fuel pressure CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

HEATER AND AIR CONDITIONING 1A-30

Leak Detector

Tool J-6084 (fig. 43) is a propane gas-burning torch

which is used to locate a leak in any part of the system.

Refrigerant gas drawn into the sampling tube attached to

the torch will cause the torch flame to change color in

proportion to the size of the leak. Propane gas fuel

cylinders used with the torch are readily available

commercially throughout the country.

CAUTION: Do not use lighted detector in any

place where combustible or explosive gases,

dusts or vapors may be present;

Operating Detector

1.
Open control valve only until a low hiss of gas is

heard, then light gas at opening in chimney.

2.
Adjust flame until desired volume is obtained. This

is most satisfactory when blue flame is approxi-

mately 3/8" above reactor plate. The reaction plate

will quickly heat to a cherry red.

3.
Explore for leaks by moving the end of the sampling

hose around possible leak points in the system. Do

not pinch or kink hose.

NOTE: Since R-12 is heavier than air, it is

good practice to place open end of sampling tube

immediately below point being tested, partic-

ularly in cases of small leaks.

CAUTION: Do not breathe the fumes that are

produced by the burning of R-12 gas in the de-

tector flame, since such fumes can be toxic in

large concentrations of R?»12.

4.
Watch for color changes. The color of the flame

which passes through the reaction plate will change

to yellow when sampling hose draws in very small

CHIMNEY

REACTION PLATE

BURNER HEAD

Fig.
43—Leak Detector
leaks of R-12. Large leaks will be indicated by a

change in color to a vivid purplish-blue. When the

sampling hose passes the leak, the flame will clear

to an almost colorless pale-blue again. If the flame

remains yellow when unit is removed from leak,

insufficient air is being drawn in or the reaction

plate is dirty.

NOTE: A refrigerant leak in the high pressure

side of the system may be more easily detected

when, if possible, the system is in operation. A

leak on the low pressure side may be most

easily detected after the engine has been shut

off for several minutes to allow system pres-

sures to equalize. This particularly applies to

the front seal.

VACUUM PUMP

A vacuum pump should be used for evacuating air and

moisture from the air conditioning system.

Vacuum pump, Tool J-5428, (fig.. 44) is available for

this purpose. It is used as a component part of the

Charging Station J-8393, described previously. The fol-

lowing precautions should be observed relative to tbe

operation and maintenance of this pump.

' • Make sure dust cap on discharge outlet of vacuum

pump is removed before operating.

• Keep all openings capped when not in use to avoid

moisture being drawn into the system.

• Oil should be changed after every 250 hours of nor-

mal operation.

To change oil, simply unscrew hex nut located on

back side of pump, tilt backward and drain out oil

(fig. 44). Recharge with 8 ounces of vacuum pump

oil.
If you desire to flush out the pump, use this

same type clean oil. Do not use solvent.

NOTE: Improper lubrication will shorten the

life of pump.

• If this pump is subjected to extreme or prolonged

cold, allow it to remain indoors until oil has reached

approximate room temperature. Failure to warm oil

will result in a blown fuse.

• A five ampere time delay cartridge fuse has been

installed in the common line to protect the windings

of the compressor. The fuse will blow if an ex-

cessive load is placed on the pump. In the event the

fuse is blown, replace with a five ampere time delay

fuse - do not use a substitute fuse as it will result in

damage to the starting windings.

• If the pump is being utilized to evacuate a burnt-out

system, a filter must be connected to the intake

fitting to prevent any sludge from contaminating the

working parts, which will result in malfunction of the

pump.

• Do not use the vacuum pump as an air compressor.

AVAILABILITY OF REFRIGERANT-12

Refrigerant-12 is available through Parts Stock in 25

lb.
drums and in 15 oz. disposable cans. Valves are

available for
the"
disposable cans, which may be used as

individual cans or as a group of up to four cans (fig. 45).

