engine CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

SECTION 13

RADIATOR AND GRILLE

INDEX

Page Page

General Description 13-1 Repairs 13-4

Radiator and Shroud-All Vehicles (Except Corvette) . . . . 13-1 Installation 13-4

Removal 13-1 Grille Assembly - Chevy II 13-4

Installation 13-1 Removal . 13-4

Radiator and Fan Shroud - Corvette . . . . 13-1 Repairs 13-5

Fan Shroud Replacement 13-1 Installation . 13-5

Aluminum Radiator 13-1 Grille Assembly - Corvette 13-5

Copper Radiator . 13-1 Removal . . . . 13-5

Grille Assembly - Chevrolet 13-2 Installation ....*... 13-5

Removal 13-2 Grille Assembly - Caxnaro 13-5

Repairs 13-3 Removal 13-5

Installation 13-3 Repairs . 13-6

Grille Assembly - Chevelle 13-3 Installation . . 13-6

Removal 13-.Q

GENERAL DESCRIPTION

Radiator assemblies are attached by cap screws either the radiator and shroud are basically the same for each

to the radiator support or radiator shroud, depending on vehicle,

the engine installation of each vehicle. The Camaro fan

Shroud is mounted in two bottom slots and secured by one NOTE: Refer to the Fisher Body Service Man-

bolt at the top. Removal and installation procedures for ual for Body, Section IX for Sheet Metal, Section

14 for Bumpers, and Section 1A for Air Condi-

tioning information when required.

SERVICE OPERATIONS

RADIATOR
AND
SHROUD—ALL VEHICLES
NOTE: Reach upper two shroud bolts from top,

(EXCEPT CORVETTE)
between hood and radiator support. Reach lower

4 by reaching around front edge of open hood.

Removal

1.
Drain radiator. 4.- Remove shroud carefully (tilt rearward, then lift up

2.
Disconnect inlet and outlet radiator hoses, and Pow- to clear fan blades).

erglide cooler lines if vehicle is so equipped. 5. Reverse procedure to install, fill cooling system and

3.
Remove radiator and shroud attaching screws and lift check for leaks.

radiator and shroud out of vehicle.

Aluminum Radiator

Installation

NOTE:
Refer to Figures 1 through 5 for radi- Removal and Installation

ator fan and shroud assembled positions for each 1. Remove shroud as previously outlined.

vehicle. Reverse removal procedures, fill cool- 2. Disconnect lower raciiator hose at either end.

ing system and check for leaks. 3. Remove radiator upper mount bracket bolts and

bracket, then lift radiator from vehicle.

RADIATOR AND FAN SHROUD-CORVETTE 4. Reverse procedure to install.

Fan Shroud Replacement (Fig. 4) Copper Radiator

1.
Drain radiator and open hood. (Install a bolt in hole

of hood support bracket for safety purposes.) Removal and Installation

2.
Disconnect upper radiator hose and supply tank hose 1. Remove hood panel assembly after scribing bracket

at radiator connection. location.

3.
Remove shroud bolts. 2. Drain radiator and disconnect radiator hoses.

CHEVROLET CHASSIS SERVICE MANUAL

RADIATOR AND GRILLE 13-6

VIEW A
VIEW B

V-8 ENGINE
RADIATOR

FAN GUARD

(L-6 ENGINE)

VIEW

Fig.
5 - Radiator and Shroud - Camaro

grille header panel, catch support bracket, and radi-

ator support and remove hood catch.

Remove screws from each headlamp bezel and re-

move bezels from vehicle. Remove headlamps.

Remove hardware attaching hood catch support to

radiator support, valance panel, and lower grille

and remove catch support from vehicle.

Disconnect parking lamps. Remove rivets securing

center grille to upper and lower grilles and remove

center grille from vehicle. If necessary, replace

name plate.

Remove screws and rivets securing grille header

panel to fenders and upper grille and remove header

panel.

Remove hardware attaching upper and lower grilles

to vehicle and remove upper and lower grilles.

Remove screws attaching valance panel to fenders,

and fender extensions and retractable headlamp door
assemblies if so equipped, and remove valance panel

from vehicle.

10.
If vehicle is equipped with retractable headlamp cov-

ers,
disconnect electrical plugs. Remove screws at-

taching headlamp bracket assemblies to radiator

support and remove assemblies from vehicle.

