relay CHEVROLET CAMARO 1967 1.G Chassis Owner's Manual

ENGINE-ELECTRICAL 6Y-8

1

FIELD RELAY^I^p2

"LATCH"
^PFN?^

"P1
TERMINAL
JyJvJCTl^

NO. 2 TERMINAD^5^^^«

NO.
3 TERMINAL ^S5«£

NO.
4 TERMINAL ^^^
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# / VOLTAGE

¥ REGULATOR

1
ACCESS PLUG TO

VOLTAGE ADJUSTMENT

No 4 TERMINAL

Double Contact

Fig.
2c—Voltage Regulator Assemblies
Transistor

regulator to handle the higher field current and enables it

to absorb the increased inductive voltages of the field

coil with satisfactory contact point life.

The double-contact regulator assembly (fig. 2c) con-

sists of a double contact voltage regulator unit and a field

relay unit. This unit uses two sets of contact points on

the voltage regulator unit to obtain desired field excita-

tion under variable conditions. Internal circuit wiring

diagrams of the double contact regulator are shown in

Figures 3c and 4c.

The transistor regulator (fig. 2c) is an assembly com-

posed principally of transistors, diodes, resistors, a

capacitor, and a thermistor to form a completely static

voltage regulating unit in combination with a conventional

vibrating type field relay.

The transistor is an electrical device which limits the
generator voltage to a preset value by controlling the

generator field current. The diodes, capacitor and re-

sistors act together to aid the transistors in controlling

the generator voltage. This is the only function that the

regulator performs in the charging circuit. The

thermistor provides a temperature-compensated voltage

setting. Wiring diagrams of the transistor regulator are

shown in Figures 3c and 4c.

The voltage at which the generator operates is deter-

mined by the regulator adjustment. The regulator voltage

setting can be adjusted externally by removing a pipe plug

in the cover (fig. 2c) and turning the adjusting arm inside

the regulator. This procedure is explained in the followr

ing section, and permits regulator adjustments without

removing the cover.

FUSIBLE

DOUBLE CONTACT
FUSIBLE LINK-^
JUNCTION HORN

BLOCK RELAY

RESISTOR

Q FIELD Q>

DELCOTRON TR-

TRANSISTOR
FUSIBLE LINK-

Fig.
3c-Circuity - Voltage Regulator Assemblies (Except Corvette)

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

ENGINE-ELECTRICAL 6Y-10

circuit. Make absolutely certain all connections in

the circuit are secure.

5.
Do not short across or ground any of the terminals

on the generator or regulator.

6. Do not attempt to polarize the generator.

7.
Do not disconnect lead at generator without first dis-

connecting battery ground cable.

Trouble in the A.C. charging system will usually be

indicated by one or more of the following conditions:

1.
Faulty indicator lamp or ammeter operation.

2.
An undercharged battery (usually evidenced by slow

cranking speeds).

3.
An overcharged battery (usually evidenced by exces-

sive battery water usage).

4.
Excessive generator noise or vibration.

Described below are a series of on-the-vehicle quick

checks which are designed to assist the service tech-

nician in locating troubles within the various components

of the engine electrical system. Additional checks, ad-

justments and overhaul procedures of these components

are also described in the "Charging Systems—Service

Operations Section" and should be referred to as

necessary.

STATIC CHECKS

Before making any electrical checks, perform the fol-

lowing static checks:

1.
Check for loose fan belt.

2.
Check for defective battery. (Refer to Battery).

3.
Inspect all connections, including the slip-on con-

nectors at the regulator and Delcotron.

NOTE: Do not short field to ground to check if

generator is charging since this will seriously

damage the charging system.

SYSTEM CONDITION TEST

This test is used .to indicate the overall condition of the

charging system (both good and defective) and to isolate

the malfunctioning unit if the system is defective.

NOTE: On Corvette models difficulty may be

encountered -when attempting to make the re-
quired test connections at the voltage regulator.

It is advisable to remove the regulator from its

mounting location to perform the necessary con-

nections at the regulator for the following tests

but make sure unit is grounded.

1.
With ignition off, perform the prescribed Static

Checks outlined in this section. Then set hand brake

and shift transmission
into
neutral.

