ignition CHEVROLET CAMARO 1967 1.G Chassis User Guide

ENGINE 6-4

• Contact points with an overall gray color and only

slight roughness or pitting need not be replaced.

• Dirty points should be cleaned with a clean point

file.

Use only a few strokes of a clean, fine-cut con-

tact file. The file should not be used on other

metals and should not be allowed to become

greasy or dirty. Never use emery cloth or sand-

paper to clean contact points since particles will

embed and cause arcing and rapid burning of

points. Do not attempt to remove all roughness

nor dress the point surfaces down smooth.

Merely remove scale or dirt.

• Clean cam lobe with cleaning solvent, lubricate

cam lobe with "Delco Remy Cam and Ball Bearing

Lubricant" or its equivalent and rotate cam lubri-

cator wick 1/2 turn.

• Replace points that are burned or badly pitted.

NOTE: Where prematurely burned or badly

pitted points are encountered, the ignition sys-

tem and engine should be checked to determine

the cause of trouble so it can be eliminated.

Unless the condition causing point burning or

pitting is corrected, new points will provide no .

better service than the old points. Refer to

Section 6Y for an analysis of point burning or

pitting.

• Check point alignment (fig. 5) then, adjust distri-

. butor contact point gap to .019" (new points) or

.016"
(used points). Breaker arm rubbing block

must be on high point of lobe during adjustment.

NOTE: If contact points have been in service,

they should be cleaned with a point file before

adjusting with a feeler gauge.

• Check distributor point spring tension (contact
Fig. 8 - Manifold Heat Control Valve (In Line)

point pressure) with a spring gauge hooked to

breaker lever at the contact and pull exerted at 90

degrees to the breaker lever. The points should

be closed (cam follower between lobes) and the

reading taken just as the points separate. Spring

tension should be 19-23 ounces. If not within

limits,
replace.

Excessive point pressure" will cause excessive

wear on the points, cam and rubber block. Weak

point pressure permits bouncing or chattering,

resulting in arcing and burning of the points and

an ignition miss at high speed.

4.
Install rotor and distributor cap. Press all wires

firmly into cap towers.

Fig. 7 - Checking Fan Belt Tension
Fig. 9 - Manifold Heat Control Valve (V8)

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-7

Tune Up should be checked whenever the Air Injection

Reactor 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 car-

buretor and the carburetor air cleaner. Carburetors and

distributors for engines with the Air Injection Reactor

System are designed, particularly, for these engines;

therefore, they must not be interchanged with or replaced

by a carburetor or distributor designed for an engine

without the Air Injection Reactor System.

Choke Adjustment (Fig. 11)

With Remote Choke

1.
Remove air cleaner and check to see that choke

valve and rod move freely.

2.
Disconnect choke r*od at choke lever.

Check choke adjustment as follows:

On all except 275 hp 327 cu. in. engines, hold

choke valve closed and pull rod up against stop. The

top of choke rod end should be 1/2 - 1 rod diameter
4.

5.
above top of hole in choke valve lever.

On 275 hp 327 cu. in. engines, hold choke valve

closed and push rod down against stop on thermostat

bracket. The top of the choke rod should be 1/2 - 1

rod diameter below the top of the hole in the choke

lever.

If necessary, adjust rod length by bending rod at off-

set. (Bend must be such that rod enters choke lever

hole freely and squarely.)

Connect rod at choke lever and install air cleaner.

3.
With Manual
Choke

1.
Remove air cleaner.

2.
Push hand choke knob in to within 1/8" of instrument

panel.

3.
Loosen choke cable at carburetor bracket and adjust

cable through the clip until the choke valve is wide

open.

4.
Tighten cable clamp at carburetor bracket and check

operation of choke valve to ensure full closed and

wide open positions.

INSTRUMENT CHECK-OUT

Instrument Hook Up

Connect vacuum gauge, dwell meter, tachometer and

timing light as recommended by the manufacturer of the

equipment being used.

