1967 CHEVROLET CAMARO fuel pressure

ENGINE FUEL 6M-11

dripping fuel, but a leak on the suction would not be ap-

parent except for its effect of reducing volume of fuel on

the pressure side.

1.
Tighten any loose line connections and look for bends

or kinks in lines.

2.
Disconnect fuel pipe at carburetor. Disconnect dis-

tributor to coil primary wire so that engine can be

cranked without firing. Place suitable container at

end of pipe and crank engine a few revolutions. If

little or no gasoline flows from open end of pipe then

fuel pipe is clogged or pump is inoperative. Before

removing pump disconnect fuel pipe at gas tank and

outlet pipe and blow through them with an air hose

to make sure they are clear. Reconnect pipes and

retest while cranking engine.

CAUTION: Whenever the engine is cranked re-

motely at the starter, with a special jumper

cable or other means, the primary distributor

lead must be disconnected from the negative

post on the coil and the ignition switch must be

in the "ON" position. Failure to do this will

result in a damaged grounding circuit in the

ignition switch.

3.
If fuel flows from pump in good volume from pipe

at carburetor, check fuel delivery pressure to be

certain that pump is operating withint specified limits

as follows:

a. Attach a fuel pump pressure test gauge to dis-

connect end of pump to carburetor pipe.

b.
Run engine at approximately 450-1,000 rpm (on

gasoline in carburetor bowl) and note reading on

pressure gauge.

c. If pump is operating properly the pressure will

be within specifications and will remain constant

at speeds between 450-1,000 rpm. If pressure

is too low, too high, or varies materially at dif-

ferent speeds, the pump should be replaced.

Removal

1.
Disconnect fuel inlet and outlet pipes at fuel pump.
Fig.
2P-Installing 283, 327, 350 V8 Engine Fuel Pump

2.
Remove fuel pump mounting bolts and remove pump

and gasket.

3.
On V8 engines; if push rod is to be removed, remove

pipe plug then remove push rod (396 and 427 cu. in.

engines), remove fuel pump adapter and gasket then

remove push rod (283 and 327 cu. in. engines).

4.
If a new fuel pump is to be installed, transfer

fittings.

Installation

1.
On V8 engines; if removed, install fuel pump push

rod and pipe fitting or fuel pump adapter. Use.

gasket sealer on gasket or pipe fitting.

2.
Install fuel pump using a new gasket and tighten

securely. Use sealer on fuel pump mounting bolt

threads.

NOTE:
On V8 engines, a pair of mechanical

fingers may be used to hold fuel pump push rod

up while installing fuel pump (fig. 2P).

3.
Connect fuel pipes to pump.

4.
Start engine and check for leaks.

CHEVROLET CHASSIS SERVICE MANUAL

SECTION 6T

AIR INJECTION REACTOR SYSTEM

INDEX

Page

General Description 6T-1

Maintenance Procedures 6T>1

Drive Belt. ...-..' 6T-1

Inspection 6T-1

, Adjustment . . 6T-1

Replacement 6T-1

Drive Pulley . . . . 6T-1

Replacement 6T-1

Pump Pulley ....................... 6T-1

Replacement. 6T-1

Air Manifold, Hose and Tube
...........>*.
6T-2

Inspection . . 6T-2

Replacement 6T-2

Check Valve (s) 6T-3
Page

Inspection 6T-3

Replacement . . 6T-3

Mixture Control Valve 6T-3

Inspection 6T-3

Replacement 6T-3

Air Injection Tube 6T-4

Inspection . . . ... . . . .... 6T-4

Replacement 6T-4

Air Injection Pump 6T-4

Inspection 6T-4

Replacement . 6T-4

Pressure Relief Valve Replacement 6T-4

Special Tools 6T-5

GENERAL

The Air Injection Reactor (A.I.R.) System (fig. 1) con-

sists of: the air injection pump (with necessary brackets

and drive attachments), air injection tubes (one for each

cylinder), a mixture control valve, check valves (one for

In Line engines, two for V8 engines) and air manifold as-

semblies, tubes and hoses necessary to connect the

various components.