2.
Connect a voltmeter from junction block relay to

ground at regulator base.

CAUTION: Be sure meter clip does not touch a

resistor or terminal extension under regulator,

3.
Connect a tachometer on engine.

4.
Models equipped with Indicator Lamp: Turn ignition

switch on "ON" position and check indicator lamp.

If lamp fails to glow, perform appropriate tests and

corrections (Indicator Lamp Circuit Tests) before

continuing.

Models equipped with Ammeter: Turn ignition

switch to "ACC" with an accessory on and check

ammeter. If ammeter fails to read discharge, check

ammeter circuit before continuing.

5.
Models equipped with Indicator Lamp: If lamp glows,

start the engine and run' it at 1500 rpm or above.

Check indicator lamp. If lamp fails to go out, per-

form appropriate test and corrections (Indicator

Lamp Circuit Test) before continuing.

Models equipped with Ammeter: If ammeter reads

discharge, start the engine and observe ammeter. If

meter fails to move toward charge (from original

position), perform appropriate test and corrections

(Field Circuit Tests) before continuing.

NOTE: At this point a field circuit has been

established and any other problem will lie in

generator or regulator.

6. Turn on high-beam headlights and heater blower

motor to high speed, run engine at or above 1500

rpm (for a few minutes, if necessary) and read the

voltage on meter.

AIR GAP

ADJUSTING NUT

ONLY

ADJUSTING SCREW

(Turn To Adjust

Voltage Setting)

Fig.
6c—Adjusting Voltage Setting

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-11

I
BAT
JUNCTION BLOCK
DELCOTRON

—GRQ

BATTERY

&HJVVWV

0 VA OHM TEST RELAY >

RESISTOR [ 1 d

FUSIBLE

LINK

TO CRANKING

MOTOR
Ik

REGULATOR

VOLTMETER

FUSIBLE LINK

IGN.
SWITCH

Fig.
7c—Voltage Setting Test Connections

NOTE:
Voltage will not greatly exceed 12-1/2

volts until the battery develops a surface charge,

a few minutes generally, unless the battery is

severely discharged or is hot.

If reading is:

a. 12-1/2 volts or more, turn off electrical loads,

stop engine and proceed to Step 7.

b.
Less than 12-1/2 volts, perform "Delcotron Out-

put Test-Voltmeter Method."

(1) Delcotron tests bad—refer to "Service Op-

erations" and repair Delcotron, then repeat

Step 6.

(2) Delcotron tests good—disconnect regulator

connector, remove regulator cover and recon-

nect the connector. Then repeat Step 6 and

turn voltage adjusting screw (fig. 6c) to raise

setting to 12-1/2 volts. On transistor regula-

tor remove pipe plug (fig. 6c), insert screw

driver into slot and turn clockwise one or two

notches to increase setting. Turning counter-

clockwise decreases setting. For each notch

moved, the voltage setting will change ap-

proximately .3 volt. Turn off loads, stop en-

gine and proceed to Step 7. If 12-1/2 volts

cannot be obtained, install a new regulator and

repeat Step 6.

ADJUSTING REGULATOR VOLTAGE

7. Connect a 1/4 ohm-25 watt fixed resistor (purchased

commercially) into the charging circuit at the junc-

tion block as shown in Figure 7c.

NOTE:
Between both leads and the terminal.

8. Run engine at 1500 rpm or above for at least 15

minutes of warm-up, then cycle regulator voltage

control (by disconnecting and re-connecting regulator

connector) and read voltage.

If voltage is 13.5 to 15.2, the regulator is okay.

If voltage is not within 13.5 to 15.2 volts, leave en-

gine running at 1500 rpm or above and:
a. Disconnect four terminal connector and remove

regulator cover. Then re-connect four terminal

connector and adjust voltage to i4.2 to 14.6.

(Refer to Step 6 and fig. 6c).

b.
Disconnect four terminal connector and reinstall

regulator cover, then reinstall connector.

c. Continue running engine at 1500 rpm for 5-10

minutes to re-establish regulator internal

temperature.

d. Cycle regulator voltage by disconnecting and re-

connecting regulator connector. Read voltage. A

reading between 13.5 and 15.2 indicates a good

regulator.

