tow OPEL GT-R 1973 Owner's Manual

OPEL 1900 AND MANTA STEERING COLUMN ASSEMBLY 3E.35
II
OPEL 1900 AND MANTA STEERING COLUMN
ASSEMBLY
CONTENTS
SubjectPage No.
DESCRIPTION AND OPERATION:
Description and Operation of Directional Signal
Lever. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Description
andOperationofHorn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Description of Steering Column Assembly
. . . . . . . . . . . . . .DIAGNOSIS: (Not Applicable)
MAINTENANCE AND ADJUSTMENTS: (Not
Applicable)
MAJOR REPAIR:
3E-353E-363E-36
Removal and Installation of Steering Column
Assembly
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RemovalandInstallationofSteeringWheel. . . . . . . . . . . .Disassembly and Reassembly of Direction Signal
Switch
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Disassembly and Reassembly of Steering and
Ignition Lock Cylinder, and Electrical Switch
from Mast Jacket Assembly
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .SPECIFICATIONS:
Steering
ColumnSpecifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3E-363E-383E-393E-403E-41
DESCRIPTION AND OPERATIONDESCRIPTION AND OPERATION OF
DIRECTIONAL SIGNAL LEVERhigh to low beam or vice versa. On all
19M) Rallye
cars, when switching from low to high beam posi-
tion, with the fog lamp instrument panel switch ON
The direction signal switch lever is a multi- purpose
lever controlling direction signals, passing signal and
headlight high and low beams. See Figure
3E-2.The dire&M signal lever is provided with a two-
step mechanism for operation of headlight high and
low beams, and passing signal (not in N.J.). With
headlights off, moving the lever repeatedly towards
steering wheel flashes headlights as a passing signal.
With headlights on, moving the lever repeatedly to-
wards steering wheel up to first stop also flashes
passing signal regardless whether or not the direction
signals are switched on. When the lever is moved up
to the second stop, the headlights are changed from
SE.2Figure
3E-2 Directional Signal Lever Position for
Headlamp Operation

GT STEERING COLUMN ASSEMBLY3E- 47
2. Disconnect ignition (white) wire set plug.
3. Remove steering lock retaining screw. See Figure3E-20.Figure 3E-20 Steering Lock Retaining Screw
4. Remove direction signal switch lever.
5. Remove three screws securing signal switch cover
to housing.
6. To remove housing cover, (a) pull cover toward
direction signal switch and move it slightly to the
right. See Figure
3E-21. (b) Turn cover toward the
left and move it further to the right so that the left
retaining screw ear is positioned under the left signal
switch return cam. See Figure
3E-22. (c) Insert direc-
Figure 3E-2 1tion signal switch lever into oblong opening in cover
and push steering lock into housing and remove
cover. See Figure
3E-37.Figure
3E-22Figure 3E.23
7. Remove ignition switch electrical unit. See Figure3B24.
8. Remove wires from connector plug making certain
to note location of each.
9. Tape wire ends together and remove electrical unit
and wire harness.
Installation1. Position electrical unit wire harness through col-
umn and reconnect to connector plug.

WHEELS AND TIRES36-63would require inflation pressures above the maximum allowable, speed must be
limited to 75 miles per hour.
3.Cool tire inflation pressure: After vehicle has been inoperative for 3 hours
or more, or driven less than one mile. Hot tire inflation pressure: After vehicle
has been driven
10 miles or more at 60-70 MPH.
4.Vehicles with luggage racks do not have a vehicle load limit greater than
specified.
5. When towing trailers, the allowable passenger and cargo load must be
reduced by an amount equal to the trailer tongue load on the trailer hitch.
Torque SpecificationWheelNuts
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65lb.ft.
IFigure 3G-8 Wheel and Tire - Exploded View

PROPELLER SHAFT AND CENTRAL JOINT4A- 5
1. Check condition of support cushions. If new cush-
ions are installed, torque to 29 lb. ft. See Figure 4A-6.
2. Install ball bearing into rubber cushion with the
flange facing toward front of car. Pack area in front
of bearing with water resistant grease. See Figure4A-7.
GAP BETWEEN BALL BEARING
AND SHEET METAL CASING
FILLED WITH GREASE
RUBBER CUSHION
BALL BEARING
TRAL JOINT
SUPPORT
RQUE TUBEa.7
Figure 4A-7 Torque Tube Bearing Installed
3. Install support bracket onto torque tube in such a
manner that one cushion is in place, then pry the
other cushion into place with a screwdriver. Torque
attaching bolts to 15 lb. ft.
4. Install drive pinion extension shaft into torque
tube from the rear. Tap in place with soft face mallet.
5. Install flange. Tap-flange onto drive pinion exten-
sion shaft, with a soft face mallet, at least far enough
to install nut.
6. Assemble flange holder J-8614 to flange, install
new self-locking nut and torque to 87
lb.ft.7. Install torque tube assembly onto differential car-
rier using only three of the four bolts. The fourth bolt
will be used later to install the brake pipe bracket.Figure
4A-8 Installing Support Bracket on TorquelTube8. Position floor jack under torque tube and raise it
far enough to install central joint support to under-
body bolts finger tight. Remove jack.
9. Jounce rear of car so springs will assume normal
position and torque the central joint support to un-
derbody bolts to 36 lb. ft.
10. Align mating marks of universal joint and flange,
connect universal joint to flange with respective bolts
and lock plates. Torque nuts to 11 lb. ft. Bend lock .
plate tangs to retain bolts.
11. Assemble parking brake cable equalizer and re-
turn spring to brake rod and adjust to specifications.
12. Connect brake line bracket to torque tube.
13. Remove supports
f&n rear of car and lower to
the floor.