Check and Adjust Dwell

1.
Start engine then ch^ck ignition dwell.

.2.
If dwell is not within specifications, adjust dwell as

follows:

V8 ENGINES

• With engine running at idle, raise the adjustment

screw window-and insert an Allen wrench in the

socket of the adjusting screw (fig. 12).

• Turn the adjusting screw as required until a dwell

reading of 30° is obtained. A 2° variation is al-

lowable for wear.

• Close access cover fully to prevent the entry of

dirt into the distributor.

NOTE: If a dwell meter is not available, turn
adjusting screw clockwise until engine starts to

misfire, then turn screw one-half turn in the op-

posite direction to complete adjustment.

IN LINE ENGINES

• Remove distributor cap and recheck point setting.

If dwell is still not within specifications check the

distributor as outlined in Section 6Y.

Check Dwell Variation

Slowly accelerate engine to 1500 rpm and note dwell

reading. Return engine to idle and note dwell reading. If

dwell variation exceeds specifications, check for worn

distributor shaft, worn distributor shaft bushing or loose

breaker plate.

WINDOW

"HEX" TYPE

WRENCH

Fig.
12 - Setting Point Dwell (V8)
Fig.
13 - Ignition Timing Marks

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE
6-8

Check
and
Adjust Ignition Timing
(Fig. 13)

1.
Disconnect
the
distributor spark advance hose
and

plug
the
vacuum source opening.

2.
Start engine
and run at
idle speed
(see
tune
up
chart).

3.
Aim
timing light
at
timing
tab.

NOTE:
- The
markings
on the
tabs
are in 2°

increments
(the
greatest number
of
markings
on

the
"A"
side
of the "O"). the "O"
markings
is

TDC
of
#1 cylinder
and all
BTDC settings fall
on

the
"A"
(advance) side
of "O".

4.
Adjust
the
timing
by
loosening
the
distributor clamp

and
,
rotating
the
distributor body
as
required, then

tighten
the
clamp.

5.
Stop engine
and
remove timing light
and
reconnect

the spark advance hose.

Adjust Idle Speed
and
Mixture
(Fig. 14)
(Except when

equipped with
Air
Injection Reactor System)

1.
As a
preliminary adjustment, turn idle mixture

screws lightly
to
seat
and
back
out 2
turns.

CAUTION:
Do not
turn idle mixture screw

tightly against seat
or
damage
may
result.

2.
With engine running
at
operating temperature (choke

wide open) adjust idle speed screw
to
bring idle

speed
to
specified
rpm
(automatic transmission
in
drive, manual transmission
in
neutral).

3.
Adjust idle mixture screw
to
obtain highest steady

idle speed
(1/4
turn
out
from lean roll).

4.
Repeat Steps
2 and 3 as
needed
for
final adjustment.

5.
Shut down
the
engine, remove gauges
and
install
air

cleaner.

Adjust Idle Speed
and
Mixture
(Fig. 14)
(With
Air

Injection Reactor System)

The recommended adjustment procedure
for Air
Injec-

tion Reactor System equipped engines
is as
follows:

1.
As a
preliminary adjustment, turn idle mixture

screws lightly
to
seat
and
than back
out 3
turns.

CAUTION:
Do not
turn idle mixture screw

tightly against seat
or
damage
may
result.

2.
With engine running
at
operating temperature, choke

wide open,
and
parking brake applied, adjust idle

specified idle speed (automatic

"drive"-manual transmission
in
to

in
screw

transmission

"neutral").

;3.
Adjust idle mixture screw (turn
in) to
"lean roll"

position; then turn screw
out 1/4
turn
(1/4
turn rich

from "lean roll").
The
definition
of
"lean roll" point

is
a 20 to 30 rpm
drop
in
engine speed, obtained
by

leaning
the
idle mixture.

4.
Repeat Steps
2 and 3 as
needed
for
final adjustments.

ADDITIONAL CHECKS
AND
ADJUSTMENTS

Testing Crankcase Ventilation Valve
(Fig. 15) 0

1.
Connect tachometer
and
vacuum gauge
as for
idle

speed
and
mixture adjustment.