CAUTION: Be sure four terminal regulator

connector is disconnected when removing or in-

stalling cover. This is to prevent regulator

damage by short circuits.

DELCOTRON OUTPUT TEST

Ammeter Method (Fig. 8c)

1.
Disconnect the battery ground cable at the battery.

2.
Disconnect the red wire at Delcotron battery termi-

nal and connect an ammeter in series between the

wire and terminal.

3.
Connect a voltmeter from battery terminal to a good

ground on the generator.

4.
Disconnect the F-R terminal connector at the

Delcotron.

5. Connect the jumper wire between Delcotron "F" and

battery terminals.

6. Connect the battery ground cable at the battery.

7. Connect an adjustable carbon pile across the battery

posts.

8. Start the engine and slowly bring the speed to 1500

RPM and at the same time adjust the carbon pile

load to hold the voltage at 14 volts.

9. Read the amperage and compare with a specifications

chart.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-J2

Fig.
8c—Ammeter Method Test Connections

10.
Turn off ignition, disconnect battery ground cable,

and remove all test equipment.

11.
li the Delcotron meets the test specifications, the

problem is not in the generator.

12.
Ti the Delcotron fails to meet the test specifications,

remove it and perform bench tests and make repair

needed.

DELCOTRON DIODE AND FIELD TEST (Fig. 9c)

NOTE:
These tests will indicate good,, shorted

or open field or shorted diode but will not indi-

cate a failed open diode. If output was low and

following tests show good, refer to service op-

erations to determine cause and repair.

1.
Disconnect battery ground cable at battery.

2.
Positive diodes (Test A) connect an ohmmeter be-

tween "R" terminal and "BAT" terminal and note

Fig.
9c-Deicotron Diode and Field Test
reading, then reverse the leads at same terminals

and note this reading. Meter should read high re-

sistance in one direction and low in the other.

3.
Negative diodes (Test B) connect ohmmeter between

"R" terminal and "GRD" and note reading, then

reverse the leads and note this reading. Meter

should read high in one direction and low in the

other.

NOTE:
A high or low reading in both directions

indicates a defective diode.

4.
Open Field Check:

a. Connect an ohmmeter from "F" terminal to

"GRD"
terminal stud and note reading on the

lowest range scale. Meter should read 7 to

20 ohms.

b.
If meter reads zero or excessively high resist-

ance, the Delcotron is faulty.

5. If above tests indicate a defective Delcotron, remove

and completely check Delcotron as outlined under

''Service Operations".

INDICATOR LAMP/INITIAL FIELD

EXCITATION CIRCUIT TESTS (Fig. 10c)

On standard models the indicator lamp circuit provides

initial field excitation (causing lamp to glow). The light

is cancelled by closing the field relay which applies bat-

tery voltage to both sides of bulb (bulb goes out).

The indicator light should glow when ignition switch is

"ON"
and go out almost immediately when engine starts.

Ammeter equipped vehicles use the same initial field

excitation and control circuits as the indicator lamp ex-

cept the lamp is omitted. The continuity tests on both

type vehicles can be made as follows:

If Lamp Fails to Glow or Ammeter Fails to

Function the Possible Causes are:

1.
Faulty bulb or bulb socket.

2.
Faulty ammeter.

3.
An open circuit in wiring, regulator, or field.

4.
A shorted positive diode—(may also cause glow with

ignition switch "OFF").

TEST AS FOLLOWS:

1.
Disconnect connector from regulator and turn

ignition switch to "ON". Connect a test lamp from

connector terminal "4" to ground (fig. 10c, Step 1)

and note test lamp.

a. Lamp fails to glow—check for faulty bulb, socket

or open circuit between switch and regulator con-

nector. Repair as needed.

b.
Light goes on—failure is in regulator, Delcotron,

or wire between "F" terminals on regulator and

Delcotron. Go to Step 2.

2.
Disconnect lamp lead at ground end and connect be-

tween connector "F" and "4" terminals (fig. 10c,

Step 2), and note lamp:

a. Test Lamp glows—problem is in regulator. An

open circuit in regulator or relay is stuck dosed.