Repairs

If any components removed are undamaged, they may

be used for the new grille installation. Where rivets were

removed, make new attachments using screws and nuts,

patent clips, or rivets.

Installation

Install grille and related components following the re-

moval procedure in reverse order. Refer to torque spec-

ifications in rear of manual for correct torque values.

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-2

GENERAL DESCRIPTION

The Cruise Master is a speed control system which

employs engine manifold vacuum to power the throttle

Servo unit. The Servo moves the throttle when speed

adjustment is necessary by receiving a varying amount

of bleed air from the Regulator unit. The Regulator

varies the amount of bleed air through a valve system

which is linked to a speedometer-like mechanism. The

speedometer cable from the transmission drives the

Regulator, and a cable from the Regulator drives the

instrument panel speedometer. The. engagement of the
Regulator unit is controlled by an Engagement Switch

located at the end of the turn signal lever. Two brake

release switches are provided: an Electric Switch dis-

engages the Regulator unit and a Vacuum Switch de-

creases the vacuum in the Servo unit to quickly return

the throttle to idle position.

The operation of each unit of the system and the

operation of the entire system under various circum-

stances is described below. Figure 1 shows the location

of the system components within the vehicle-

COMPONENT OPERATION

ENGAGEMENT SWITCH

This switch, located within the turn signal knob, has

three positions. In the fully released position, the switch

passes current through resistance wire to effect a "hold

in" magnetic field in the Regulator solenoid. This cur-

rent is sufficient only to hold the solenoid in place once

it has been actuated by the "pull in" circuit. Depressing

the button partially allows current to flow to the Regu-

lator solenoid at full voltage which causes the solenoid

to pull in. Depressing the button fully opens the circuit

to both the resistance and standard solenoid feed wires

and the solenoid becomes de-activated.

During vehicle operation the three switch positions

have the following functions:

Released

a. System not engaged: No function of the system

will occur although a small current is flowing

through the solenoid via the resistance wire (at

vehicle speeds over 20 mph).

b.
System engaged: The small current flowing

through the resistance wire is holding the solenoid

in the engaged position.

^r-WIRE RELIEF LUG

1 ^-#2-BLUE WIRE

L'3.BLACK WIRE
X /-TURN SIGNAL LEVER

SWITCH—^
^SN

RETAINING RING-^ %^

BUTTON -^

Fig.
2 - Cruise Master Engagement Switch
Partially Depressed

Full voltage is applied to the solenoid (vehicle speed

over 20 mph) which sets the Regulator to maintain the

vehicle speed at the time of Regulator engagement.

Fully Depressed

No electricity flows to the solenoid and the Regulator

is inactive. This position is used by the driver when he

desires to raise or lower his controlled speed. He may

accelerate to his new speed, press the button fully (Regu-

lator releases previously set speed) and release the but-

ton. Upon releasing the button, it passes through the

partially depressed position and the solenoid is "pulled

in", then into released position which provides "hold in"-

current. The driver may also press the button fully with

no pressure on the accelerator pedal. In this case the

regulator releases control of the throttle which returns

to idle and the car slows. When the button is released

the solenoid is pulled in and held in respectively and the

regulator resumes speed control at the speed of the

vehicle during the moment of button release (at vehicle

speeds over 20 mph).

LOCK
NUT

ORIFICE
TUBE

AND
CONNECTOR

ASSEMBLY

AIR FILTER AND

SOLENOID HOUSING COVER

Fig. 3 - Regulator Unit

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-3

CONTROLLED AIR SUPPLY

FROM REGULATOR
DIAPHRAGM

SPRING

METERING ROD

VARIABLE ORF1CE

ENGINE AAANIFOLD VACUUM

FROM REGULATOR VACUUM VALVE
BEAD CHAIN

VACUUM CHAMBER —*
MOUNTING SCREW

Fig.
4- Servo Unit

BRAKE RELEASE SWITCHES

Two brake release switches are employed in the Cruise

Master System. When the brake pedal is depressed, an

Electric Release Switch cuts off the voltage supplied to

the engagement switch, hence cuts off power to the Regu-

lator unit. The Regulator is then disengaged and requires

Engagement Switch operation to return it to operation.

A Vacuum Release Switch operates simultaneously with

the electric release switch whenever the brake pedal is

depressed. This switch opens a port to atmospheric

pressure which rapidly bleeds down the vacuum in the

Servo unit thereby returning the throttle to the idle

position.