Tool J-6272 is used with one through four cans. The

use of the four-can fixture makes it possible to charge

the system with a known quantity of refrigerant without

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-6

CHOKE VALVE

COMPLETELY

CLOSED

PULL UPWARD ON

ROD TO END OF

TRAVEL

BEND ROD

TO ADJUST
ROD IN BOTTOM

OF SLOT

BOTTOM OF

ROD SHOULD

EVENWITH

TOP OF

HOLE
CHOKE VALVE

CLOSED

BOTTOM OF

ROD SHOULD

BE EVEN WITH

TOP OF HOLE

TOP OF ROD

SHOULD BE EVEN

WITH BOTTOM

OF HOLE (CHOKE

CLOSED)

^..BEND ROD TO

ADJUST

_PULL DOWNWARD

ON ROD TO CON-

TACT STOP

L6 (TYPICAL)

V8 327-275 HP

V8 350-295 HP
BEND ROI

TO ADJUST

PULL UPWARD ON

ROD TO CONTACT

STOP ON BRACKET

ALL V8 (EXCEPT 327-275 HP

AND 350-295 HP)

Fig.
11 - Remote Choke Adjustment

sequence outlined on Torque Sequence Chart. A slight

leak at the intake manifold destroys engine performance

and economy.

Service Fuel Lines and Fuel Filter

1.
Inspect fuel lines for kinks, bends or leaks and cor-

rect any defects found, • • •

2.
Inspect filter and replace if plugged.

NOTE:
If a complaint of poor high speed per-

formance exists on the vehicle, fuel pump tests

described in Section 6M should be performed.

Service Cooling System

1.
Inspect cooling system for leaks, weak hoses, loose

hose clamps and correct coolant level, and service

as required.

NOTE:
A cooling system pressure test, as de-

scribed in "Additional Checks and Adjustments"

in this section, may be performed to detect

internal or external leaks within the cooling

system.

Check and Adjust Accelerator Linkage

1.
Disconnect accelerator rod at carburetor throttle

lever.

2.
Hold carburetor throttle lever in wide position.

3.
Pull accelerator rod to wide open position. (On ve-

hicles equipped with automatic transmission, pull

through detent).

4.
Adjust accelerator rod to freely enter hole in carbu-

retor throttle lever.'

NOTE:
Accelerator linkage is outlined in de-

tail in Section 6M.
5. Connect accelerator rod at throttle lever.

Service Crankcase Ventilation (Fig. 10}

All engines have either "Positive" or "Closed Positive"

ventilation systems utilizing manifold vacuum to draw

fumes and contaminating vapors into the combustion

chamber where they are burned. Since it affects every

part of the engine, crankcase ventilation is an important

function and should be understood and serviced properly.

In both "Positive" and "Closed Positive" ventilation,

air is drawn through the engine, (through a regulating

valve) into the manifold, drawing' crankcase vapors and

fumes with it to be burned. "Positive" ventilation uses a

vented-meshed cap for clean air intake to the engine,

while . "Closed Positive" ventilation system draws the

clean air from the carburetor air cleaner and has a

nonvented oil filler cap.

1.
Ventilation valve may be checked as outlined under

"Additional Checks and Adjustments".

2.
Inspect for deteriorated or plugged hoses.

3.
Inspect all hose connections.

4.
On closed positive ventilation systems, remove flame

arrestor and wash in solvent then dry with com-

pressed air.

Service Air Injection Reactor System

Inspect air injection reactor system for evidence of

leaks,
deteriorated hoses, cracked air manifolds or tubes

and loose hose clamps. Inspect air injection pump belt

condition and tension. Make all necessary repairs as

outlined in "Section 6T".

Because of the relationship between "Engine Tune Up"

and "Unburned Exhaust Gases", the condition of Engine

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-11

Fig.
18 - Cooling System Pressure Test

Carburetor

Refer to Section 6M to perform adjustments such as

idle vent, float level, pump rod and secondary valve.

Fuel Pump

If the owner has complained of poor high speed per-

formance, the fuel pump may be at fault. Too low a

pump pressure or volume will cause a high speed "miss"

because of lack of fuel delievered to the carburetor,

while too high a pressure will cause carburetor flooding.

Check fuel pump as outlined in Section 6M.

Cooling System

The following test may be performed with pressure

testing equipment available commercially for this pur-

pose.
This test provides an excellent means of detecting

internal or external leaks within the cooling system.

