use converter holding ToolJ-5384

when lowering transmission or keep rear of

transmission lower than front so as not to lose
converter.

The installation of the transmission is the reverse of

the removal.

TURBO HYDRA-MATIC DIAGNOSIS PROCEDURE

Accurate diagnosis of transmission problems begins

with a thorough understanding of normal transmission

operation. In particular, knowing which units are in-

volved in the various speeds or shifts so that the specific

units or circuits involved in the problem can be isolated

and investigated further. Analytical diagnosis will pro-

tect the technician from come backs and certainly will

improve owner satisfaction.

An important and often overlooked aspect of diagnosis

is finding out specifically what the customer is com-

plaining of. For this purpose a short ride with the cus-

tomer will often prove beneficial. It may be found that

the condition the customer wants corrected is standard

and should not be altered.

The following sequence, based on field experience, pro-

vides the desired information quickly and in most cases

actually corrects the malfunction without requiring the

removal of the transmission. Details of the items listed

in this sequence are covered further in the text.

SEQUENCE FOR TURBO HYDRA-MATIC

DIAGNOSIS PROCEDURE

1.
Check oil level and condition.

2.
Check and correct detent switch.

3.
Check and correct vacuum line and fittings.

4.
Check and correct manual linkage.

OIL LEVEL AND CONDITION CHECK

Always check the oil level before road testing. Oil

must be visible on dip stick prior to operating the ve-

hicle. Erratic shifting, pump noise, or other malfunc-

tions can in some cases be traced to improper oil level.

Oil level should be checked with the selector lever in

the Park (P) position, engine running, and the vehicle on

level pavement.

Fluid level should be to the FULL mark with the trans-

mission at normal operating temperature (170°-190°
F.).

With warm fluid (room temperature), the level should be

at or slightly below the ADD mark.

If oil level was low, refer to Oil Leaks.

The condition of the oil is often an indication of whether

the transmission should be removed from the vehicle, or

to make further tests. When checking oil level, a burned

smell and discoloration indicate burned clutches or bands

and the transmission will have to be removed.

MANUAL LINKAGE

Manual linkage adjustment and the associated neutral

safety switch are important from a safety standpoint

The neutral safety switch should be adjusted so that the

engine will start in the Park and Neutral positions only.

With the selector lever in the Park position, the park-

ing pawl should freely engage and prevent the vehicle

from rolling. The pointer on the indicator quadrant

should line up properly with the range indicators in all

ranges.
OIL LEAKS

Before attempting to correct an oil leak, the actual

source of the leak must be determined. In many cases,

the source of the leak can be deceiving due to "wind flow"

around the engine and transmission.

The suspected area should be wiped clean of all oil be-

fore inspecting for the source of the leak. Red dye is

used in the transmission oil at the assembly plant and

will indicate if the oil leak is from the transmission.

. The use of a "black light"* to identify the oil at the

source of leak is also helpful. Comparing the oil from

the leak to that on the engine or transmission dip stick

(when viewed by black light) will determine the source

of the leak.

Oil leaks around the engine and transmission are gen-

erally carried toward the rear of the car by the air

stream. For example, a transmission "oil filler tube to

case leak" will sometimes appear as a leak at the rear of

the transmission. In determining the source of an oil

leak it is most helpful to keep the engine running.

POSSIBLE POINTS OF OIL LEAKS

• 1. TRANSMISSION OIL PAN LEAK

a. Attaching bolts not correctly torqued.

b.
Improperly installed or damaged pan gasket.

c. Oil pan gasket mounting face not flat.

2.
REAR EXTENSION LEAK

a. Attaching bolts not correctly torqued.

b.
Rear seal assembly — damaged or improperly

installed.

c. Gasket seal — (extension to case) damaged or

improperly installed.

d. Porous casting.

3.
CASE LEAK

a. Filler pipe "O" ring seal damaged or missing;

misposition of filler pipe bracket to engine —

"loading" one side of
"O"
ring.

b.
Modulator assembly "O" ring seal
—
damaged or

improperly installed.

c. Governor cover, gasket and bolts — damaged,

loose; case face leak.

d. Speedo gear
—
"O" ring damaged.

e. Manual shaft seal — damaged, improperly in-

stalled.

f. line pressure tap plug — stripped, shy sealer

compound.

g. Parking pawl shaft cup plug
—
damaged, improp-

erly installed.

h. Vent pipe (refer to Item 5).

i. Porous case.