SERVO UNIT

The Servo unit is a vacuum actuated, variable position

diaphragm assembly which operates the carburetor throt-

tle when the system is in operation (fig. 4). It is powered

by engine intake manifold vacuum and operates the throt-

tle linkage via a bead chain. The Servo has two ports on

the sealed side of the diaphragm housing: one is supplied

manifold vacuum, and the other is connected to a variable

air bleed in the Regulator Unit. The vacuum port is

located at the center of the unit and the air bleed port

is near the outer wall. When vacuum is applied to the
center port, atmospheric pressure moves the diaphragm

which pulls on the bead chain opening the carburetor

throttle. As the diaphragm moves, it positions a tapered

needle within an orifice in the vacuum port so that as the

diaphragm moves toward the port, the orifice becomes

smaller; and as it moves away from the port, the orifice

becomes larger.

The air bleed port serves to supply a variable quantity

of air to the diaphragm chamber which causes the dia-

phragm to attain a balanced state (between the force of

the atmospheric pressure to chamber pressure differ-

ential and the force of the diaphragm and throttle return

springs). In operation then, the following events occur:

Vacuum is applied to the center port and the diaphragm

moves toward the port. The tapered needle restricts

the vacuum port more and more as it moves into the

orifice. If no air was allowed to bleed into the chamber,

the diaphragm would move until it contacted the housing,

however, the Regulator meters bleed air into the chamber

and the diaphragm reaches a point at which the air is

bled out of the chamber through the vacuum port orifice

as fast as it enters the air bleed port. If the Regulator

begins to supply less bleed air, (vehicle speed decreas-

ing) the vacuum in the chamber increases and the dia-

phragm moves toward the vacuum port. In so doing, the

tapered needle closes the vacuum port orifice even more

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-4

Fig. 5 - Servo Mounting

and the air bled into the chamber again equals the air

bled out. A balance occurs again with the diaphragm in

a new position. If the Regulator begins to supply more

bleed air, (vehicle speed increasing) the vacuum in the

chamber drops and the diaphragm moves away from the

vacuum port, withdrawing the tapered needle from the

orifice and enlarging it. Since the vacuum orifice is

now larger, the greater quantity of air being bled into

the chamber may be bled out by vacuum and a balance

again occurs with the diaphragm in a new position.

AIR

TO SERVO

VACUUM

TO SERVO
VACUUM

RELEASE

SWITCH

ELEaRIC

RELEASE

SWITCH

Fig.
6- Servo, Regulator and Hose
Fig. 7 - Release Switches and Brackets

REGULATOR

The Regulator is a device which has two primary

functions: First, it is a vacuum switch which, when en-

gaged by the driver, supplies engine manifold vacuum to

the Servo. Second, it meters a small variable quantity

of air to the Servo unit in order to change the carburetor

throttle opening to effect speed control. A secondary

function of the Regulator is to drive the speedometer.

Since the car speed is sensed by a speedometer-like

mechanism within the unit, the speedometer cable from

the transmission drives the Regulator which drives a

second cable (at a one to one ratio) to the speedometer.

The Regulator is electrically engaged and disengaged

through operation of the Engagement Switch and the

Electric Brake Release Switch. It has two sub-assem-

blies which make up the unit: one being the magnetic

speed sensing assembly and the other being the solenoid

actuated vacuum switch, air bleed and filter, and low

limit speed switch assembly (fig. 8 and 9).

Magnetic Speed Sensing Assembly

The speed sensing assembly operates in the same man-

ner as a speedometer unit except that instead of rotating

a needle through an angle proportional to the vehicle

speed, it rotates a rubber drum which is clutched to the

air bleed valve when the system is in operation. The

assembly is driven by the speedometer cable from the

transmission which turns a disk shaped ferrite magnet.

Facing the magnetic disk is the driven brass disk mounted

on a shaft with the rubber drum mounted on the same

shaft. A spiral hairspring connects the shaft to the

housing and allows it to rotate through an angle which is

proportional to car speed. If the car doubled its speed,

the shaft would rotate to twice its previous angle as may

be seen by noting the operation of a speedometer. The

CHEVROLET CHASSIS SERVICE MANUAL

driven disk is sandwiched between the magnetic disk and

a field plate. The field plate forms a returning path for

the magnetic field from the magnetic disk.