2.
Set
parking brake, start engine
and
adjust idle speed

and mixture.

3.
Disconnect ventilation hose
at
valve, block opening
of

valve
and
read engine
rpm
change.

4.
A
change
of
less than
50 rpm
indicates
a
plugged

ventilation valve
-
replace
the
valve.

Cylinder Balance Test
(Fig. 16)

It
is
often difficult
to
locate
a
weak cylinder.
A com-

pression test,
for
example, will
not
locate
a
leaky intake

manifold,
a
valve
not
opening properly
due to a
worn

camshaft,
or a
defective spark plug.

With
the
cylinder balance test,
the
power output
of one

cylinder
may be
checked against another, using
a set of

grounding leads. When
the
power output
of
each cylinder

is
not
equal,
the
engine will lose power
and run
roughly.

Perform
a
cylinder balance test
as
follows:

1.
Connect
the
tachometer
and
vacuum gauge.

2.
Start engine
and run at 1500 rpm.

3.
Ground large clip
of
grounding leads
and
connect
in-

dividual leads
to all
spark plugs except
the
pair being

tested.

Divide
the
firing order
in
half
and
arrange
one
half

over
the
other.
The
cylinders
to be
tested together
ap-

pear
one
over
the
other.

L4 Firing Order
V8 Firing Order

1-8-4-3-6-5-7-2

1-6, 8-5, 4-7, 3-2

1-3-4-2
= 1-3

4-2

L6 Firing Order

1-5-3-6-2-4
=
=
1-4. 3-2

1-5-3

6-2-4
1-6, 5-2, 3-4
1-8-4-3

6-5-7-2

4.
Operate engine
on
each pair
of
cylinders
in
turn
and

note engine
rpm and
manifold vacuum
for
each pair.

A variation
of
more than
1
inch
of
vacuum
or 40 rpm

between pairs
of
cylinders being tested indicates that

the cylinders
are off
balance.

Battery

The battery should
be
checked with special testing

equipment
and to the
equipment manufacturers specifica-

tions.
See
Section 6Y
for
complete information
on
battery

tests.

Ignition

The following additional ignition checks
may be
made

with
any of
several pieces
of
equipment available
for un-

covering
the
source
of
engine difficulties.
The
specific

operating instructions
of the
equipment manufacturer

should
be
followed:

Cranking voltage

Ignition switch

Distributor resistance

Secondary resistance

Ignition output
and
secondary leakage

Cranking Voltage
(Fig. 17)

1.
Disconnect coil primary lead
at the
coil negative

terminal
to
prevent engine from firing during

cranking.

2.
Connect voltmeter between primary terminal
of coi|

(resistance wire side)
and
ground.

3.
Operate starting motor.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-10

Fig.
15 - Crank case Ventilation Valve

a. If voltage is 9 volts or more and cranking speed

is satisfactory, the battery, starter, cables,

starter switch and ignition circuit to coil (by-

passing resistance wire) are in good condition.

b.
If below 9 volts, check circuit until difficulty is

located.

Meter reading below specification—Weak bat-

tery; defective cables, connections, switch or

starter; defective ignition circuit to coil.

Cranking speed below normal--Excessive re-

sistance in cables or starting motor; excessive

mechanical drag in engine.

Uneven cranking speed—Uneven compression,

defective starter or starter drive.

Ignition Switch

With voltmeter connected as described for the Cranking

Voltage Test, turn ignition switch to ON. Voltage should

drop to 5 to 7 volts as current is now passing through

high resistance wire connected between ignition switch

and (+) positive terminal of coil. If battery voltage of

12 volts is obtained, the starter solenoid is by-passing

the high resistance wire connected between ignition

switch and (+) positive terminal of coil, thus the starter

solenoid is not functioning properly to bypass the ignition

resistance wire or the ignition circuit is incorrectly

wired.