1.
Remove radiator cap.

2.
Apply a test pressure of 3 pounds higher than the ra-

diator cap (fig. 18). i.e. 18 pounds for a 15 pound

cap.

3.
If the pressure will not hold, there is either an

internal or external leak in the system.

Cylinder Head Torque and Valve Adjustment

Retorquing the cylinder head bolts is not necessary

unless a gasket has been replaced, or a leak is suspected.

Valve lash must always be adjusted after the head has

been torqued.

Before adjusting the valve lash, it is extremely impor-

tant that the engine be thoroughly warmed up to normal-

ize the expansion of all parts. This is very important

because during the warm-up period, the valve clearances

will change considerably.

Hydraulic

1.
After the engine has been normalized, remove rocker

arm covers and gaskets.

CAUTION: Do not pry rocker arm cover loose.
Gaskets adhering to cylinder head and rocker

arm cover may be sheared by bumping end of

rocker arm cover rearward with palm of hand

or a rubber mallet.

2.
With the engine running at idle, back off valve rocker

arm nut until the valve rocker arm starts to clatter.

3.
Turn rocker arm nut down slowly until the clatter

just stops. This is the zero lash position.

4.
Turn nut down 1/4 additional turn and pause 10 sec-

onds until engine runs smoothly* Repeat additional

1/4 turns, pausing 10 seconds each time, until nut

has been turned down 1 full turn from the zero lash

position.

NOTE: This 1 turn preload adjustment must be

done slowly to allow the lifter to adjust itself to

prevent the possibility of interference, between

the inlet valve head and top of piston, which

might result in internal damage and/or bent push

rods.
Noisy lifters should be replaced.

5.
Repeat Steps 2, 3 and 4 to adjust the rest of the

valves.

6. Clean gasket surfaces on cylinder heads and rocker

arm covers with degreaser then install rocker arm

covers, using new gaskets, and torque bolts to

specifications.

Mechanical

1.
Normalize the engine.

2.
Remove rocker arm covers and gaskets.

CAUTION: Do not pry rocker arm cover loose.

Gaskets adhering to cylinder head and rocker

arm cover may be sheared by bumping end of

rocker arm cover rearward with palm of hand

or a rubber mallet.

3.
Use a socket wrench on self-locking rocker arm stud

nut and adjust as needed to obtain valve lash (see

tune up chart) measured between rocker arm and

valve stem with a leaf type feeler gauge.

4.
Stop engine, clean gasket surfaces on cylinder heads

and rocker arm covers with degreaser then install

rocker arm covers, using new gaskets, and torque

bolts to specifications.

Fig.
19
- Oil Deflector Clips Installed

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE
6-12

ENGINE
MECHANICAL

IN LINE

INDEX

Page

General Description . „ 6-12

Component Replacement and Adjustment 6-12

.Engine Assembly 6-12

Removal 6-12

Installation 6-13

Manifold Assembly 6-14

Removal . 6-14

Installation 6-14

Rocker Arm Cover . 6-14

Removal 6-14

mstallation . . . 6-14

Valve Mechanism
......
1 6-14

Removal 6-14

Installation and Adjustment . 6-14

Valve Lifters
..............
6-15

Locating Noisy Lifters
„.;....
6-15

Removal
.'.*...•
6-15

Installation . 6-15

Valve Stem Oil Seal and/or Valve Spring . 6-16

Replacement . 6-16

Cylinder Head Assembly . 6-16

Removal 6-16

Installation . 6-16

Oil Pan . » 6-17

Removal . . . ; . . 6-17

Installation
.........
. 6-17

Oil Pump . 6-18
Page

Removal . 6-18

Installation . 6-18

Oil Seal (Rear Main) . 6-19

Replacement 6-19

Crankshaft Pulley and Hub 6-19

Removal 6-19

Installation 6-19

Torsional Damper 6-19

Removal 6-19

Installation 6-19

Crankcase Front Cover . 6-20

Removal . 6-20

Installation 6-20

•
Oil Seal (Front Cover) 6-20

Replacement 6-20

Camshaft 6-21

Measuring Lobe Lift . ... .
.-.••.-.
6-21

Removal 6-21

Installation 6-22

Timing Gears
..••••.............••• 6—22

Replacement
6-22

Flywheel
6-22

Removal
* 6-22

Installation
6-22

Engine
Mounts
6-23

Replacement
(Front)
6-23

Replacement
(Rear)
. 6-23

GENERAL DESCRIPTION

The
In
Line engines
(fig. 1L)
covered
in
this section

are
the 1H3 cu. in. L4, the 194,
230
and
250
cu. in. L6,

regardless
of
which passenger vehicle they
are
used
in.