The gear drive for the magnetic disk is a 90 degree

nylon gear drive with the driven gear rotating both the

magnetic disK and the speedometer drive cable.

Vacuum Switch, Air Bleed and Filter, and Low

Limit Speed Switch

The end of the shaft from the speed sensing assembly

with the rubber drum extends into the air bleed metering

assembly. This rubber drum has a tang extending from

its surface which allows a set of points to close at a

specific car speed. When the car reaches about 20 mph,

the rubber drum has rotated far enough (moved by the

brass driven disk in the magnetic field) so that its tang

has allowed a spring loaded electrical point to contact

another point. These points are in series with the sole-

noid coil so that under 20 mph, no Regulator operation

is possible.

Surrounding the rubber drum is a "U" shaped spring

clip which is held spread away from the drum by the

nose or cam of the solenoid when the solenoid is in the

relaxed position. The rubber drum and this clip com-

prise the speed clutch of the regulator. When the sole-

noid is energized, the solenoid nose moves toward the

drum and releases the ends of the clip. The clip springs

inward and attaches itself by friction to the drum. Now,
ACCESSORIES 15-5

any change in car speed will rotate the drum and move

the "U" clip just as a speedometer moves its needle.

The top of the MUtf clip is attached to the air bleed valve.

The clip moves a sleeve which slides on the orifice

tube thereby covering and uncovering air ports in the

wall of the tube (the tube inner end is plugged) whenever

car speed changes from the speed at which the solenoid

was energized. The direction of drum rotation is such

that resulting bleed valve operation will cause the Servo

to decrease engine power if the car exceeds the preset

speed and increase engine power if car speed decreases.

The air which passes out the orifice tube enters the

Regulator through the openings in the solenoid housing,

passes through the oil wetted polyurethane filter, and then

enters the orifice tube ports.

When the solenoid is de-energized, the nose retracts

and cams the ends of the "U" clip outward so that it re-

leases the rubber drum.

The solenoid also operates a vacuum switch simul-

taneously with the clutching and declutching of the "U"

clip.
The vacuum switch supplies the Servo unit with

manifold vacuum. The solenoid operated vacuum valve

slides over two ports in the Regulator wall. One port

is connected to manifold vacuum and the other is con-

nected to the center port of the Servo unit. When the

solenoid is de-energized, the valve closes the manifold

vacuum port and opens the Servo port to the inside of

the regulator case. When the solenoid is energized, the

valve connects the Servo port to the manifold vacuum

AAAGNET

SPEED CUP

FIELD PLATE

HAIRSPRING
TO SPEEDOMETER

MAGNET HOUSING

ASSEMBLY
ORIFICE TUBE &

CONNECTOR ASSEM.
CONTROL

VALVE

CLUTCH

SPRING

LOW LIMIT

SPEED SWITCH

RUBBER

DRUM

VACUUM PORT

TO SERVO

INPUT CONNECTION

SOLENOID COIL

SOLENOID AND CLUTCH

HOUSING ASSEMBLY
VACUUM PORT

TO ENGINE

VACUUM VALVE

UNLOCKING CAM

•SOLENOID PLUNGER

AIR FILTER

SIDE VIEW SECTION

REGULATOR DISENGAGED
END VIEW SECTION

ENGAGED

Fig.
8 - Regulator-Cross Section '

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-9

Adjustment- Adjust the bead chain so that it is as tight

as possible without holding the throttle open when the

carburetor is set at its lowest idle throttle position.

When connecting the bead chain (engine stopped) manually

set the fast idle cam at its lowest step and connect the

chain so that it does not hold the idle screw off the cam.

If the chain needs to be cut, cut it three beads beyond the

bead which pulls the linkage.

REGULATOR

Service - A defective regulator, that is one which is not

simply out of adjustment, must be replaced. During re-

placement, check the hoses which connect to the regulator

and replace any which are cracked or deteriorated.

Air Filter

The air filter located in the solenoid cover should be

cleaned and re-oiled at engine oil change intervals.

1.
Snap the solenoid cover off.

2.
Remove the filter and wash it in kerosene or mineral

spirits. Squeeze it dry and wet with SAE 10 engine

oil.
Squeeze out excess oil and reinstall into the

cover.

3.
Attach the cover with neoprene seal to the solenoid

housing. Be certain that the cover fits tightly to the

housing.