Carburetors and distributors for engines with the

A.I.R. System are designed, particularly, for these en-

gines;
therefore, they should not be interchanged with or

replaced by a carburetor or distributor designed for an

engine without the A.I.R. System.

The air injection pump (fig. 2) picks up fresh filtered

air from the air cleaner, compresses the air and injects

it through the air manifolds, hoses and injection tubes

into the exhaust system in the area of the exhaust valves.

The fresh air ignites and burns the unburned portion of

the exhaust gases in the exhaust system, thus minimizing

exhaust contamination.

The mixture control valve (fig. 3) when triggered by a

sharp increase in manifold vacuum, supplies the intake

manifold with fresh filtered air to lean out the fuel-air
DESCRIPTION

mixture and prevent exhaust system backfire.

The check valve(s) prevent exhaust gases from entering

and damaging the air injection pump, as back flow can

occur even under normal operating conditions.

When properly installed and maintained, the A.I.R.

System will keep exhaust emissions well below require-

ments. However, if any A.I.R. component or any engine

component that operates in conjunction with the A.I.R.

system should malfunction, the exhaust emissions might

be increased.

Because of the relationship between "Engine Tune

Up"
and "Unburned Exhaust Gases", the condition of

Engine Tune Up should be checked whenever the A.I.R.

System seems to be malfunctioning. Particular care

should be taken in checking items that affect fuel - air

ratio such as the crankcase ventilation system, the

carburetor and the carburetor air cleaner.

Because of the similarity of many parts, typical illus-

trations and procedures are used except where specific

illustrations or procedures are necessary to clarify the

operation. For Repair Procedures on the Air Injection

Pump,
refer to the Passenger Chassis Overhaul Manual.

MAINTENANCE PROCEDURES

Drive Belt

Inspection

• Inspect drive belt for wear, cracks or deterioration

and replace if required.

• Inspect belt tension and adjust if below 50 lb. using a

strand tension gauge.

Adjustment

• Loosen pump mounting bolt and pump adjustment

bracket bolt.

• Move pump until belt is tight (55±5 lb. used belt or

75±5 lb. new belt using a strand tension gauge) then

tighten adjustment bracket bolt and mounting bolt.

CAUTION: Do not pry on the pump housing.

Distortion of the housing will result in extensive

damage to the Air Injection Pump.

Replacement

• Loosen pump mounting bolt and pump adjustment
bracket bolt then swing pump until drive belt may be

removed.

• Install a new drive belt and adjust as outlined above.

Drive Pulley .

Replacement

• Remove drive belt as outlined above then replace

drive pulley.

• Install and adjust drive belt as outlined above.

Pump Pulley

Replacement

• Hold pump pulley from turning by compressing drive

belt then loosen pump pulley bolts.

• Remove drive belt as outlined above then remove

pump pulley.

• Install pump pulley with retaining bolts hand tight.

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK AND EXHAUST SYSTEMS
8-8

CHEVELLE

FUEL TANKS

INDEX

Page

General Description.
g.g

Component Part Replacement
8-8

Fuel Tanks
. 8-8

Fuel Lines
8-8
Metering Units (Gauge, Sending Unit)

Fuel Tank Filler Neck Caps.
. .

Fuel Tank Vent Lines
Page

8-8

8-8

8-9

GENERAL DESCRIPTION

All models
use a 20
gallon capacity (approx.) fuel tank

mounted between
the
frame rails behind
the
rear axle.

The fuel tanks
are
basically
the
same
for
sedan, 2-seat

station wagon
and
pickup models except
for
filler neck

location
and
venting
(fig. 8).

All fuel tanks
are
vented
to the
atmosphere. Sedan

model tanks have
an
external vent hose and pipe assem-

bly
(fig. 11) and use a
non-vented fuel cap. Station wagon

and pickup model tanks
are
vented through
a
hose
and

vent pipe assembly
to the
filler neck
(fig. 8)
and
use a

vented, anti-surge type
gas cap. The
fuel caps
are two

different designs conforming
to SAE
standards
and are

not interchangeable.