4.
FRONT END LEAK

a. Front seal - damaged (check converter neck for

nicks,
etc., also for pump bushing moved for-

ward);
garter spring missing from pump to con-

verter seaL

b.
Pump attaching bolts and seals
—
damaged, miss-

ing, bolts loose.

CHEVROLET a
SERVICE

STEERING
9-33

POWER STEERING

INDEX

Page

General Description
. 9-33

Maintenance
and
Adjustments
9-33

Bleeding Hydraulic System
9-33

Fluid Level
. 9-33

Adjustments
. 9-34

Power Steering Gear
. . 9-34

Pump Belt Tension
9-34
Hydraulic System Checks
9-34

Component Replacement
and
Repairs
. 9-35

Power Steering Pump.
. 9-35

Power Steering Gear
9-36

Control Valve
and
Adapter Assembly
9.35

Power Cylinder
9.37

Power Steering Hoses
9.39

GENERAL DESCRIPTION

Two types
of
power steering
are
used
for 1967.
One
is

the conventional linkage type
for
Chevy
n and
Corvette

vehicles
and the
other
is the
integral gear type
for

Chevrolet, Chevelle,
and
Camaro.
For
both types
the

hydraulic pressure
is
provided
by an
engine-driven vane-

type pump.

On
the
Chevy
n and
Corvette linkage type power steer-

ing, hydraulic pressure
is
delivered through
a
hose from

the pump
to a
valve which senses
the
requirement
for

power assistance
and
supplies
the
power cylinder
ac-

cordingly.
The
steering gear used with this power steer-

ing
is the
same basic unit used
on
manually steered

vehicles;
it is
serviced
as
outlined
in the
manual steering

part
of
this section except
for
adjustment, which
is

covered
in the
following pages.
The
steering linkage also

is serviced the same
as
manual counterparts.

The Chevrolet, Chevelle
and
Camaro integral gear type

power steering
has the
hydraulic pressure delivered

from
the
pump through two hoses
to the
steering gear.
In
the power steering gear
the
steering shaft, hydraulic

valve, worm, and rack-piston
nut are all in
line making
a

compact
and
space saving assembly.
All oil
passages
are

internal within
the
gear except
the
pressure
and
return

hoses.

The steering gear
is a
recirculating ball system
in

which steel balls
act as a
rolling thread between
the

steering worm
and
rack-piston
nut. The
rack-piston
nut

is
all one
piece
and is
geared
to the
sector
of
the piston

shaft.
The
valve
is
contained
in the
gear housing elimi-

nating
the
need
of
bolts
or
seals
to
attach
a
separate

valve housing.

The valve
is an
open-center, rotary-type three
way

valve.
The
spool
is
held
in
neutral position by means
of a

torsion
bar. The
spool
is
attached
by
means
of
the stub

shaft
to one end of the
torsion
bar
and
to the
valve body

on
the
other
end.
Twisting
of the
torsion bar allows
the

spool
to
move
in
relation
to the
valve body thereby oper-

ating
the
valve.

MAINTENANCE
AND
ADJUSTMENTS

BLEEDING HYDRAULIC SYSTEM

1.
Fill
oil
reservoir
to
proper level and
let oil
remain

undistrubed
for at
least two minutes.

2.
Start engine
and run
only
for
about
two
seconds.

3.
Add
oil if
necessary.

4.
Repeat above procedure until
oil
level remains
con-

stant after running engine.

5. Raise front
end of
vehicle
so
that wheels
are off
the

ground.

6. Increase engine speed
to
approximately
1500 rpm.

7. Turn
the
wheels
(off
ground) right
and
left, lightly

contacting
the
wheel stops.

8. Add
oil if
necessary.

9. Lower
the car and
turn wheels right and left
on the

ground.