One regulator adjustment is possible: Engagement-

Cruising Speed Zeroing (to remove any difference be-

tween engagement and cruising speed).

NOTE:
No regulator adjustment should be

made, however, until the following items have

been checked or serviced:

1.
Bead chain properly adjusted.

2.
All hoses in good condition, properly attached, not

leaking, not pinched or kinked.

3.
Regulator air filter clean and properly oiled.

4.
Electric and vacuum release switches properly

adjusted.

Engagement—Cruising Speed Zeroing

If the cruising speed is lower than the engagement

speed, loosen the orifice tube locknut and turn the tube

outward; if higher, turn the tube inward. Each 1/8 turn

will alter the engagement-cruising speed difference one

mph. Tighten the locknut after adjustment and check the

system operation at 50 mph.

ELECTRICAL SYSTEM CHECK OUT

1.
Check fuse and connector.

2.
Check electric brake switch as follows: Unplug con-

nector at brake switch. Connect ohmmeter at points

A and B on brake switch. The ohmmeter must indi-

cate infinity when the brake pedal is depressed and

continuity when pedal is released. The cruise re-

lease brake switch (electric) is adjusted as is the

standard stop light brake switch. Replace electric

brake switch if needed.

3.
Check engagement switch and connecting wiring as
follows: Unplug push button control connector

(brown, blue, black) at electrical wiring harness con-

nector and perform the following tests. (See Fig-

ure 10)

Test #1
—
Connect ohmmeter between terminal #1 (brown

wire) and terminal #2 (blue wire). Continuity shall be

maintained until switch is depressed all the way in.

Test #2
—
Connect ohmmeter between terminal #1 (brown

wire) and terminal #3 (black). No continuity shall be

shown; however, when the button is depressed halfway,

continuity shall be indicated. When the button is pressed

all the way down, no continuity shall be shown.

Test #3 — Connect ohmmeter between terminal #2 (blue

wire) and terminal #3 (black). Button released, no con-

tinuity; however, when the button is depressed partially

and fully, continuity shall be shown.

4.
Check regulator solenoid coil, low-speed switch, and

wiring harness as follows:

a. Disconnect engagement switch wire harness con-

nector from the main wire harness connector

(brown, blue, and black wires). Connect ohm-

meter
'
between point C (blue wire in main wire

harness) and ground. (Make sure the regulator is

well grounded to chassis.) The ohmmeter should

read 45 ohms ± 2 ohms. If a resistance of

greater value is shown, then disconnect the con-

nector from the regulator and measure the re-

sistance of the blue wire from point C to D. It

should measure 40 ohms. Check the resistance

from point E (vertical bar of terminal forming T)

to ground. It should measure 5 ohms ± 1/4 ohm.

Replace either the wiring harness or solenoid as

needed if greater values are indicated. The black

harness wiring from point F to G should also be

checked for continuity.

ENGAGEMENT SWITCH TEST

BUTTON POSITION

Cruise (released)

Engage (partially depressed)

Trim (fully depressed)
TERMINALS

1 TO 2

closed

Closed

open
1 TO 3

open

closed

open
2 TO 3

open

closed

closed

SERVO AND VACUUM SYSTEM CHECK OUT

To determine the condition of the diaphragm, remove

hoses from power unit and apply 14 inches of vacuum to

either vacuum tube opening (seal the other opening) and

hold in for one minute. The vacuum shall not leak down

more than 5 inches of vacuum in one minute. If leakage

is detected, replace servo. To utilize engine as a vac-

uum source, proceed as follows:

1.
DISCONNECT SERVO $EAD CHAIN and hoses from

servo and connect engine vacuum directly to vacuum

servo fitting (fitting in middle of servo). Seal the

servo unit opening.

2.
Note position of servo diaphragm.

3.
Start engine - the diaphragm should pull in.

4.
Clamp off engine vacuum supply line and check for

leakage. '

The cruise release brake switch (vacuum) and connecting

hoses can likewise be checked using a vacuum pump.

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-11

12 VOLTS D.C.
ELECTRIC BRAKE

RELEASE

IGNITION

SWITCH

ENGINE

VACUUM

TRANSDUCER

Fig.
11 - Vacuum and Electrical Diagram

AUTOMATIC LEVEL CONTROL

INDEX

Page

General Description . . 15-11

System Checks and Adjustments 15-13

Service Operation . 15-15

GENERAL DESCRIPTION

A pneumatic level control system that automatically

maintains correct rear trim height of a car under varying

load conditions, the optional automatic level control is

used only in conjunction with the Superlift Shock Absorber

option.

