ESP inoperative CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

Page 323 of 659


AIR INJECTOR REACTOR SYSTEM
6T-3

MIXTURE

CONTROL

VALVE

SIGNAL

PUMP PRESSURE

(MIXTURE VALVE INLET)

PUMP PRESSURE

(AIR MANIFOLD INLET)

IN LINE
AIR INJECTION

PUMP INLET

MIXTURE

CONTROL

VALVE

SIGNAL

MIXTURE

CONTROL

VALVE

OUTLET

MIXTURE

CONTROL

VALVE

INLET
AIR INJECTION

PUMP INLET

V8 (TYPICAL)
PUMP PRESSURE

(AIR MANIFOLD INLET)

MIXTURE CONTROL

VALVE INLET

MIXTURE CONTROL

VALVE SIGNAL

AIR INJECTION

PUMP INLET

PUMP PRESSURE^

(AIR MANIFOLD

J

MIXTURE CONTROL

VALVE OUTLET
V8 (396-427)

Fig.
4—Air Manifold Hose and Tube Routing (Typical)
a straight pipe thread.
Do
not use
a 1/4"
tapered

pipe
tap. The
hoses
of
the
Air
Injection Reactor

System
are a
special material
to
withstand high

temperature.
No
other type hose should
be

substituted.

• Install
new
hose(s) and/or tube(s), routing them
as

when removed.

• Tighten
all
connections.

NOTE:
Use
anti seize compound
on
threads
of

the
air
manifold
to
exhaust manifold
or
cylinder

head connections.

NOTE:
On
Chevy
n
vehicles equipped with
a

V8 engine,
the air
injection tubes
are
part
of the

air manifold
and
care must
be
used
in
removing

them from
the
exhaust manifold.
It may be

necessary
to
remove
the
exhaust manifold
and

use penetrating
oil on the
injection tubes before

the
air
manifold can
be
removed.

Check Valve

Inspection


The
check valve should
be
inspected whenever
the

hose
is
disconnected from
the
check valve
or
when-

ever check valve failure
is
suspected. (A pump that

,
had
become inoperative and had shown indications
of

having exhaust gases
in the
pump would indicate

check valve failure)..

• Orally blow through
the
check valve (toward
air

manifold) then attempt
to
suck back through check

valve. Flow should only
be in one
direction (toward

the
air
manifold).

Replacement

• Disconnect pump outlet hose
at
check valve. Remove

check valve from
air
manifold, being careful not
to

bend
or
twist
air
manifold.

Mixture Control Valve

Inspection

• Check condition
and
routing
of all
lines especially

the signal line.
A
defective signal
or
outlet line will

cause malfunctioning
of the
mixture control valve.

• Disconnect pump
to
valve inlet hose
at
pump.

• Leaking valve will
be
indicated
by an air
gushing

noise coming from
the
hose. Place palm
of
hand over

hose; little
or no
pull with
a
gradual increase
is

normal.
If
immediate strong pull
is
felt
or air
noise

is heard, valve
is
defective
and
should
be
replaced.

• Open
and
close throttle rapidly.
Air
noise should
be

evident
and
then gradually decrease. Check
for

proper valve usage.
If
strong pull
is not
felt
im-.

mediately
or air
noise
is not
present, valve
is not

functioning properly and should be replaced.


A
noisy valve should be replaced.

Replacement

• Disconnect
the
signal line,
air
inlet
and air
outlet

hoses then remove
the
valve.

• Install
new
valve
and
connect
air
outlet,
air
inlet

and signal line hoses.

CAUTION: Mixture control valves, though

similar
in
appearance
are
designed
to
meet

particular requirements
of
various engines,

therefore,
be
sure
to
install
the
correct valve.

CHEVROLET CHASSIS SERVICE MANUAL

Page 616 of 659


ACCESSORIES 15-7

6. The car begins to descend a hill--car speed in-

creases slightly and the regulator movements oc-

curing above occur again except in reverse. The

rubber drum is turned further against spring tension

and the air bleed orifices are uncovered more. This

bleeds more air to the Servo reducing the vacuum in

the unit. The diaphragm moves away from the

vacuum port, closes the throttle slightly, and with-

draws the tapered needle from the vacuum orifice.

With the orifice enlarged, the increased vacuum

counteracts the increased air bleed and the dia-

phragm finds a balance again at a reduced throttle

opening.