6. Before installing, shims must be measured to in-
sure that the proper thickness is being used. Install
shims of correct thickness to obtain desired clearance
and reassemble and install pinion shaft lock pin. In-
stall thrust washers with concave side towards differ-
ential case.
7. Using Special Tool J-24093, along with a foot-pound torque wrench, check torque to turn gears
using the following procedure:
a. Install axle shaft into a vise and position differen-
tial case onto axle shaft. See Figure
4B-25.Figure 48-23 Raising Side Gear Against Case
Figure 48.24 Measuring Concave Washer Thickness
AX,EXAMPLE:
1.Dial indicator reading * .095.
2. Subtract concave thrust washer thickness
+ -.oso.
3.Total + ,045.
4.Subtract an additional .002 *.002.
5. Shim thickness to be used
+ .043.
5. Turn case over and repeat the above procedure to
check other side gear to differential case clearance.Figure 48.25 Axle Shaft Installed in Vise
b. Insert Special Tool J-24093 into opposite side gear,
attach a torque wrench, and check torque to rotate
gear. S& Figure
4B-26. Permissible torque to turn
gears is 14
l/2 to 17 l/2 footpounds.
c. It is necessary to check rotating torque of both side
gears.8. If torque is not correct, it will be necessary to
reshim differential gears. Add first at one side one
shim of the next higher or lower thickness. If this is
not enough, reshim both sides completely.
9. Install ring gear on case making certain their mat-

5A- 61973 OPEL SERVICE MANUAL
ing on dusty and sandy roads - the filter and sound
deadener should occasionally be replaced. To do so,
brake booster has to be removed without detaching
brake master cylinder.
Proceed as follows:
1. Remove protective cap (boot).
2. On the GT only, pry retainer from housing
using a screwdriver. See Figure
SA-6.Figure 5A-6 Brake Booster Filter (GT)
3. With a pointed tool remove air silencer and filter
out of control housing bore and pull it off thrust rod.
4. Install new filter and air silencer. On the GT, the
smooth side of the filter must face towards the inside.
The radial slots in filter and deadener must be stag-
gered to each other by 180 degrees.
5. Slide retainer over control housing (GT only) and
seal it with light plastic hammer strokes. Slide pro-
tective cap over control housing and slip it onto
brake booster housing.
VACUUM CONTROL VALVE SERVICE
A vacuum control valve is installed into the vacuum
hose between intake manifold and brake booster. It
serves to prevent air from flowing back (vacuum
release), when engine is shut off.
The vacuum control valve cannot be disassembled
and has to be replaced, if defective. On replacement,
note the following:
1. The vacuum control valve should be located near
the intake manifold. Therefore, the short vacuumhose has to be installed between intake manifold and
vacuum control valve and the long hose between
vacuum control valve and brake booster.
2. The arrows on the vacuum control valve housing
must point towards the intake manifold, otherwise
no air can be drawn out of the brake booster which
renders the brake booster ineffective.
3. The connections of the vacuum hoses to the intake
manifold, vacuum control valve and brake booster
must be airtight. For this reason make sure. that the
hose clamps are properly installed.
MAJOR REPAIR
BRAKE BOOSTER REMOVALAND INSTALLATION
Removal
1. Disconnect brake pipes from master cylinder.
Place a cloth under the master cylinder and brake
pipes to absorb any brake fluid drippings.
2. Disconnect vacuum hose from brake booster.
3. Remove four nuts and washers attaching brake
booster to brake booster support.
4. On the GT only, remove master cylinder support
to fender skirt bolts.
5. On the GT, loosen thrust rod lock nut and un-
screw the piston push rod while holding the master
cylinder brake booster assembly. On the Opel
1900and Manta, remove the nut and bolt attaching clevis
on the pedal.
6. Remove assembly from car.
7. Disconnect master cylinder from brake booster.
Installation
CAUTION: Fasteners in the folkwing steps are im-
portant attaching parts in that they could affect the
performance of vital components and systems, and-
/or could result in major repair expense. They must
berep/aced, with one of the same part number or with
an equivalent part if replacement becomes necessary.
Do not
use a replacement part or lesser quality or
substitute design. Torque values must be used as
specified during reassembly to assure proper reten-
tion of these parts.1. Using a new front housing seal, assemble master