The Superlift Shock Absorber option alone, consists of

the two shock absorbers with pressure lines to a "Tee"

where a ill valve is located, the shocks are inflated

with (or deflated of) compressed air (at any gas station)

to obtain the vehicle level desired with any given load

change.

The automatic leveling system is added to the Superlift

Shock Absorbers and supplies its own compressed air.

The system (fig. 13) consists of a vacuum operated air

compressor with pressure regulator,
and
integral storage

tank, vacuum line to engine, air intake filter, air lines,

and a height control valve.

The COMPRESSOR is a two-stage, vacuum actuated

type, requiring no lubrication. Vacuum supply is taken

from engine carburetor base. High pressure air is
supplied to the reservoir tank by the second stage of

the two-stage compressor. The first stage intake stroke

draws air at atmospheric pressure through a oneway

check valve located in the end of the first stage housing

under the first ^tagei housing cover. On the first stage

compression stroke, the intake valve is closed and the

oneway check valve in the second stage end of the piston

is opened. This allows the air from the first stage

cylinder to flow through the hollow piston into the second

stage cylinder for jhigh pressure compression. The

second stage compression stroke closes the check valve

in the piston and opeijis the check valve in the end of the

second stage housing.

The intake and compression strokes are controlled by a

sliding distributor valive that is actuated through an arm

that is tripped by the piston as it nears the end of each

stroke. Each time the arm actuates the distributor

valve, a different set of holes are covered in the first

stage housing. The distributor valve controls the flow of

intake manifold vacuum and air under atmospheric pres-

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-13

SYSTEM TEST
CHECKS AND ADJUSTMENTS

Automatic Level Control Test Gauge (Fig. 15)

A complete system test includes on and off-the-car

component tests.. '

On the car tests are:

Quick check of Automatic Level Control System

Compressor output test

Regulator test and adjustment

Control valve test

Time delay test

Line and fitting leak test

Trim adjustment

Off-the-car operations include:

Control valve replacement

Compressor repair

Component leak tests

a. Compressor, reservoir, and regulator

b.
Control valve

c. Superlifts

Quick Check-On Car (Reservoir Pressure at 150 PSI)

1.
Fill the fuel tank or simulate at the rate of 6 lbs./

gal.
- otherwise car should be empty.

2.
Turn engine off.

3.
Add a 2 passenger load to the rear bumper or tail-

gate.
Maintain the load until the -car lifts or AT

LEAST 20 SECONDS.

4.
After car lifts remove the load and observe until the

car lowers.

FILL VALVE

J-21999

CONNECTORS

Fig.
15 - Test Gauge Set J-22124
NOTE: To service the Automatic Level Con-

trol it will be necessary to secure Gauge Set

J-22124 or make up the following test gauge. If

the connectors indicated are not readily avail-

able others may be substituted.

1.
Collect the following parts:

a. Fill Valve, J-21999.

b.
A tee which has three 1/8M female taper pipe

threads.

c. An adapter which has a 1/4" female taper pipe

thread on one end and a 1/8" male taper pipe

thread on the other end.

d. Air Pressure Gauge, J-4872.

e. Two metal sleeves, rubber seals and tube nuts.

f. A length of 1/8" tubing. ~

g. Two male connectors which have a 1/8" male

taper pipe thread on one end and a 3/8-24 straight

thread male fitting on the other end.

2.
Assembly

a. Connect Fill Valve, J-21999, (female end) at male

connector 3/8-24 straight thread fitting.

b.
Connect other end of male connector to tee.

c. Connect adapter to tee.

d. Connect pressure regulator to adapter.

e. Connect second male connector to tee, (1/8 inch

male pipe thread fitting).

f. Install tubing to connector; other end of tubing

will go on unit to be checked.

NOTE:
Make certain all fittings are air tight.

Compressor Output Test—On Car

1.
With all accessories off, run the engine until fast idle

screw is off the fast idle cam. Turn off ignition.

2.
Deflate system through service valve, then remove

high pressure line at regulator adapter and connect

test gauge.