The filler neck assembly
on
sedan models
is a
rear

fill design located behind
the
center
bar of the
bumper.
Station wagon
and
sedan pickup model filler neck assem-

blies
are
located
in
the left rear quarter panel.

The fuel pickup pipe
is
built integrally with
the
tank

gauge, located
at the
top-front center
of
the tank.
A
fine

mesh screen
is
located
at
the bottom-end
of the
fuel pick-

up pipe
to
prevent
the
entrance
of
foreign material into

the fuel system.

The sedan fuel tanks
are
held
in
place
by
two metal

straps attached individually
to the
underbody
at
each
end.

The straps hinge
at the
forward end and secure
the
tank

at
the
rear with
an
adjustable bolt
and nut
assembly.

The station wagon
and
pickup models have
a
frame

mounted fuel tank secured with straps
to
front and rear

supports.

COMPONENT PART REPLACEMENT

FUEL TANK

Draining Tank

The absence
of a
drain plug
in the gas
tanks makes
it

necessary
to
siphon fuel from
the
tank when draining
is

needed. Refer
to the
recommended draining procedures

previously outlined under Chevrolet Models
in
this

section.

Removal
and
Installation (Sedan Models)

1.
Raise vehicle.

2.
Drain fuel tank.

3.
Disconnect fuel pickup line
and
gauge wires from

tank unit.

4.
Disconnect vent hose from tank.

5. Remove tank support straps and lower tank carefully.

6.
To
install, reverse
the
removal procedure.

Removal
and
Installation

(Station Wagon
and
Pickup)

1.
Follow Steps
1
thru
3
outlined under sedan models.

2.
Remove tank support straps.

3.
Remove frame screw attachments from
the
front

support
(fig. 8).

4.
Guide tank forward
and
remove.

5.
To
install, reverse removal procedure.

FUEL LINES

The fuel lines, extending from fuel tank toiiuelpump,

are routed
on the
underside
of the
underbody along
the

right side
of the
vehicle opposite
the
single exhaust
sys-

tem.
The
fuel lines should occasionally
be
inspected
for
leaks,
kinks,
or
dents.
If
evidence
of
dirt
is
found
in the

carburetor
or
fuel pump
on
disassembly,
the
lines should

be disconnected
and
blown
out.
Check
the
fuel tank

strainer
for
damage
or
omission. Fuel lines
are of 5/16"

diameter tubing with beaded type ends
for
connections
of

hoses.

FUEL PIPE RETAINER
CUP

Removal
and
Installation

If fuel pipes
and
retainer clips
are
removed, Tool

J-7777 should
be
used
to
install
new
retainer clips
(fig.

10).
After removal
of the old
clip from
the
frame, position

the
new
clip
in the
location
of the old
clip. Index
the

"blind rivet"
and
press hard (hand pressure should
do)

to expand rivet.

GAUGE UNIT
AND
FUEL STRAINER

Removal
and
Installation
(Fig. 11)

1.
Drain tank
to a
level below
the
unit.

2.
Disconnect fuel pickup line
and
gauge unit wire.

3.
Use
special Tool J-8950
to
remove
cam
lock.
Re-

move unit
and
rubber gasket.

CAUTION: Carefully remove unit
so as not to

damage screen
on the end of
the pipe.

4.
Clean screen
by
blowing
out
with compressed
air.

5. Reverse procedure
to
install.

FUEL TANK FILLER NECK CAPS

The fuel tank filler neck caps
are
non-vented with
an

anti-surge feature. Station wagons have vented caps.

(Refer
to
"Fuel Tank Vent Lines").