Distributor Resistance

Use equipment as directed by manufacturer.

Excessive
(t n ti ft

Fig.
16 - Cylinder Balance Test
Fig.
17 - Testing Cranking Voltage

resistance in primary circuit must be eliminated before

continuing with test procedure.

Secondary Resistance

Use equipment as dire6ted by manufacturer.

• Uniform "normal readings" as specified by manu-

facturer indicate all secondary circuit components

are in good condition.

• If all readings are "below normal," check for cor-

roded coil tower terminal, poorly connected or

broken coil wire, center cap electrode or rotor tip

burned, or an open secondary in coil.

• If readings are "higher than normal" at two or more

plugs adjacent in firing order, cross firing is oc-

curring in distributor cap or between spark plug ca-

bles concerned.

• If meter reads off scale to left, the coil polarity is

reversed. Check for reversed coil primary wires,

wrong coil or reversed vehicle battery connections.

Ignition Output and Secondary Leakage

Use equipment as directed by manufacturer.

• GOOD readings indicate both ignition output and

secondary insulation are good.

• If all readings are BAD or if ignition test calibrator

cannot be adjusted to Set Line, check for high re-

sistance in primary circuit, defective distributor

points, coil or condenser.

e If readings are BAD when certain plug wires are

lifted off, check for cracks or carbon tracks in dis-

tributor cap or defective insulation on those plug

wires being lifted off.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-16

5.
Adjust ignition timing and carburetor idle speed and

mixture.

VALVE STEM OIL SEAL AND/OR VALVE SPRING

Replacement

1.
Remove rocker arm cover as outlined.

2.
Remove spark plug, rocker arm and push rod on the

cylinder(s) to be serviced.

3.
Apply compressed air to the spark plug hole to hold

the valves in place.

NOTE: A tool to apply air to the cylinder is

available through local jobbers or may be manu-

factured. In manufacturing this Tool a AC-46N

Spark Plug or its equivalent is recommended.

This will make the Tool universal for all

Chevrolet engines. Chisel the spark plug as

shown, then drive the porcelain out of the plug

by tapping the center electrode against a hard

block. Using a 3/8" pipe tap, cut threads in the

remaining portion of the spark ^>lug and assem-

ble as shown (fig. 3L).

4.
Using Tool J-5892 to compress the valve spring, re-

move the valve locks, valve cap, valve shield and

valve spring and damper (fig. 4L).

5.
Remove the valve stem oil seal.

6. To replace, set the valve spring and damper, valve

shield and valve cap in place. The close coiled end

of the spring is installed against the cylinder head.

Compress the spring with
Too^
J-5892 and install oil

seal in the lower groove of the stem, making sure the

seal'is flat and not twisted.

NOTE: A light coat of oil on the seal will help

prevent twisting.

7.
Install the valve locks and release the compressor

tool, making sure the locks seat properly in the

upper groove of the valve stem.

NOTE: Grease may be used to hold the locks

in place while releasing the compressor tool.

8. Install spark plug, using a new gasket, and torque to

specifications.

9. Install and adjust valve mechanism as outlined.

CYLINDER HEAD ASSEMBLY

Removal

1.
Remove manifold assembly as. outlined.

2.
Remove valve mechanism as outlined.

3.
Drain cooling system (block).

4.
Remove fuel and vacuum line from retaining clip at

water outlet then disconnect wires from temperature

sending units.

5.
Disconnect upper radiator hose at water outlet hous-

ing and battery ground strap at cylinder head.

6. Remove coil (L6 engines only).

7.
Remove cylinder head bolts, cylinder head and gas-

ket. Place cylinder head on two blocks of wood to

prevent damage.

Installation

CAUTION: The gasket surfaces on both the

head and the block must be clean of any foreign
matter and free of nicks or heavy scratches.

Cylinder bolt threads in the block and threads

on the cylinder head bolt must be cleaned. (Dirt

will affect bolt torque.) Do not use gasket sealer

on composition steel asbestos gasket.

