1967 CHEVROLET CAMARO coolant

HEATER AND AIR CONDITIONING 1A-73

Fig.
105—Comfortron Control Head

10.
Introduce R-12 vapor at cylinder (room) temperature

and pressure.

11.
Leak test all fittings and connections and give partic-

ular attention to a leak test at the compressor shaft

seal if compressor has not been leak tested on the

bench.

12.
Complete system processing and charge system.

FUSES

A fuse, located in the junction block protects the entire

air conditioning system except for the blower when op-

erating at high speed.

A second fuse, to protect the high speed blower circuit,

is located in the electrical wiring between the horn relay

and the Air Conditioner relay (except Universal). The
Universal unit has a fuse in the line between the ignition

switch and the Air Conditioner blower switch. See the

specification page for the proper replacement fuse.

FOUR SEASON HEATER COMPONENTS

Corvette

The heater components of the system are, in general,

much the same as those of the standard Corvette heater.

Heater hoses carry the engine coolant to the heater core,

located in the air distributor duct beneath the instrument

panel.

A significant difference is that in the Corvette Air

Conditioning System there is no flow through the heater

core until the COOL IN-HOT PULL knob is pulled out.

This movement opens the vacuum switch on the air

distributor assembly and allows vacuum to be applied

to the water valve mounted in the engine compartment,

opening the valve. Thus the heater core is unheated

until needed, at which time it receives full flow of the

engine coolant. Air passing through the core receives

maximum heat which is tempered by mixing with un-

heated air before entering the passenger compartment.

Heater Core

Replacement

The heater core in the Corvette Air Conditioning

System is removed in the same manner as the core in

the Corvette heater. The distributor assembly must first

be removed from under the dash as covered previously

in this section before the core can be removed and

replaced.

Water Valve

Installation of the water valve is illustrated in Figure

113.
An inoperative valve must be replaced.

Chevrolet

Heater Core

Removal

1.
Disconnect battery ground cable.

2.
Drain radiator

3.
Remove right front fender and skirt assembly.

Fig.
106—Comfortron Temperature Dial Adjustment
Fig.
107—Amplifier Removal

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-2

remotely 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.
Crank engine through at least four compression

strokes to obtain highest possible reading.

4.
Check and record compression of each cylinder.

5.
If one or more cylinders read low tor uneven, inject

about a tablespoon of engine oil on top of pistons

in low reading cylinders (through spark plug

port).
Crank engine several times and recheck

compression.

• If compression comes up but does not necessarily

reach normal, rings are worn.

• If compression does not improve, valves are

burnt, sticking or not seating properly.

• If two adjacent cylinders indicate low compres-

sion and injecting oil does not increase compres-

sion, the cause may be a head gasket leak between

the cylinders. Engine coolant and/or oil in cylin-

ders could result from this defect.

NOTE: If a weak cylinder cannot be located

with the compression check, see "Cylinder Bal-

ance Test" under "Additional Checks and Adjust-

ments" in this section.

Service and Install Spark Plugs (Fig. 2)

1.
Inspect each plug individually for badly worn elec-

trodes,
glazed, broken or blistered porcelains and

replace plugs where necessary. Refer to spark plug

diagnosis information presented in Section 6Y for an

analysis of plug conditions.

2.
Clean serviceable spark plugs thoroughly, using an

abrasive-type cleaner such as sand blast. File the

center electrode flat.

3.
Inspect each spark plug for make and heat range. All

plugs must be of the same make and number.

4.
Adjust spark plug gaps to specifications using a

round feeler gauge.
PORCELAIN

INSULATOR

INSULATOR CRACKS

OFTEN OCCUR HERE

CENTER ELECTRODE

[FILE FLAT WHEN

ADJUSTING GAP-

[DO NOT BEND!
(PROPER GAP)

(BEND TO ADJUST GAP)

CAUTION:

adjust gap.
Fig.
2 - Spark Plug Detail

Never bend the center electrode to

Always adjust by bending ground or

side electrode.

If available, test plugs with a spark plug tester.

Inspect spark plug hole threads and clean before in-

stalling plugs. Corrosion deposits can be removed

with a 14 mm. x 1.25 SAE spark plug tap (available

through local jobbers) or by using a small wire brush

in an electric drill. (Use grease on tap to catch

chips.)

ADJUST DWELL

ANGLE SETTING OR

POINT OPENING

Fig.
1 - Checking Compression
Fig.
3 - Distributor (In Line)

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 6-14

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 6-18

NOTE:
Bolts into crankcase cover should be

installed last. They are installed at an angle

and holes line up after rest of pan bolts are

snugged up.