This section covers
the
removal
and
installation
of en-

gine assemblies;
the
removal, installation
and
adjustment

of some sub-assemblies
and
replacement
of
some
com-

ponents.
For
service
to all
components
and
sub-assem-

blies (after removal)
and
removal
of
some sub-assem-

blies,
refer
to
Section
6 of the
Chassis Overhaul Manual.
Because
of the
interchangeability
and
similarity
of

many engine sub-assemblies
and
engine parts, regardless

of which passenger vehicle they
are
used
in,
typical illus-

trations
and
procedures
are
used except where specific

illustrations
or
procedures
are
necessary
to
clarify
the

operation. Although illustrations showing bench opera-

tions
are
used, most single operations, when
not
part
of a

general overhaul, should
be
performed
(if
practical) with

the engine
in the
vehicle.

COMPONENT REPLACEMENT
AND
ADJUSTMENT

ENGINE ASSEMBLY

Removal

1.
Drain cooling system
and
engine
oil.

2.
Remove
air
cleaner
and
disconnect battery cables
at 7.

battery.

3.
Remove hood
as
outlined
in
Section 11.

4.
Remove radiator
and
radiator shroud
as
outlined
in

Section 13.

5.
Remove
fan
blade
and
pulley
as
outlined
in
Section

6K.

6. Disconnect wires
at:

• Starter Solenoid
8.

• Delcotron
9.
Temperature Switch

Oil Pressure Switch

Coil

Disconnect:

Accelerator linkage
at
manifold bellerank.

Exhaust pipe
at
manifold flange.
.

Fuel line (from tank)
at
fuel pump.

Vacuum line
to
power brake unit
at
manifold
(if

so equipped).

• Power steering pump lines
at
pump
end (if so

equipped).

Raise vehicle
and
place
on
jack stands.

Remove propeller shaft.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-14

b.
Bolt transmission to engine, then raise engine and

transmission assembly and install flywheel to

converter attaching bolts.

c. Install converter
housing*
underpan and starter.

3.
Tilt and lower engine and transmission assembly into

the chassis as a unit, guiding engine to align front

mounts with frame supports.

4.
Install front mount through bolts and torque to

specifications.

5.
Raise engine enough to install rear crossmember,

then install crossmember, install rear mount, lower

engine and torque bolts to specifications.

6. Remove lifting device and lifting adapter then install

rocker arm cover as outlined.

7.
On synchromesh equipped vehicles, install clutch

cross shaft engine bracket, then adjust and connect

clutch as outlined in Section 7.

8. Connect:

• Speedometer cable.

• Shift linkage at transmission.

9; Install propeller shaft.

10.
Remove jack stands and lower vehicle.

11.
Connect:

Power steering pump lines (if disconnected).

Vacuum line to power brake unit (if disconnected).

Fuel line at fuel pump.

Exhaust pipe at manifold flange.

Accelerator linkage at manifold bellcrank.

12.
Connect wires at:

Coil

Oil pressure switch

Temperature switch

Delcotron

Starter solenoid

13.
Install pulley, fan blade and fan belt as outlined in

Section 6K.

14.
Install radiator and shroud as outlined in Section 13.

15.
Install and adjust hood as outlined in Section 11.

16.
Connect battery cables.

17.
Fill with coolant, engine oil and transmission oil,

then start engine and check for leaks.

18.
Perform necessary adjustments and install air

cleaner.

MANIFOLD ASSEMBLY

Removal

1.
Remove air cleaner.

2.
Disconnect both throttle rods at bellcrank and re-

move throttle return spring.