Fig. 3L -
AIF
Adapter Tool

1.
Place the gasket in position over the dowel pins with

the bead up.

2.
Carefully guide cylinder head into place over dowel

pins and gasket.

3.
Coat threads of cylinder head bolts with sealing com-

pound and install finger tight.

4.
Tighten cylinder head bolts a little at a time in the

sequence shown on the torque sequence chart until

the specified torque is reached.

5.
Install coil (if removed).

6. Connect upper radiator hose and engine ground strap.

7.
Connect temperature sending unit wires and install

fuel and vacuum lines in clip at water outlet.

8. Fill cooling system.
•

9. Install manifold assembly as outlined.

10.
Install and adjust valve mechanism as outlined.

Fig.
4L
- Compressing Valve Spring

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-21

CAUTION: Support cover
•
at sealing area.

(Tool J-971 may be used as support.)

Without Cover
Removal

1.
With crankshaft pulley and nub or torsional damper

removed, pry old seal out of cover from the front

with a large screw driver, being careful not to dam-

age the seal surface on the cover.

2.
Install new seal so that open end of seal is toward the

inside of cover and drive it into position with Tool

J-8340 (fig. 13L).

CAMSHAFT

Measuring Lobe Lift

NOTE: Procedure is similar to that used for

checking valve timing.. If improper valve

operation is indicated, measure the lift of each

push rod in consecutive order and record the

readings.

1.
Remove valve mechanism as outlined.

2.
Position indicator with ball socket adapter on push

rod (fig. 14L).

3.
Rotate the crankshaft slowly in the direction of rota-

tion until the lifter is on the heel of the cam lobe.

At this point, the push rod will be in its lowest

position.

4.
Set dial indicator on zero, then rotate the crankshaft

slowly, or attach an auxiliary starter switch and

"bump" the engine over, until the push rod is in the

fully raised position.

CAUTION: 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.
Fig.
15L - Timing Gear Marks

5.
Compare the total lift recorded from the dial indica-

tor with specifications.

6. Continue to rotate the crankshaft until the indicator

reads zero. This will be a check on the accuracy of

the original indicator reading.

7.
If camshaft readings for all lobes are within specifi-

cations, remove dial indicator assembly.

8. Install and adjust valve mechanism as outlined.

Removal

1.
Remove valve lifters as outlined,

2.
Remove crankcase front cover as outlined.

3.
Remove radiator as outlined in Section 13.

4.
Remove grille as outlined in Section 13.

5.
Remove fuel pump as outlined in Section 6M.

6. Align timing gear marks then remove the two cam-

shaft thrust plate bolts by working through holes in

Fig.
ML - Measuring Camshaft Lobe Lift
Fig.
16L - Checking Camshaft Gear Runout

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-37

Fig.
27V—Removing Camshaft

4.
Set dial indicator on zero, then rotate the damper

slowly, or attach an auxiliary starter switch and

"bump" the engine over, until the push rod is in the

fully raised position.

CAUTION: 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 dam-

aged grounding circuit in the ignition switch.

5.
Compare the total lift recorded from the dial indica-

tor with specifications.

6. Continue to rotate the crankshaft until the indicator

reads zero. This will be a check on the accuracy of

the original indicator reading.

7.
If camshaft readings for all lobes are within specifi-

cations, remove dial indicator assembly.

8. Install and adjust valve mechanism as outlined.

Removal

1.
Remove valve lifters as outlined.

2.
Remove crankshaft front cover as outlined.

3.
Remove grille as outlined in Section 13.

4.
Remove fuel pump push rod as outlined * in Sec-

tion 6M.

5.
Complete camshaft removal as follows:

CAUTION: All camshaft journals are the same

diameter and care must be used in removing

camshaft to avoid damage to bearings.

Remove camshaft sprocket to camshaft bolts then

remove sprocket and timing chain together. Sprocket

is a light fit on camshaft. If sprocket does not come

off easily a light blow on the lower edge of the

sprocket (with a plastic mallet) should dislodge the

sprocket.