3.
Inflate reservoir to 70 psi through service valve.

4.
Observe test gauge for evidence of compressor air

leak.

5.
If leaking, proceed to leak test-compressor reser-

voir, and regulator. If not leaking, continue this

test.

6. With engine running at slow idle, observe reservoir

build-up for five minutes. Reservoir pressure should

build up to a minimum of 90 psi.

7.
If compressor fails to cycle, make sure the vacuum

and air intake lines are open and unobstructed before

removing compressor for repair.

8. If build-up is too slow, proceed to repair com-

pressor.

9. Satisfactory build-up indicates system problem to be

in the control section. However, again observe the

test gauge for evidence of an air leak and proceed

accordingly.

Regulator Test and Adjustment

Performance test the regulator with a known good com-

pressor on the car. *

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-14

Deflate system through service valve and disconnect

line at pressure regulator valve. Install test gauge on

regulator valve high pressure fitting.

Inflate system through service valve to maximum

available pressure.

NOTE: If available pressure is less than 140

psi,
start engine to build-up reservoir to this

pressure.

Regulated pressure should build-up to and hold

steady at 100-130 psi on test gauge.

Check regulated pressure by momentarily (not more

than one second) depressing valve core on test gauge

arid observe gauge reading.

If regulated pressure now reads less than 100 psi,

replace regulator assembly.

If regulated pressure exceeds 130 psi, replace regu-

lator assembly.

Control Valve Test

Exhaust (Superlifts Inflated)

1.
Disconnect control valve lever from link.

2.
Hold lever down in exhaust position until Superlifts

deflate or for a minimum of 18 seconds.

3.
If Superlifts deflate, perform Intake Check.

4.
If Superlifts do not deflate, remove exhaust adapter

from control valve and hold lever down as in Step 2.

Replace adapter, O-ring and filter if this deflates

Superlifts.

5.
Replace control valve if none of the above steps solve

problem.

Intake (Reservoir Pressure 125 psi Minimum)

1.
Disconnect overtravel lever from link.

2.
Hold lever up in intake position until Superlifts in-

Fig.
16 - Assembly Leak Test Preparation
flate or for a minimum of fifteen seconds.

3.
If Superlifts inflate and hold, proceed to Time Delay

Check. '•

4.
If Superlifts inflate and then leak down, perform leak

test on lines and fittings and then on Superlifts and

control valve. Repair or replace as indicated.

Time Delay Test (Reservoir Pressure 125 psi Minimum)

1.
Record rear trim height of empty car (rear bumper

to ground).

2.
Add weight equivalent to two passenger load to rear

of car. Car should begin to level in 4-18 seconds.

3.
Remove weight. After 4-18 seconds car should begin

to settle.

4.
Replace valve if time delay is not within the 4-18

seconds.

Trim Adjustment—On Car

Trim adjustment should be performed with a full fuel

tank (or the equivalent in load at the rate of 6 lbs
./gal-

lon)
,
but no other load.

Abbreviated Adjustment

1.
Fill the compressor at the service valve with the

available air line pressure.

2.
Disconnect link from height control valve lever.

Move the height control valve lever upward until air

fills the Superlifts.

3.
Move lever downward and hold until air stops escap-

ing from the exhaust port of the height control valve.

The Superlifts will now automatically hold 8 to 15

PSI.
;

4.
Let lever go to its neutral position> and loosen the

lever adjustment nut.

5.
Assemble the link to the height control valve lever

and tighten the lever adjustment nut.

NOTE: Do not move control valve lever and

overtravel body while tightening nut.

Leak Tests

Compressor, Reservoir and Regulator

1.
Remove assembly intact.

2.
Connect test gauge to regulator. Inflate reservoir

through service valve to 80-110 psi.

3.
Route an 8" rubber hose between vacuum and vent

ports,
(fig. 16).

4.
Submerge in water and observe for air leaks at:

Reservoir weld seam.

Reservoir to compressor O-ring.

Regulator to compressor O-ring.

Regulator boot-defective internal.O-rihg.

Diaphragm between first and second stage housings.

' Tightening through bolts may correct the leak.

Cover gasket and retainer screw. A few bubbles here

is not a leak. A continuous stream indicates defec-

tive compressor check valves.

Service valve.

Test gauge connections.

5.
Correct any leaks detected by either tightening

screws or replacing parts.

CHEVROLET CHASSIS SERVICE MANUAL