3.
Disconnect fuel and vacuum lines at carburetor.

Disconnect choke cable on \A engines.

4.
Disconnect crankcase ventilation hose at rocker arm

cover.

5.
Disconnect exhaust pipe at manifold flange and dis-

card packing.

6. Remove manifold attaching bolts and clamps then

remove manifold assembly and discard gaskets.

7.
Check for cracks in manifold castings.

8. If necessary to replace either intake or exhaust

manifolds, separate them by removing one bolt and

two nuts at center of assembly. Reassemble mani-

folds using a new gasket. Tighten finger tight and

torque to specifications after assembly to cylinder

head. Transfer all necessary parts.
Installation

1.
Clean gasket surfaces on cylinder head and

manifolds*

2.
Position new gasket over manifold end studs on head

and carefully install the manifold in position making

sure the gaskets are in place.

3.
Install bolts and clamps while holding manifold in

place with hand.

4.
Torque bolts to specifications.

NOTE: On L6 engines center bolt and end bolt

torque differ.

5.
Connect exhaust pipe to manifold using a new

packing.

6. Connect crankcase ventilation hose at rocker arm

cover.

7.
Connect fuel and vacuum lines at carburetor.

8. On L4 engines connect choke cable and adjust as out-

lines in Section 6M.

9. Connect throttle rods at bellcrank and install throttle

return spring.

10.
Install air cleaner, start engine, check for leaks and

adjust carburetor idle speed and mixture.

ROCKER ARM COVER

Removal

1.
Disconnect crankcase ventilation hose(s) at rocker

arm cover.

2.
Remove air cleaner.

3.
Disconnect temperature wire from rocker arm cover

clips.

4.
Remove rocker arm cover. '

CAUTION: Do Not pry rocker arm cover loose

Gaskets adhering to cylinder head and rocker

arm cover may be sheared by bumping end of

rocker arm cover rearward with palm of hand or

a rubber mallet.

Installation

1.
Clean gasket surfaces on cylinder head and rocker

arm cover with degreaser then, using anew gasket,

install rocker arm cover and torque bolts to

specifications.

2.
Connect temperature wire at rocker arm cover clips.

3.
Install air cleaner.

4.
Connect crankcase ventilation hoses.

VALVE MECHANISM

Removal

1.
Remove rocker arm cover as outlined.

2.
Remove rocker arm nuts, rocker arm
balls,
rocker

arms and push rods.

NOTE:
Place rocker arms, rocker arm balls

and push rods in a rack so they may be rein-

stalled in the same location.

Installation and Adjustment

NOTE:
Whenever new rocker arms and/or

rocker arm balls are being installed, coat bear-

ing surfaces of rocker arms and rocker arm

balls with Molykote or its equivalent.

1.
Install push rods,

socket.
Be sure push rods seat in lifter

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-25

refer to Section 6 of the Chassis Overhaul Manual.

Because of the interchangeability and similarity of

many engines, engine sub-assemblies and engine parts,

regardless of which passenger vehicle they are used in,

typical illustrations and procedures are used except
where specific illustrations or procedures are necessary

to clarify the operation. Although illustrations showing

bench operations are used, most single operations, when

not part of a general overhaul, should be performed (if

practical) with the engine in the vehicle.

COMPONENT REPLACEMENT AND ADJUSTMENT

ENGINE ASSEMBLY

Removal

• .1. Drain cooling system and engine oil.

2.
Remove air cleaner and disconnect battery cables at

battery.

3.
Remove hood as outlined in Section 11.

4.
Remove radiator and shroud as outlined in Sec-

tion 13.

5. Remove fan blade and pulley as outlined in Sec-

tion 6K.

6. Disconnect wires at:

• Starter solenoid

• Delcotron

• Temperature switch

• Oil pressure switch

• Coil

7. Disconnect:

• Accelerator linkage at pedal lever.

• Exhaust pipes at manifold flanges.

• Vacuum line to power brake unit at manifold (if

so equipped),

• Power steering pump lines at pump end (if so

equipped).

• Fuel line (from tank) at fuel pump.

• Engine cooler lines (if so equipped).

• Oil pressure gauge line (if so equipped).