Install two 5/16" - 18 x 4" bolts in camshaft bolt

holes then remove camshaft (fig. 27V).

Installation

NOTE: Whenever a new camshaft is installed
CONVERTER

BOLT AREA -

DEPRESSED

SYNCHROMESH
RING

GEAR

TRANS.,

AUTOMATIC

Fig.
28V - Flywheel Installation (Typical)

coat camshaft lobes with Molykote or its

equivalent.

1.
Lubricate camshaft journals with engine oil and in-

stall camshaft.

2.
Install timing chain on camshaft sprocket. Hold the

sprocket vertical with the chain hanging down, and

orient to align marks on camshaft and crankshaft

sprockets. Refer to Figure 20V.

3.
Align dowel in camshaft with dowel in hole in cam-

shaft sprocket then install sprocket on camshaft.

Refer to Figure 25V.

4.
Draw the camshaft sprocket onto camshaft using the

mounting bolts. Torque to specifications.

5.
Lubricate timing chain with engine oil.

6. Install fuel pump push rod as outlined in Section 6M.

7.
Install grille as outlined in Section 13.

8. Install crankcase front cover as outlined.

9. Install valve lifters as outlined.

FLYWHEEL

Removal

With transmission and/or clutch housing and clutch

removed from engine, remove the flywheel.

Installation

1.
Clean the mating surfaces of flywheel and crankshaft

to make certain there are no burrs.

2.
Install flywheel on crankshaft and position to align

dowel hole of crankshaft flange and flywheel (fig.

28V).

NOTE: On Automatic Transmission equipped

engines, the flywheel must be installed with the

flange collar to transmission side (fig. 33V).

ENGINE MOUNTS

Engine mounts (fig. 34V) are the nonr adjustable type

and seldom require service. Broken or deteriorated

mounts should be replaced immediately, because of the

added strain placed on other mounts and drive line

components.

Front Mount Replacement

1.
Remove nut, washer and engine mount through-bolt.

2.
Raise engine to release weight from mount.

3.
Remove mount from engine.

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

ENGINE-ELECTRICAL 6Y-7

CHARGING SYSTEM

INDEX

Page

General Description . 6Y-7

Maintenance and Adjustments 6Y-9

Static Checks . 6Y-10

System Condition Check and Voltage

•Regular Adjustment. 6Y-10

General Output 6Y-11

Generator Diode and Field Test 6Y-12

Indicator Lamp-Initial Field Excitation

Circuit Tests . 6Y-12
Page

Field Circuit Resistance Wire Tests 6Y-13

Field Relay Test and Adjustment 6Y-14

Other Harness Checks 6Y-14

Service Operations 6Y-14

Generator 6Y-14

Removal and Installation 6Y-14

Pulley Replacement. 6Y-14

Brush Replacement (6" Delcotron). 6Y-15

Double Contact Regulator . . . . . . 6Y-16

GENERAL DESCRIPTION

The charging system includes the battery, generator,

regulator, telltale light, and necessary wiring to connect

these components. The Delcotron is offered as standard

equipment, although there are various capacities avail-

able on all models.

The Delcotron continuous output A.C. generator (fig.

lc) consists of two major parts, a stator and a rotor. The

stator is composed of a large number of windings as-

sembled on the inside of a laminated core that is attached

to the generator frame. The rotor revolves within the

stator on bearings located in each end frame. Two

brushes are required to carry current through the two

slip rings to the field coils wound concentric with the

shaft of the rotor. Six rectifier diodes are mounted in the

slip ring end frame and are joined to the stator windings

at three internally located terminals.

Diodes are mounted in heat sinks to provide adequate

heat dissipation. The six diodes replace the separately
mounted rectifier as used in other types of application.

The diodes change the Delcotron A.C. current to D.C.

current.