See "Service Operations" for repair.

b.
Fails to glow—problem is in wire between "F"

terminals on generator and regulator or infield

windings. Go to Step 3.

3.
Disconnect test lamp at connector "F" terminal and

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-13

F 2 3 4

f 2 3 4

F 2 3 4

Fig.
10c—Initial Field Excitation Circuit Tests

connect to "F" terminal on Delcotron (fig. 10c,

Step 3), and note lamp:

a. Lamp glows-an open circuit in wire between "F"

terminals—correct as needed.

b.
Fails to glow—Delcotron field has open circuit,

see "Service Operations" to repair %

If Lamp Fails to Go Out, or if Ammeter Shows

Discharge the Possible Causes are:

1.
Loose drive belt—adjust as necessary.

2.
Faulty field relay—(see relay test and adjustment).

3.
Defective Delcotron—(see Delcotron output test).

4.
At normal idle—parallel resistance wire open (see

Resistance test). On ammeter models the initial

field excitation wire to "ACC" terminal is open.

5. Switch off—positive diode shorted (see Diode test).

FIELD CIRCUIT RESISTANCE

WIRE CHECKS

The resistance wire is an integral part of the ignition

harness. However, the resistance wire is not solderable;

it must be spliced with a crimp-type connector. It is

rated at 10 ohms, 6.25 watts minimum.

The check for an open resistor or field excitation wire

(connected to the ignition switch "ACC" terminal) is as

follows:

1.
Connect a test lamp from the wiring harness con-

nector terminal "4" to ground as shown in Figure

10c (Step 1).

2.
Turn the ignition switch to the "ON" position and

note test bulb.

a. Test lamp glows—resistance is O.K.

b.
Test lamp does not glow—the resistor is open

circuited—note also that dash lamp does not glow

during this test because series resistance of the

2 bulbs causes amperage to be too low.
VOLTMETER

3 4

WIRING*
HARNESS

CONNECTOR

Fig.
11c—Testing Field Relay

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-14

VOLTMETER

WIRING HARNESS

CONNECTOR

Fig.
12c—Field Relay Closing Voltage Test

FIELD RELAY CHECKS AND ADJUSTMENT

To check for a faulty relay proceed as follows:

1.
Connect a voltmeter into the system at the regulator

No.
2 terminal to ground (fig. lie).

2.
Operate the engine at fast idle (1500 to 2000 rpm) and

observe voltmeter reading.

3.
If voltmeter shows zero voltage at regulator, check

circuit between No. 2 terminal on regulator to "R"

terminal on Delcotron.

4.
If voltage at regulator exceeds closing voltage
Fig.
13c—Adjusting Field Relay Closing Voltage

specification and light remains on, regulator field

relay is faulty (Refer to specifications). Check and

adjust regulator as follows:

CLOSING VOLTAGE ADJUSTMENT

•1.
Make connections as shown in Figure 12c using a 50

ohm variable resistor.

NOTE: This gives us a variable resistance in

series from a hot lead to the relay coil.

2.
Turn resistor to "open" position.

3.
Turn ignition switch off.

4.
Slowly decrease resistance and note closing voltage

of the relay. Adjust by bending heel iron in the man-

ner illustrated in Figure 13c.

OTHER HARNESS CHECKS

Other wires in the charging system harness need be

checked for continuity by use of an ohmmeter or a test

ligjit (12 Volt). Connect the test so the wire in question is

in series in the test circuit.

SERVICE OPERATIONS

Service Procedures described in this section are for

the 5.5" aluminum and 6.2" perforated stator Delcotrons

(fig. 14c). Where important differences are encountered

separate mention will be made of the two generators.

GENERATOR

REMOVAL AND INSTALLATION

1.
Disconnect the battery ground strap at battery to

prevent damaging diodes.

2.
Disconnect wiring leads at Delcotron.

3.
Remove generator brace bolt, (if power steering

equipped, loosen pump brace and mount nuts) then

detach drive belt (belts).

4.
Support the generator and remove generator mount

bolt (6.2" Delcotron uses 2 mount bolts) and remove

from vehicle.
5.
Reverse the removal procedure to install then adjust

drive belt.