Chevrolet and Camaro

a. If crankshaft was rotated while pan was off, place

timing mark at 6:00 o'clock position.

b.
Install oil pan and torque bolts to specifications.

c. Using a suitable jack (and a block of wood to prevent

damaging oil pan) raise engine enough to remove 2" x

4"
wood blocks, then lower engine.

d. On vehicles equipped with automatic transmission

install converter housing underpan, then connect

transmission cooler lines.

e. Install and connect starter.

f. Lower vehicle and install fan blades as outlined in

Section 6K.

g. Connect upper and lower radiator hoses.

h. Install through bolts in engine front mounts.

i. Connect battery positive cable.

j.
Fill radiator with coolant and fill engine with oil,

then start engine and check for leaks.

Chevelie

* a. Install oil pan and torque bolts to specifications.

b.
On vehicles equipped with automatic transmission,

install converter housing underpan.

c. Install starter.

d. Install engine as outlined.

Chevy II

a. Install oil pan and torque bolts to specifications.

Fig.
7L- Removing Oil Sea! (Lower Half)
Fig.
8L - Removing Oil Seal (Upper Half)

b.
On L6 engines, install front crossmember.

c. Connect steering idler arm.

d. Install starter and connect wires.

e. Connect battery cable, fill with oil, start engine and

check for leaks.

OIL PUMP

Removal

1.
Remove oil pan as outlined.

2.
Remove two flange mounting bolts, pickup pipe bolt,

then remove pump and screen as an assembly.

Installation

1.
Align oil pump drive shafts to match with distributor

tang, then install oil pump to block positioning flange

over distributor lower bushing. Use no gasket.

NOTE:
Oil pump should slide easily into place,

if not, remove and reposition slot to align with

distributor tang.

2.
Install oil pan using new gaskets and seals as

outlined.

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 6-31

Chevy II

1.
Disconnect battery positive cable.

2.
Drain engine oil.

3.
Disconnect and remove starter.

4 Disconnect steering idler arm bracket at right hand

frame rail and swing steering linkage down for pan

clearance.

5.
Disconnect* exhaust pipes at manifolds and allow

pipes to hang free.

6. Remove oil pan and discard gaskets and seals.

Corvette

1.
Disconnect battery positive cable then remove oil

dipstick and tube.

2.
Raise and support vehicle then drain engine oil.

3.
Remove starter and flywheel underpan.

4.
Disconnect steering linkage idler at frame and lower

the linkage.

5.
Remove oil pan and discard gaskets and seals.

6. On Hi-Performance engines, the oil baffle must

be removed before additional operations can be

performed.

NOTE: On the 427 cu. in. engine, the oil pan

has three 1/4" x 20 attaching bolts at crankcase

front cqver. One located at each corner and one

at lower center.

Installation

1.
Thoroughly clean all gasket sealing surfaces.

NOTE: Use a new pan. gasket set.

2.
Install side gaskets on pan rails, using.gasket sealer

as a retainer.

3.
Install rear oil pan seal in groove in rear main

bearing cap with ends (fig. 9V) butting side gaskets.

4.
Install oil pan front seal in groove in .crankcaee front

cover, with ends butting side gaskets.

5.
If crankshaft was rotated while £>an was off, place

timing mark at 6:00 o'clock position.

6. Install oil pan and torque bolts to specifications.

NOTE: On 396 and 427 cu. in. engines, start

three 1/4" x 20 bolts into crankcase front cover

before tightening, any other pan bolts.

7.
Complete installation as follows:

Chevrolet
and Camaro

a. Using a suitable jack (and a block of wood to pre-

vent damaging oil pan) raise engine enough to re-

move 2" x 4" wood blocks, then lower engine.

b.
On vehicles equipped with automatic transmission

install converter housing underpan.

c. Install through bolts in engine front mounts.

d. Install and connect starter. Connect steering rod

at idler lever.

e. Lower vehicle and install fan blade.

f. Cbnnnect lower radiator hose, then install oil dip

stick tube and dip stick.

g. Connect distributor cap and battery positive

cable.

h. Fill radiator with coolant and fill engine with oil,

then start engine and check for leaks.

Chevelle

a. On vehicles equipped with automatic transmission
Fig.
9V - Oil Pan Gasket and Seal Location

install converter housing underpan.

b.
.Install starter.

c. Install, engine as outlined.