10.
Check
oil
level and refill
as
required.

11.
If oil is
extremely foamy, allow vehicle
to
stand
a

few minutes with engine
off and
repeat above

procedure.
,

a.
Check belt tightness
and
check
for a
bent
or
loose

pulley. (Pulley should
not
wobble with engine

running.)
b.
Check
to
make sure hoses
are not
touching
any

other parts
of the car,
particularly sheet metal.

c. Check
oil
level, filling
to
proper level
if
neces-

sary, following operations
1
through
10.
This

step
and
Step
"D" are
extremely important
as

low
oil
level and/or
air in the oil are the
most

frequent causes
of
objectionable pump noise.

d. Check
the
presence
of air in the oil. If air is

present, attempt
to
bleed system
as
described
in

operations
1
through
10. If it
becomes obvious

that
the
pump will
not
bleed after
a few
trials,

proceed
as
outlined under Hydraulic System

Checks.

FLUID
LEVEL

1.
Check
oil
level
in the
reservoir
by
checking
the dip

stick when
oil is at
operating temperature.
On

Chevelle models equipped with remote reservoir,

the reservoir should
be
maintained approximately

3/4 full when
oil is at
operating temperature.

2.
Fill,
if
necessary,
to
proper level with
GM
Power

Steering Fluid
or, if
this
is not
available, automatic

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY AND CHASSIS 12-2

FJg.
1 - Fuse Panel Assembly

All power window and tailgate circuits require the igni-

tion switch to be "ON" to open or close the windows un-

like past model designs which were operated independ-

ently of the ignition switch.

The windshield wiper and washer switch is new in that

washer button in the center of the knob has been deleted
and its function will be accomplished by pushing the knob.

A set screw is used to retain the knob to the shaft.

In addition to fuses, the wiring harness incorporates

fusible links to protect the wiring. Links are used rather

than a fuse in wiring circuits that are not normally fused,

such as the ignition circuit. Fusible links in the Chevro-

let wiring are four gauge sizes smaller than the cable it

is designed to protect. The links are marked on the

insulation with wire gauge size because of the heavy insu-

lation which makes the link appear a heavier gauge than it

actually is.

Engine compartment wiring harness incorporate sev-

eral fusible links. Each link is identified with its gauge

size.
A fusible link is a length of special wire (normally

four wire gauges smaller than the circuit it is protecting)

used in wiring circuits that are not normally fused, such

as the ignition circuit. The same size wire with a spe-

cial hypalon insulation must be used when replacing a

fusible link.

The links are:

1.
The pigtail lead at the battery positive cable (except

Corvette) is a 14 gauge, brown fusible link protecting

the 10 gange battery charging circuit. This wire is

an integral part of the battery cable assembly and

servicing requires replacing the complete battery

cable assembly. On Corvette models this link is

installed as a molded splice at the solenoid "Bat"

terminal and servicing requires splicing in a new

link.

2.
A 16 gauge black fusible link is located at horn relay

to protect all unfused wiring of 12 gauge or larger.

It is a serviceable piece with an in-line connector

and is not integral with the wiring harness.

3.
The generator warning light and field circuitry (16

gauge wire) is protected by a fusible link (20 gauge

orange wire) used in the "battery feed to voltage

regulator #3 terminal" wire. The link is installed

as a molded splice in the generator and forward lamp

harness and is serviced by splicing in a new 20 gauge

wire as required.

4.
The ammeter circuit on all models is protected by

two orange, 20 gauge wire fusible links installed as

molded splices in the circuit at the junction block or

the solenoid "Bat" terminal (Corvette only) and at the

horn relay. Each link is serviced by splicing in a

new 20 gauge wire as required.

The wiring harnesses use a standarized. color code

common to all Chevrolet vehicles. Under the color code,

the color of the wire designates a particular circuit. The

harness title indicates the type of harness, single of mul-

tiple wire, and also describe the location of the harness.

The body harness is a flat, solid wire assembly and is

routed through the vehicle near the center of the body.

Composite wiring diagrams (figs. 104 thru 124) are in-

cluded at the end of this section.