8. Raise vehicle and place on jack stands.

9. Remove propeller shaft.

NOTE:
If plug for propeller shaft opening

in transmission is not available, drain

transmission.

10.
Disconnect:

• Shift linkage at transmission.

• Speedometer cable at transmission.

• Transmission cooler lines (if so equipped).

11.
On synchromesh equipped vehicles, disconnect clutch

linkage at cross-shaft then remove cross-shaft en-

gine bracket.

12.
Remove rocker arm covers as outlined, then attach

engine lifting adapter at the proper cylinder head bolt

locations.

13.
Remove front mount bolts.

14.
Attach lifting device and raise engine to take weight

off front mounts, then remove rear mount bolts.

15.
Raise engine to take weight off rear mount, then re-

move crossmember.

NOTE:
On Chevrolets it will be necessary to

remove mount from transmission before cross-

member can be removed.

16.
Remove engine-transmission assembly from vehicle

as a unit.

17.
Remove transmission (and clutch):
Synchromesh Transmission

a. Remove clutch housing cover plate screws.

b.
Remove bolts attaching the clutch housing to en-

gine block then remove transmission and clutch

housing as a unit.

NOTE:
Support the transmission as the last

mounting bolt is removed, and as it is being

pulled away from the engine (to prevent damage

to clutch disc).

c. Remove starter and clutch housing rear cover

plate.

d. Loosen clutch mounting bolts a turn at a time (to

prevent distortion of clutch cover) until the spring

pressure is released. Remove all bolts, clutch

disc and pressure plate assembly.

Automatic
Transmission

a. Lower engine, secured by the hoist, and support

engine on blocks.

b.
Remove starter and converter housing underpan.

c. Remove flywheel-to-converter attaching bolts.

d. Support transmission on blocks.

e. Remove transmission-to-engine mounting bolts.

f. With the hoist attached, remove blocks from the

engine only and slowly guide the engine from the

transmission.

18.
Mount engine in stand.

Installation

1.
Attach lifting device to engine and remove engine

from engine stand.

2.
Install transmission (and clutch):

Synchromesh Transmission

a. Install the clutch on flywheel as outlined in Sec-

tion 7.

b.
Install clutch housing rear cover and starter.

c. Install transmission and clutch housing as out-

lined in Section 7.

d. Install clutch housing cover screws and tighten

securely.

Automatic
Transmissions

a. Position engine adjacent to the transmission and

align the converter with the flywheel.

b.
Bolt transmission to engine, then raise engine and

transmission assembly and install flywheel to

converter attaching bolts.

c. Install converter housing underpan and starter.

3.
Tilt and lower engine and transmission assembly into

the chassis as a unit, guiding engine to align front

mounts with frame supports.

4.
Install front mount bolts and torque to specifications.

5. Raise engine enough to install rear crossmember,

then install crossmember, install rear mount, lower

engine and torque rear mount to specifications.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-26

6. Remove lifting device and lifting adapter then install

rocker arm covers as outlined.

7.
On synchromesh equipped vehicles, install clutch

cross-shaft engine bracket, then adjust and connect

clutch as outlined in Section 7.

8. Connect:

• Speedometer cable.

• Shift linkage at transmission.

• Transmission cooler lines (if so equipped).

9. Install propeller shaft.

10.
Remove jack stands and lower vehicle.

11.
Connect: \ '

Power steering pump lines (if so equipped).

Vacuum line to power brake unit (if so equipped).

Exhaust pipes at manifold flanges.

Accelerator linkage at pedal lever.

Fuel line at fuel pump.

Engine cooler lines (if so equipped).

Oil pressure gauge lines (if so equipped).

12.
Connect wires at:

Coil

Oil pressure switch

Temperature switch

Delcotron

Starter solenoid

13.
Install pulley, fan blade and fan belt as outlined in

Section 6K.

14.
Install radiator and shroud as outlined in Section 13.

15.
Install and adjust hood as outlined in Section 11.

16.
Connect battery cables.

17.
Fill with coolant, engine oil and transmission oil,

then start engine and check for leaks.

18.
Perform necessary adjustments and install air

cleaner.