DISC BRAKES5B- 11
rLF 5.2. RUBBER FLUID SEALS6.3. HOLLOW PISTONS7.
AL5
3Figure 58.21 Left Front Disc Brake
- Emloded View
the piston circumference by its inherent tension. See
Figure
5B-21. Both pistons are hollow. The open end
of each piston faces the brake disc.
A sheet metal spacer plate with two impressions for
preventing the piston from rotating is installed be-
tween each piston and friction pad and secured by
the friction pad dowel pins. The two friction pads are
positioned on the right and left of the brake disc
recesses in the caliper halves. Each friction pad con-
sists of a backing plate with friction material, which
is abrasive-coated, bonded to it. The friction pad
assemblies are held in position in the brake caliper by
two dowel pins, secured by slit dowel pin retainers,
and by a cross-shaped retaining spring which is pre-
loaded and positioned under the dowel pins, thus
pressing the friction pads and spacer plates firmly
against the pistons. The front brake line leading from
the brake master cylinder attaches to a distribution
tee from which a brake line leads to each front wheel
caliper. The caliper bores are interconnected by fluid
ducts within the caliper halves.
The front wheel disc brakes have self-adjusting pis-
tons. See Figure
5B-22.The adjustment of the pads is effected by the pistons
which push the friction pads ahead towards the
brake disc for a distance equivalent to the amount of
friction pad wear. This means that the greater the
wear the closer the pistons move towards the brake
disc. A running clearance exists between friction
pads and brake disc when the brakes are in “off”
position. This running clearance is provided by the
rubber fluid seals which are positioned in the caliper
half bores and which tightly grip and exert their
pre-load pressure on the pistons. The rubber fluid
seals also prevent the pistons from being pushed into
the caliper half bores more than the distance equiva-
lent to the running clearance. As the friction pads are
adjusted by the pistons, there must be no static pres-
sure in the front brake circuit when the brakes are in“OR position. Non-existence of a static pressure in
the front brake circuit is achieved by eliminating the
check valve in the brake master cylinder on the front
brake circuit. During brake application the pressure
from the brake master cylinder is transferred to the
pistons in the brake caliper. The pistons move ahead
and press the friction pads against both friction
SW-faces of the rotating brake disc. The force exerted on
the brake pedal determines the pressure of the fric-
tion pads against the brake disc. On releasing the
brake pedal, the brake lines of the front brake circuit,
including the caliper half bores, are relieved of
hy-OPERATION

5B- 121973 OPEL SERVICE MANUAL
A = BRAKE ON
THE RUBBER FLUID SEAL TIGHTLY GRIPPING PISTON
IS DEFLECTED IN DIRECTION OF PISTON TRAVELAFRICTION PAD
BRAKE DISCRUBBER FLUID SEALBRAKE
IICALIPER
IPISTON
I
CE BETWEEN RUNNING CLEARAN
FRICTION PAD AND BRAKE DISC
B = BRAKE OFFBTHE PISTON IS RETRACTED BY THE AMOUNT OF
RUBBER FLUID SEAL DEFLECTION. THIS AMOUNT
IS EQUAL TO RUNNING CLEARANCE.SBZZ
Figure 58-22 Rubber Fluid Seal -Automatic Piston Retractiondraulic pressure, and the friction pads and pistonsmove away from the brake disc, leaving a small run-
ning clearance. The brake disc can now rotate freely.
The amount of brake travel is dependent upon the
amount of running clearance. For this reason therunout of the brake disc should be checked, besides
bleeding of the brake system and adjusting the rear
brake shoes, when the pedal free travel is too great.during braking, the rubber seals in the annular
grooves of the brake caliper bores deflect laterally in
the direction of piston movement. See Figure
5B-22,View (A). The seal remains deflected for the duration
of the braking operation. After braking, the caliper
bores are relieved of hydraulic pressure and the rub-
ber seals resume their normal position, thus pulling
or retracting the pistons. The distance traveled by
the pistons is equal to that of the running clearance
between brake disc and friction pads.
The running clearance between brake disc and
fric-tion pads is attained as follows: When the pistons in
the caliper halves are moved towards the brake discThe shifting of the pistons in the direction of the
brake disc due to friction pad wear has no effect on
the running clearance. The running clearance re-mains the same in all piston positions.
DIAGNOSIS
DISC BRAKE TROUBLE DIAGNOSIS
ConditionPulls
Possible Cause
I. Incorrect tire
pressures.Correction1. Inflate evenly on both sides to
the recommended pressures (see
Owner’s Manual).