MAINTENANCE AND ADJUSTMENTS

Maintenance of the lighting units and wiring system

consists of an occasional check to see that all wiring

connections are tight and clean, that the lighting units are

tightly mounted to provide good ground and that the head-

lamps are properly adjusted. Loose or corroded con-

nections may cause a discharged battery, difficult start-

ing, dim lights, and possible damage to generator and

regulator. Wire harnesses must be replaced if insulation

becomes burned, cracked, or deteriorated. Whenever it
is necessary to splice a wire or repair one that is bro-

ken, always use solder to bond the splice. Always use

rosin flux solder on electrical connections. Use insulat-

ing tape to cover all splices or bare wires.

When replacing wires, it is important that the correct

size be used. Never replace a wire with one of a smaller

size.

Each harness and wire must be held securely in place

by clips or other holding devices to prevent chafing or

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY AND CHASSIS 12-8

is inserted through radiator support opening.

Remove two screws retaining lamp assembly to

lower sheet metal.

Remove three screws retaining lamp assembly to

lender.

To replace lamp assembly, reverse removal proce-

dure and check operation of the unit.
is aligned with flat on pivot shaft. Install stop lock

bolt and torque bolt to 45-60 in, lbs. Make sure that

side-to-side panel alignment is not changed when in-

stalling and tightening the stop.

CAUTION: Do not exceed specified torque

when tightening stop lock bolt.

HEADLAMP PANEL REPLACEMENT-CORVETTE

Refer to Figure 13 for Panel Mounting details.

1.
Remove engine compartment hood as outlined in

Section 1.

2.
Actuate headlamp panel to the open position.

NOTE:
In the event headlamp motor is inop-

erative, manual positioning of the panel can be

accomplished by turning the knurled knob at in-

board end of motor. As an assist in manual

operation of panel, apply light hand pressure to

panel in desired direction of rotation.

3.
Remove positive lead from battery terminal.

4.
Remove headlamp bezel retaining screws and bezel.

5. Remove the sealed beam housing unit as an assem-

bly - disconnect sealed beam leads at harness con-

nector and remove connector from sealed beam

leads;
remove the housing-to-panel retaining screws

and remove housing unit and wiring from panel.

6. Remove motor from panel pivot shaft - see motor

removal procedure. Then remove the panel stop

from panel inboard pivot shaft, and disconnect switch

lead wires from panel, support-mounted motor

switch.

7. Remove the panel retaining bolt access hole plugs

from inside the panel then rotate panel as required

and remove the retaining bolts and slide supports

from ends of panel pivot shaft. Remove bearing, felt

seal, retainer and washer from inboard pivot shaft.

8. Remove panel from its location by alternately disen-

gaging pivots from their retaining slots and with-

drawing unit forward through opening in body (fig.

14).

9. Loosen alien screw in spacer and disassemble parts

from the panel outboard pivot shaft.

10.
Install washer, retainer, felt seal, bearing and

spacer, in that order, to panel outboard pivot shaft.

Do not tighten spacer on shaft at this time.

11.
Position panel in body opening and index panel pivot

shafts in retaining slots; then loosely install support

retaining bolts.

12.
Install washer, retainer, felt seal, bearing and sup-

port, in that order, to panel inboard pivot shaft, and

loosely install support retaining bolts. -

13.
Check side-to-side alignment of panel, making sure

that there is no panel-to-body contact; position

spacer snugly against bearing; then tighten spacer

seat screw to 30-50 in. lbs.

14.
Install stop on panel inboard shaft so that it rests

against bearing, being sure that index mark on stop
15.
Check and align panel to body as follows:

a. Tighten panel pivot support bolts snugly but still

allowing panel to" be moved by applying hand

pressure.

b.
Position panel to the closed position and align

with body so that all surfaces are flush.

c. With the panel in the closed position the outboard

access hole is aligned with the forward bolt head.

Tighten this bolt with the panel in the closed

position - access to bolt head can be obtained by

working through opening between the hood and

body.

d. Rotate panel to obtain access to each bolt head

and torque bolts to 100-140 in. lbs.

e. Connect switch lead wires to support-mounted

limit switch.

16.
Install seaLed beam housing unit and at the same time

position sealed beam lead wires through panel out-

board pivot shaft. Install housing unit retaining

screws and install lead wires in connector, making

sure to match colors between harness and connector.

17.
Install motor assembly - see motor replacement

procedure.