Chevy II

a. Connect exhaust pipe to manifold flange using new

packing seals.

b.
Connect steering idler arm bracket.

c. Connect starter wires..

d. Connect battery cable.

e. Fill with oil, start engine and check for leaks.

Corvette

a. Connect steering linkage.

b.
Install oil dip stick tube and dip stick then con-

nect battery cables.

c. Fill engine with oil, then start engine and check

for leaks.

OIL PUMP

Removal

1.
Remove oil pan as outlined.

2.
Remove pump to rear main bearing cap bolt and re-

move pump and extension shaft.

Installation

1.
Assemble pump and extension shaft to rear main

CHEVROLET CHASSIS SERVICE MANUAL

SECTION 6K

ENGINE COOLING

INDEX

Page

General Description . . . 6K-1

Maintenance and Adjustments 6K-1

Coolant Level 6K-1

Coolant System Checks 6K-1

Periodic Maintenance 6K-2

Cleaning 6K-2

Reverse Flushing 6K-2

Radiator 6K-2
Page

Cylinder Block and Cylinder Head 6K-2

Hot Water Heater 6K-2

Fan Belt . 6K-2

Adjustment ....". 6K-2

Thermostat . 6K-2

Replacement 6K-2

Water Pump. . . . 6K-3

Removal 6K-3

Installation 6K-3

GENERAL DESCRIPTION

A pressure cooling system is provided for on all

models by a pressure type radiator cap (fig. 1). The

pressure type radiator cap used is designed to hold a

pressure above atmospheric pressure in the cooling

system. Excessive pressure is relieved by a valve within

the cap that opens to radiator overflow.

The water pump is a ball bearing, centrifugal vane

impeller type. It requires no care other than to make

certain the air vent at the top of the housing and the drain

holes in the bottom do not become plugged with dirt or

grease. Removal and installation of the water pump is

covered in this section. For overhaul procedures of the

water pump refer to Section 6K of the Passenger Chassis

Overhaul Manual.
For radiator, refer to Section 13 of this manual For

radiator shroud, refer to Section 11 of this manual.

Fig.
I—Pressure Radiator Cap

MAINTENANCE AND ADJUSTMENTS

Coolant Level

The radiator coolant level should only be checked when

the engine is cool, particularly on cars equipped with air

conditioning. If the radiator cap is removed from a hot

cooling system, serious personal injury may result

The cooling system fluid level should be maintained

one inch below the bottom of the filler neck of the radia-

tor when cooling system is cold, or at the bottom of the

filler neck when the system is warm. It is very impor-

tant that the correct fluid level be maintained. The seal-

ing ability of the radiator cap is affected when the cooling

level is too high.

All passenger car cooling systems are pressurized

with a pressure cap which permits safe engine operation

at cooling temperatures of
up
to 247°F.

When the radiator cap is removed or loosened, the

system pressure drops to atmospheric, and the heat

which had caused water temperature to be higher than

212°F, will be dissipated by conversion of water to

steam. Inasmuch as the steam may form in the engine

water passages, it will blow coolant out of the radiator

upper hose and top tank, necessitating coolant replace-

ment Engine operating temperatures higher than the

normal boiling point of water are in no way objectionable

so long as the coolant level is satisfactory when the

engine is cooL

Upon repeated coolant loss, the pressure radiator cap

and seat should be checked for sealing ability. Also, the
cooling system should be checked for loose hose con-

nections, defective hoses, gasket leaks, etc.

Coolant System Checks

1.
Test for restriction in the radiator, by warming the

engine up and then turning the engine off and feeling

the radiator. The radiator should be hot at the top

and warm at the bottom, with an even temperature

rise from bottom to top. Cold spots in the radiator

indicate clogged sections.

2.
Water pump operation may be checked by running the

engine while squeezing the upper radiator hose. A

pressure surge should be felt Check for a plugged

vent-hole in pump.

NOTE:
A defective head gasket may allow ex-

haust gases to leak into the cooling system.

This is particularly damaging to the cooling

system as the gases combine with the water to

form acids which are particularly harmful to

the radiator and engine.

3.
To check for exhaust leaks into the cooling system,

drain the system until the water level stands just

above the top of the cylinder head, then disconnect

the upper radiator hose and remove the thermostat

and fan belt. Start the engine and quickly accelerate

several times. At the same time note any appreci-

able water rise or the appearance of bubbles which

CHEVROLET CHASSIS SERVICE MANUAL