DISC BRAKES5B- 15
ConditionPossible Cause
2. Binding brake pedal
mechanism.Correction
2. Check and lubricate, ifnecessary.3. Corroded caliper
assembly.3. Clean and lubricate.
MAINTENANCE AND ADJUSTMENTSDISC BRAKE MAINTENANCE
Checking Brake Fluid Level
The brake fluid level in the brake fluid container
must be checked during predelivery inspection, then
every 3,000 miles during inspection and preventive
maintenance servicing.
The brake fluid level must not be higher than the
inscription “MAX” and must be at least up to
“MIN”. Replenish brake fluid, if necessary.
Because of the relatively large brake caliper bore
cross section and the self-adjustment of the disc
brakes, resulting in a greater piston travel to compen-
sate for friction pad wear, the brake fluid level drops
faster than in fluid containers for drum brakes with
their smaller wheel brake cylinders. For this reason
pay special attention to the fluid level in the brake
fluid container.
Drop of brake fluid level can be due to friction pad
wear and may not be due to leakage in the braking
system.On loss of brake fluid due to leakage, the brake sys-
tem must be checked thoroughly.
Friction Pad Adjustment
Friction pad adjustment is not necessary on the front
wheel disc brakes as this is done automatically by the
pistons in the brake calipers.
Lubricating Front Wheel Bearings
When removing one or both brake discs, check lu-
brication of front wheel bearings and the cavity of
the wheel hub and replenish if necessary (see operat-
ion
“Removing and Reinstalling Brake Disc”).
When carrying out other work on disc brakes which
does not necessitate the removal and installation of
the brake disc, lubricating wheel bearings is not
necessary.Checking Disc Brake Friction Pads for Wear
Whenever a disc brake equipped car is in for periodic
service, while the car is raised, the friction pads in
both brake calipers should be checked for wear by
making a simple measurement. Worn or oily friction
pads must be replaced.
Measure friction pad wear as follows:
1. Remove friction pads.
2. Using a one-inch micrometer, measure the thick-
ness of the pad and friction plate. See Figure
5B-23.Figure 58-23 Checking Brake Friction Pad Thickness
3. If any one of the four measurements is less than
-.280, replace all four friction pads. (Partial replace-
ment of friction pads would cause unequal braking.)
Removal and Installation of Friction Pads
1. Raise car and remove front wheels.
2. Drive dowel pins out of brake calipers toward
center of car. See Figure
5B-24. Dowel pins must be
driven inward because they are secured by enlarge
fluted inner ends.
3. Remove friction pads from brake calipers. See
Figure
5B-25.

58.201973 OPEL SERVICE MANUAL
half, and blow out pistons, carefully regulating air
flow. When removing pistons, proceed with extreme
caution and always keep the fingers ofthe hand hold-
ing the brake caliper away from the piston.
Figure 55.33 Removing Caliper Rim Half Piston
Figure 58-34 Removing Caliper Mounting Half Piston
4. Pry rubber fluid seals out of the annular grooves
in the caliper half bores. See Figure
5B-35.5. Check all parts of the brake caliper for wear. If the
caliper half bores are scored or rusted, use a new
complete brake caliper and friction pads. Small, light
rust spots in the caliper half bores or on the pistons
can be removed with fine emery cloth. If pistons are
damaged, even though the caliper half bores are inFigure 58-35 Removing Rubber Fluid Seal From
Caliper Boresgood condition, the piston must be replaced. The
rubber fluid seals and rubber seals with
clapp rings
for the pistons are to be replaced every time repair
work is carried out on the brake caliper.
6. Thoroughly clean all reusable parts
- complete
brake caliper and pistons
- with denatured alcohol
and dry with compressed air. Prior to cleaning, screw
bleeder valve out of caliper.
7. Lightly coat new rubber fluid seals with brake
fluid and insert fluid seals into grooves of brake
caliper bores.
8. Place brake caliper into vise to install pistons.
After installing one piston, change position of brake
caliper in vise to install second piston. The piston to
friction pad spacer plates should be used as a gauge
to locate relieved edge of piston at 20 degrees to
horizontal during piston installation. See Steps
9-IO-
11-12.9. Place caliper mounting half in vise and coat its
bore and piston lightly with brake fluid. Then push
piston, with hollow end towards brake disc, into the
caliper bore. Turn piston so that the relieved edge
faces downwards at an angle of 20 degrees and facing
in brake disc direction. The guide surface in the
caliper half recess at the brake pipe connection side,
will properly align the piston. Push piston into
caliper bore up to the stop.
10. Change position of brake caliper and install sec-
ond piston in the same manner.
11. Install new rubber seals with clamp rings. Make
sure that the rubber seals are properly seated on the