7.
Driver accelerates by pressing accelerator pedal-

car speed increases and the system responds by

moving the diaphragm to decrease throttle opening.

Since a bead chain is used, the chain merely relaxes

and has no effect on throttle operation. After the

driver releases pressure from the pedal, the throttle

will close until car speed decreases to the pre-set

speed. At that point the Regulator bleeds less air

to the Servo which opens the throttle enough to

maintain the pre-set speed. The system returns to a

stable condition.

8. Driver desires higher controlled speed, presses ac-

celerator until new speed is reached, and depresses

Engagement Switch fully and releases button--speed

sensing assembly tries to turn in a direction that

would decrease the throttle opening until the driver

fully depresses the Engagement Switch. Then the

current is cut off to the solenoid which retracts; the

solenoid nose expands the "U" clip releasing its

grip on the rubber drum. The drum and disk as-

sembly then rotates to a new position because of the

higher car speed. When the solenoid retracts, it also

shuts off vacuum to the Servo and opens the vacuum

port to atmospheric pressure within the Regulator

thereby bleeding down the Servo toward idle throttle

position. As the driver releases the Engagement

Switch, the contacts cause "pull in" and "hold in" of

the solenoid respectively. The system is engaged to
maintain the car speed at the time of Engagement

Switch release.

9. Driver desires lower cruising speed, presses En-

gagement Switch fully, waits until car speed de-

creases to desired speed then releases Switch--when

the Engagement switch is fully depressed the sole-

noid is de-energized causing the vacuum switch to

bleed down the Servo to idle throttle position and the

"U"
clip of the idle bleed valve is released from the

rubber drum. The drum and disk assembly is free

to rotate to a position which corresponds to vehicle

speed as the car slows. When the driver releases

the Engagement Switch, the unit "pulls in" and "holds

in" in the normal manner. The air bleed valve is

clutched to, the rubber drum at the car speed during

switch release. Vacuum is again applied to the

Servo and throttle control is assumed by the Regu-

lator to maintain the car speed at the time of switch

release.

10.
With system in operation, driver applies brakes--

simultaneously the Vacuum Release and Electric

Release Switches operate. The Vacuum Switch

bleeds air into the Servo through the air bleed line

coming from the Regulator. The vacuum is reduced

in the Servo and the throttle returns to idle position.

The Electric Release Switch cuts off power to the

entire system and the solenoid is de-energized. If

the driver removes his foot from the brake pedal the

Electric Switch again feeds voltage to the Engage-

ment Switch and the Vacuum Switch seals the air

bleed line. If the vehicle speed is above 20 mph

when this occurs, reduced voltage will flow to the

solenoid through the 40 ohm wire which will not be

sufficient to "pull in" the unit. If vehicle speed is

below 20 mph no current will flow since the tang

on the rubber drum has opened the low limit switch

points in the Regulator. In either case, after de-

pressing the brake pedal, the system will not con-

trol car speed until the driver operates the engage-

ment switch above 20 mph.

SERVICE OPERATIONS

The components of the Cruise Master system are de-

signed to be replaced should they become inoperative.

The Regulator is calibrated in such a manner during

manufacturing that overhaul operations are impractical.

However, one adjustment may be made to the Regulator to

correct speed drop or increase at the time of

engagement.

BRAKE RELEASE SWITCHES

ELECTRIC

Service — An inoperative switch must be replaced.

Switch replacement is identical to standard brake lamp

switch replacement.

Adjustment- The brake switch plunger must clear the

pedal arm when the arm is moved 1/4 inch measured at

the switch (Figure 7).

VACUUM

Service

An inoperative (sticking, plugged, or leaking)

switch must be replaced. Switch replacement is similar
to brake switch replacement. Be certain that the hose to

the switch is connected firmly and is not cracked or

deteriorated.

Adjustment- The brake switch plunger must clear the

pedal arm when the arm is moved 5/16 inch measured at

the switch (Figure 7).

ENGAGEMENT SWITCH

Service

replacement.
The engagement is serviced only by

Removal

1.
Pry the engagement button out of the turn signal knob

with a small thin bladed screwdriver (Figure 2).

2.
With a small hook or long nosed pliers, remove the

switch retaining ring.

3.
.Pull switch outward utilizing the slack in the wiring

harness.

4.
With a small soldering iron, unsolder the wires and

resolder them to the correct terminals of the re-

placement switch.

CHEVROLET CHASSIS SERVICE MANUAL