INTAKE MANIFOLD

Removal

1.
Drain radiator and remove air cleaner.

2.
Disconnect:

Battery cables at battery.

Upper radiator and heater hose at manifold.

Accelerator linkage at pedal lever.

Fuel line at carburetor. ;

Wires at temperature sending switch and coil

(both sides).

Power brake hose at carburetor base.

Spark advance hose at distributor.

Crankcase ventilation hoses (as required).

3.
Remove distributor cap and mark rotor position with

chalk. Remove distributor clamp and distributor,

then position distributor cap rearward clear of

manifold.

4.
Remove coil.

5.
Remove manifold-to-head attaching bolts, then re^

move manifold, (with carburetor on) from engine and

discard gaskets and seals.

6. If manifold is to be replaced,,transfer:

Carburetor and carburetor mounting studs.

Temperature sending switch.

Water outlet and thermostat (use new gasket).

Heater hose adapter.

Choke coil.

Installation

1.
Clean gasket and seal surfaces of manifold, cylinder
heads and block.

2.
Install manifold end seals on block as shown (fig.

2V).

3.
Install side gaskets on cylinder heads using sealing

compound around water passages (fig. 2V).

4.
Install manifold bolts, and torque to specifications in

the sequence outlined on the Torque Sequence Chart.

5.
Install coil.

6. Install distributor with the rotor pointing at the chalk

mark, then install distributor cap.

NOTE:
If the crankshaft has been rotated while

the distributor was removed, time distributor to

number 1 cylinder as outlined in Section 6Y.

7.
Connect:

Battery cables at battery.

Upper radiator and heater hose at manifold.

Accelerator linkage at pedal lever.

Fuel line at carburetor.

Wires at temperature sending switch and coil

(both sides)!

Power brake hose at carburetor base.

Spark advance hose at distributor.

Crankcase ventilation hoses (as required).

Fill with coolant, start engine, check for leaks and

adjust timing and carburetor idle speed and mixture.

EXHAUST MANIFOLD

Removal

NOTE:
If equipped with "Air Injection Reactor

System", remove air manifold and tubes as out-

lined in Section 6T.

1.
Disconnect battery ground cable.
-

2.
Disconnect and remove Delcotron (as required).

3.
On 396 and 427 cu. in. engines, remove spark plugs

Fig. 2V - Intake Manifold Gasket and Seal Location

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE FUEL
6M-10

the
two
"FILL71 lines
(fig.
6A). Refill whenever
the
level

falls below the lower
<'FILL"
line.

Storing Tool

When
the
tool
is
not used, fully depress
the
inner tube.

This seals
off
the
oil
reservoir from the vent hole
to pre-

vent
oil
loss
if
the tool
is
tipped.

Fig. 6A-Filling Tool with
Oil

FUEL PUMP

INDEX

Page

General Description
. . . . 6M-10

Service Procedures .6M-10

Inspection .6M-10
Page

Test
. . ; 6M-10

Removal
6M-11

Installation
6M-11

GENERAL DESCRIPTION

The fuel pump
(fig. IP)
used
on all
Chevrolet vehicles

covered
in
this manual
are of the
diaphragm type.
The

pumps
are
actuated
by an
eccentric located on
the
engine

camshaft.
On
in-line engines,
the
eccentric actuates
the

rocker arm*
On V-8
engines,
a
push
rod
(located be-

tween
the
camshaft eccentric and fuel pump) actuates
the

pump rocker
arm.
Because
of
design, this pump
is

serviced
as an
assembly only.

Fig.
IP—Fuel Pump (Non-Serviceable)

SERVICE PROCEDURES

Inspection

The fuel pump should
be
checked
to
make sure
the

mounting bolts
and
inlet and outlet connections
are
tight.

Test

Always test pump while
it is
mounted on the engine
and
be sure there
is
gasoline
in
the tank.

The line from
the
tank
to the
pump
is the
suction side

of
the
system and the line from the pump
to the
carbure-

tor
is the
pressure side
of the
system.
A
leak on
the

pressure side, therefore, would
be
made apparent
by

CHEVROLET CHASSIS SERVICE MANUAL

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