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK AND EXHAUST SYSTEMS 8-11

EXHAUST SYSTEMS

INDEX

Page

General Description 8-11

Component Part Replacement 8-12

Muffler Assembly 8-12

Exhaust Pipes. 8-12

Tail Pipes 8-12

GENERAL DESCRIPTION

V-8

VIEW C
VIEW D

(EXCEPT WAGON)

L-6
VIEW A

Fig.
13—Single Exhaust System

The single exhaust system used on all six cylinder

engine models consists of an exhaust pipe, muffler and

tail pipe (fig. 13), An exhaust crossover pipe is added on

V-8 engine single exhaust models to connect the exhaust

manifolds to the system. A dual exhaust system, availa-

ble on V-8 engine models includes two exhaust pipes,

mufflers, and tail pipes and attaching hardware (fig. 14).

All systems are suspended on brackets with insulators

for rattle free operation.

The mufflers are a seam rolled construction with spot

welded baffles, with a capacity for muffling the exhaust

and at the same time, minimizing back pressure for
maximum engine efficiency. The internal parts of the

muffler are spot welded in position while external parts

are electric arc-welded to eliminate a chance of pre-

mature failure or rattle.

The exhaust system center mounting at the muffler lo-

cation (fig. 13) consists of an underbody bracket, an insu-

lator and a clamp. The clamp holds the muffler and tail

pipe with a "U" bolt and at the same time secures the

muffler and pipe to the body.

The exhaust system mounting at the end of the tail pipe

secures the pipe to a bracket assembly and insulator at-

tached to an existing underbody bracket (fig. 13).

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK AND EXHAUST SYSTEMS 8-16

EXHAUST SYSTEMS

INDEX

Page

General Description 8-16 Exhaust Pipes.

Component Part Replacement . 8-17 Tail Pipes. . .

Muffler Assembly 8-17
Page

8-17

8-17

GENERAL DESCRIPTION

Fig.
19-Cheyy If—Single Exhaust Systems

The single exhaust system on Chevy II models for six

cylinder engines (fig. 19) consists of an exhaust pipe,

muffler and tail pipe. On V-8 engines with single exhaust

assemblies (fig. 19) an exhaust crossover pipe is added

to connect the right exhaust manifold to the system. A

dual exhaust system (fig. 20), available on the V-8 engine

(except station wagons) includes two exhaust pipes,

mufflers, tail pipes with resonators and attaching

hardware.

The assemblies are secured to the engine at the ex-

haust manifolds, to the center mounting at the muffler
location and adjacent to the gas tank at the end of the

tail pipe. The assemblies are suspended on brackets with

insulators for rattle free operation.

The muffler is an all-welded construction with a ca-

pacity for muffling the noise and at the same time,

minimizing back pressure for maximum engine ef-

ficiency. The internal parts of the muffler are spot

welded in position while external parts are electric are

welded to eliminate a chance of premature failure or

rattle.

The exhaust system center mounting at the muffler lo-

cation consists of an underbody bracket, an insulator and

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK
AND
EXHAUST SYSTEMS
8-18

CORVETTE

FUEL TANK

INDEX

Page

General Description.
. 8-18

Service Operations
8-18

Fuel Tank
8-18

Gauge Sending Unit
8-20

Fuel Lines.
8-20

GENERAL DESCRIPTION

20 GALLON TANK

Fig.
21
—Corvette Fuel Tanks

The Corvette
is
equipped with
a
standard
20
gallon

(approx.) tank
or an RPO 36
gallon (approx.) fiberglass

tank
(fig. 21). The
tanks
are
installed
at the
very rear

of
the
vehicle, convenient
for
direct fuel filling into
the

tank.
The
tanks
are
held
in
place
by
two metal straps
at-

tached individually
to a
removable
gas
tank frame
sup-

port.
Two
guides
at the end of
the straps
are
adjustable

for securing
the
straps onto
the
tank support. The tank

support
is
secured
to the
frame rail with flat washers,

lockwashers, bolts
and
nuts.
The
tanks' rest
on six
felt

anti-squeak pads.
One pad
centers
on the
rear frame

crossmember
and one at
each side
on the
same cross-

member.
At the
same rear location two pads
are
placed

on
the
tank
at the
metal support strap (rear) attachment
location
and
another anti-squeak
pad
cemented
on the

support
at
the front
of
the tank.