18.
Connect positive lead to battery terminal.

19.
Adjust headlamp panel as outlined under "Headlamp

Panel Travel Adjustment".

20.
Adjust headlamp aiming as outlined under "Headlamp

Adjustment".

21.
Install headlamp bezel and engine compartment

hood - refer to Section 1 for hood installation.

Fig.
14
- Headlamp Panel Removal (Corvette)

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY
AND
CHASSIS
12-26

•
Low oil
pressure

• High engine temperature

• Defective wiring
or
switch

connector from sender

in block above starter
on

and
at
left front
of
distributor
on V-8
Sending Unit Replacement

1.
Disconnect wiring harness

unit terminal (located

L-6 engines

engines).

2.
Remove sender unit using Tool J-21757
or 12
point

socket, replace with
new
unit
and
check operation.

GENERATOR INDICATOR

1.
Ignition
on,
Engine
not
Running
and
Telltale Light

Off.

• Indicator bulb burned out, replace bulb.

• Open circuit
or
loose connection
in the
telltale

light circuit.

2.
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, located
in the
instrument

panel, consists
of a
red light which will indicate
an
over-

heated 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
oh L-6
engines)

and replace with new unit.

3.
Refill cooling system
and
check operation
of
unit.

CHEVELLE INSTRUMENTS AND GAUGES

INDEX

Page

General Description
* *
i2-26

Service Operations
12-26

Instrument Panel
12-26

Instrument Cluster.
12-26

Fuel Gauge and/or Ammeter
12-27

Clock,
i 12-27

Speedometer
12-27
Page

Speedometer Cable
.
. 12-27

Temperature Gauge
12-29

Oil Pressure Gauge
12-29

Indicator Lights.
. 12-29

Oil Pressure Indicator
12-29

Generator Indicator
. . 12-29

• Temperature Indicator
12-29

GENERAL DESCRIPTION

The Chevelle instrument cluster assembly consists
of:

a speedometer;
a
fuel gauge;
a
generator,
an
engine
tem-

perature and an
oil
pressure indicator lamp, and includes

a clock
on
deluxe models.
On
super sport models,
am-

meter, coolant temperature
and oil
pressure gauges
re-

place
the
appropriate indicator lights. Except
for the

speedometer,
all of the
indicator lamps, instruments
and

gauges
of
these clusters may
be
serviced without remov-

ing
the
instrument cluster assembly from
the
vehicle.

In addition
to the
instrument indicator lamps,
a
brake

warning lamp
is
included
in the
cluster
as
standard

equipment.
The
indicator
is
connected
to the
parking
brake
and
brake pressure differential switches
and

serves
a
dual function.
It
lights when the parking brake

is applied
and
also when
the
brake pedal
is
applied,
if a

malfunction should occur
in the
brake system
due to a

loss
of
hydraulic pressure. Servicing
of the
hydraulic

pressure differential switch
is
covered
in
Section
5 of

this manual.

Regular maintenance
is not
required on the instrument

cjLuster
or its
components other than maintaining dean

and tight electrical connections, replacing defective parts

and keeping
the
speedometer cable properly lubricated.

SERVICE OPERATIONS

INSTRUMENT PANEL ASSEMBLY

INSTRUMENT CLUSTER (Figs.
41
thru
44)

Removal

1.
Disconnect battery ground cable.

2.
Remove steering coupling bolt and disconnect steer-

ing shaft from coupling.

3.
Loosen mast jacket lower clamp.

4.
Remove
air
conditioning center distributor duct
(if

so equipped).

5. Remove radio rear support bracket screw.

6. Remove mast jacket upper support clamp and retain-

ing bolts from lower support (refer
to
Section
9,

Steering).
CAUTION: Cover mast jacket
and
parl

brake handle with
a
suitable material
to
prevc

scratching.

7.
Disconnect speedometer cable
at
rear
of
cluster

housing
and
speed warning control knob
at
panel
(if

so equipped).

8. Remove instrument panel retaining screws (nine

upper and five lower).
.

9. Working under the console remove four lower retain-

ing screws from instrument cluster housing.

10.
Pull instrument panel assembly from console and
lay

forward on mast jacket.

11.
Disconnect wiring harness, cluster lamps and wiring

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