Two regulators (fig. 2c) are available on the 1967 vehi-

cles,
a double contact two unit type and a transistor

regulator. The function of these regulators in the charg-

ing system is to limit the generator voltage to a pre-set

value by controlling the generator field current. Both

regulators have an internal field relay unit. The relay

unit allows the telltale lamp to light (as a bulb check)

with the ignition key on and engine not running. When the

engine is started and the generator begins to charge, the

indicator light goes out indicating that the system is op-

erating normally.

The double contact regulator, when used with the

special 63 amp air conditioning model generator (4 ohm

field coil) uses a field discharge diode internally in the

field circuit (figs. 3c and 4c). The added diode adapts the

BRUSH AND

TERMINAL

ASSEMBLY

SLIP RINGS
SLIP RING

END FRAME

_\

THRU

BOLT
DRIVE END

FRAME

BEARING

BEARING

DIODES

ROTOR

5.5" SERIES ID DELCOTRON
STATOR

ASSEMBLY
GREASE

RESERVOIR

BRUSH

FAN ASSEMBLY

6.2" SERIES 2D TYPE 150 DELCOTRON

Fig.
lc—Delcotron Cross-section View

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-9

63 AMP 1

MODELS ONLY'
BATTERY FUSIBLE

LINK
HORN

FUSIBLE LINK'
TRANSISTOR
FUSIBLE LINK'

Fig.
4c— Circuitry - Voltage Regulator Assemblies (Corvette)

Engine compartment wiring harness incorporates sev-

eral fusible links. Each link is identified with its gage

size. A fusible link is a length of special wire (normally

four wire gages smaller than the circuit it is protecting)

used in wiring circuits that are not normally fused, such

as the ignition circuit. The same size wire with a hypalon

insulation must be used when replacing a fusible link.

The links are:

1.
The pigtail lead at the battery positive cable (except

Corvette) is a 14 gage, brown fusible link protecting

the 10 gage battery charging circuit. This wire is an

integral part of the battery cable assembly and serv-

icing requires replacing the complete battery cable

assembly. On Corvette models this link is installed

as a molded splice at the solenoid "Bat" terminal

and servicing requires splicing in a new link.

2.
A 16 gage black fusible link is located at the horn
4.
relay to protect all unfused wiring of 12 gage or

larger. It is installed as a molded splice and serv-

icing requires splicing in a new link.

The generator warning light and field circuitry (16

gage wire) is protected by a fusible link (20 gage

orange wire) used in the "battery feed to voltage

regulator #3 terminal" wire. The link is installed as

a molded splice in the generator and forward lamp

harness and is serviced by splicing in a new 20 gage

wire as required.

The ammeter circuit on all models is protected by

two orange, 20 gage wire fusible links installed as

molded splices in the circuit at the junction block or

the solenoid "Bat" terminal (Corvette only) and at

the horn relay. Each link is serviced by splicing in a

new 20 gage wire as required.

MAINTENANCE AND ADJUSTMENTS

At regular intervals, inspect the terminals for cor-

rosion an4 loose connections, and the wiring for frayed

insulation. Check mounting bolts for tightness. Check the

drive belt for alignment, proper tension and wear. Be-

cause of the higher inertia and load capacity of the rotor

used in A.C. generators, PROPER BELT TENSION is

more critical than on D.C. generators.

Since the Delcotron and its companion regulator are

designed for use on negative polarity systems only, the

following precautions must be observed. Failure to ob-

serve these precautions may result in serious damage to

the charging system.

1.
When installing a battery, always make absolutely

sure the ground polarity of the battery, generator and

regulator is the same.

2.
When connecting a booster battery, make certain to

connect the correct battery terminals together.

3.
When connecting a charger to the battery, connect the

correct charger leads to the battery
%
terminals.

4.
Never operate the generator on an uncontrolled open
TO SOLENOID

BAT ACC RES. WIRE

Fig.
5c—Typical Wiring Diagram Showing Lead Connections

CHEVROLET CHASSIS SERVICE MANUAL