The fuel tanks
are
equipped with
a gas
gauge metering

unit,
a
fuel pickup, fuel strainer
and
vent line.
If it be-

comes necessary,
the
tank
can be
completely drained
by

removing
the
fuel pickup hose which
is
located
at
the
bot-

tom
of the
tank,
or
by removing the metering
for
quicker

draining.

A pressure vacuum type, positive vented design
cap,

conforming
to
I.C.C. regulations,
is
used on both regular

production
and
optional fuel tanks.
The cap is
inter-

changeable with past model tanks
for
service replace-

ment purposes.

SERVICE OPERATIONS

FUEL TANK

CAUTION:
IF THE GAS
TANK SHOULD
BE

REMOVED
AND
INSTALLED, CARE SHOULD

BE EXERCISED
TO
AVOID PUNCTURING,

DROPPING
OR
DENTING
THE GAS
TANK.

Removal
(20
Gallon Tank)

WARNING: FIRST REMOVE BATTERY

CABLE.
1.
Remove
the
spare tire from tire carrier.

2.
Remove spare tire carrier bolted attachments
and

carrier
(fig. 22).

3.
Remove
the "U"
bolt attachments
at
both rear tail

pipe
(See
Figure
23).

4.
Separate
the
exhaust system
at
the transmission sup-

port crossmember
by
loosening
the "U"
bolt nuts.

5. Remove both rear muffler brackets from
the
frame

and slide
the
muffler system rearward.

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK
AND
EXHAUST SYSTEMS
8-24

EXHAUST SYSTEMS

INDEX

Page

General Description. ..........
8-24

Service Operations
8-24

Muffler Assembly.
8-24

Side Mounted Exhaust.
. . . 8-25

GENERAL DESCRIPTION

Fig.
30—Standard Dual

All Corvettes
are
equipped with dual exhaust systems

(fig.
30).
Each exhaust assembly
is
connected
to its own

exhaust manifold
and
carries
the
exhaust gases
to the

rear, discharging them
on
each side
of
the rear bumpers.

The dual exhaust system includes
two
front
and
rear

exhaust pipe sections, mufflers, tail pipes and attaching

hardware.
The
system
is
suspended
on
brackets with

insulators
for
rattle free operation. Adjustment
is
only

required
at the
rear muffler bracket.
In addition
to the
regular dual system
an
optional side

mounted, off-road exhaust system
is
available
as an
RPO

(fig.
31).
Extending between front
and
rear wheels,
the

dual units
are
mounted outboard
of the
frame side rails

at
the
rocker panel level,
and
completely replaces
the

regular dual assemblies*

Flow characteristics
are
improved and back pressures

reduced
by
the more direct exhaust routing and
by the use

of chambered pipes
for
sound muffling
in
place
of con-

ventional mufflers.

SERVICE OPERATIONS

Proper relationship
of
parts
is
necessary
in the ex-

haust system
for
carefree operation. Annoying rattles

are usually
a
result
of
incorrect alignment
of
the exhaust

system
due to
incorrect clearances.

MUFFLER ASSEMBLY

Replacement (Also Rear Exhaust
and
Tail Pipes)

Remove
"U"
bolt attachments
at
both rear tail pipe

shields.
2.

crossmember

1.
Separate
the
exhaust system
at the

tube
by
loosening the
"IT"
bolt nuts.

3.
Remove both rear muffler brackets from
the
frame

and slide
the
muffler system forward.

CAUTION: Before cutting
the
rear exhaust

pipe, measure service muffler exhaust pipe
end

and make certain
to
allow
1 1/2" for
engage-

ment
of the
rear exhaust pipe into service
muf-

fler pipe.