PULLEY REPLACEMENT

5.5" Delcotron

Single Groove Pulley

1.
Place 15/16" box wrench on retaining nut and insert

a 5/16" alien wrench into shaft to hold shaft while

removing nut (fig. 15c).

2.
Remove washer and slide pulley from shaft.

3.
Reverse Steps 1 and
2
to install, use a torque wrench

with a crow-foot adapter (instead of box wrench) and

torque the nut to 50 ft. lbs. (fig. 16c).

Double Groove Pulley

1.
Place a 15/16" socket (with wrench flats on the drive

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-15

L
RELAY

TERMINAL "F" TERMINAL

"BAT" \ ' /

TERMINAL
/ / /
GRD7
TERMINAL

5.5" SERIES ID DELCOTRON
"BAH"

TERMINAL

^Vs^^^^lijBii^^8C^3^SH|j^^^^^^sH^^Bf- y/

RELAY ^^^"^^^jWwIi^^^^ RELAY

6.2" SERIES 2D, TYPE 150 DELCOTRON

Fig.
14c—Delcotrons - Full View

end or use Adapter J-21501 and a box wrench) on re-

taining nut, insert a 5/16" alien wrench through

socket and adapter into hex on shaft to hold the shaft

while removing the nut.

2.
Remove washer and slide pulley from shaft.

3.
To install, slide pulley and washer on shaft and start

the nut.

4.
Use the socket and adapter with a torque wrench and

tighten-nut to 50 ft. lbs. torque.

BRUSH
REPLACEMENT

6.2"
Delcotron

1.
Remove two nuts retaining the blade connectors and
remove the connectors (fig. 17c). Slide the indicator

light relay wire from the terminal post.

2.
Remove two screws retaining the capacitor and brush

holder to rear end frame, Remove brush holder.

3.
To install brushes, push brushes into holder and

install pin to keep the brushes in holder.

4.
Attach brush assembly and condenser to the end

frame with hex-head stud on the .left side only.

Fig.
15c—Pulley Removal

Fig.
16c—Torqulng Pulley Nut

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL
6Y-16

POINT
OPENINGJL

Fig. 17c-6.2"
Brush
Holder
Assembly

5. Rearrange leads as shown in Figure 18c with right-

hand brush lead connected under the right hand hex-

head stud.

6. Remove pin and attach terminal cover with two

screws, making sure leads are not caught under-

neath the cover.

DOUBLE CONTACT REGULATOR

While most regular adjustments are made on the vehi-

cle as outlined under "Maintenance and Adjustments",

the regulator may be removed for field relay point and

air gap adjustment. However, voltage regulating contacts

should never be cleaned as they are made of special

material that may be destroyed by cleaning with any

abrasive material.

NOTE:
A sooty or discolored condition of the

contacts is normal after a relatively short

period of operation.
Fig. 19c—Checking Field Relay Point Opening

REMOVAL AND INSTALLATION

To remove the regulator assembly, disconnect the bat-

tery ground cable and the wiring harness connector at the

regulator, then remove the screws securing the regulator

to the vehicle.

Electrical settings must be checked and adjusted after

making mechanical adjustments. Before installing regu-

lator cover, make sure the rubber gasket is in place on

the regulator base.

MECHANICAL ADJUSTMENTS

NOTE:
Only an approximate voltage regulator

air gap setting should be made by the "feeler

gauge" method.

BRUSH

LEAD

BRUSH

LEAD
RELAY
^B-/lliLlK
CONDENSER

LEAD
GROUND
LEAD

STUD
AIR GAP

(Check
With
Points

Just
Touching)

Fig.
18c—Lead
Arrangement
after
Assembly
Fig. 20c—Checking Field Relay Air Gap

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-17

Field Relay Adjustment touching (fig. 20c). The air gap normally need not be

adjusted. If the point opening and closing voltages

1.
Point Opening: The point opening is checked as il- are within specifications, the relay will operate

lustrated in Figure 19c. If adjustment is necessary, satisfactorily even though the air gap may not be

carefully bend the armature stop. exactly according to specifications. If adjustment is

2.
Air Gap: Check the air gap with the points just necessary, bend the flat contact spring.

CHEVROLET CHASSIS SERVICE MANUAL