CHEVROLET CHASSIS SERVICE MANUAL

FUEL TANK
AND
EXHAUST SYSTEMS
8-31

EXHAUST SYSTEMS

INDEX

Page

General Description
8-31

Component Part Replacement
8-31

Muffler Assembly
8-31

Exhaust Pipe
. 8-31

Tailpipe and/or Resonator
8-32

GENERAL DESCRIPTION

The single exhaust system
cm
six* cylinder engine

models
(fig. 36)
consists
of an
exhaust pipe, extension,

muffler
and
tailpipe with necessary attaching brackets

and clamps.
On V-8
engine models with single exhaust

assemblies
(fig. 36) an
exhaust crossover pipe
is
added

to connect
the
right exhaust manifold
to the
system.
The

dual exhaust system available
on V-8
engine models
(fig.

37) includes
two
front exhaust pipes -with
or
without

resonators,
two
rear exhaust pipes, dual inlet-outlet

muffler, tailpipes and attaching hardware.

The assemblies
are
secured
to the
engine
at the ex-

haust manifolds,
to the
rear compartment pan reinforce-

ment ahead
of
axle
and
adjacent
to the gas
tank
at the
end
of the
tailpipe.
The
assemblies
are
suspended
on

brackets with insulators
for
rattle free operation.

The muffler
is an
all-welded construction with
a

•
capacity
for
muffling
the
noise
and at the
same time,

minimizing back pressure
for
maximum engine effici-

ency.
The
internal parts
are
electric welded
to
eliminate

premature failure
or
rattle.

The exhaust system center mounting
at the
muffler

location consists
of an
underbody bracket,
an
insulator

and
a
clamp.
The
clamp holds
the
muffler and tailpipe

with
a
"U" bolt and
at
the same time secures
the
muffler

and pipe
to the
body.

The exhaust system mounting
at the
end
of
the tailpipe

secures
the
pipe
to a
bracket assembly
and
insulator

attached
to an
existing underbody bracket.

COMPONENT PART REPLACEMENT

EXHAUST PIPE

Replacement

1.
Loosen
"U"
bolt clamp
at
rear exhaust pipe

connection.

2.
Remove exhaust pipe
to
manifold attaching nuts,
ex-

tension
and.
packing then separate pipe from manifold

studs.

NOTE:
Right exhaust crossover pipe
on V-8

engine single exhaust models
is an
integral part

of
the
exhaust pipe assembly and
is not
serviced

separately.

3.
Separate front exhaust pipe from rear exhaust pipe

extension.

4.
To
install exhaust pipe, connect pipe
to
rear exhaust

pipe extension
or
resonator
and
secure
to
exhaust

manifold. Note clearances
for
the standard and auto-

matic control linkages, underbody
and
crossmember.

5. Tighten exhaust pipe
to
manifold attaching nuts
and

rear "U" bolt clamp nuts.

EXHAUST PIPE EXTENSION

Replacement

1.
Remove "U" bolt clamps
at
muffler inlet and exhaust

pipe
or
resonator connections.

2.
Disconnect exhaust pipe extension
at
muffler
and

exhaust pipe
or
resonator connection.
3.
To
install extension, connect extension
to
exhaust

pipe
or
resonator and
to
muffler.

4.
Install
"V"
bolt clamps
and
tighten clamp nuts.

MUFFLER ASSEMBLY

Replacement

1.
Remove "U" bolt clamp
at
muffler inlet.

2.
Remove tailpipe support clamp.

3.
Separate muffler from rear exhaust pipe
and
remove

muffler from vehicle.

4.
If
usable,
cut
tail pipe from muffler.

5. Connect muffler inlet
to
exhaust pipe and install
"U"

bolt clamp
at
muffler inlet.

6. Connect tailpipe
to
muffler outlet
and
install rear

support clamp.

7. Install
"U"
bolt clamp
at
tailpipe
to
muffler outlet

connection and tighten nuts.

TAILPIPE

Replacement

1.
Remove
"U"
bolt clamp
at
muffler outlet.
If
replac-

ing right tail pipe, eut pipe
at
muffler outlet.

2.
Remove tail pipe rear hanger clamp and detach pipe

from muffler.

&IS SBtVKE MANUAL