suspension OPEL GT-R 1973 Owner's Manual

3D- 301973 OPEL SERVICE MANUALFigure 3D-8 - Removing Clamp Bolt3. Remove cotter pin located on left and right tie rod
end and unscrew nut.
4. Using Tool J-21687, press tie rod ends out of
steering arms.
5. Disconnect steering gear housing from front sus-
pension cross member and remove steering gear
together with tie rods.
Installation . GTCAUTION: Fasteners are important attaching parts in
that they could affect the performance of vital com-
ponents and systems, and/or could result in major
repair expense. They must be replaced
with one of
the same part number or with an equivalent part if
replacement becomes necessary. Do not
use a re-
placement part of lesser quality or substitute design.
Torque values must be used as specified during reas-
sembly to assure proper retention of these parts.
1. Position steering gear on front suspension cross
member and torque attaching bolts to 18
lb.ft.2. Position tie rod ball studs in steering arms; install
nuts and torque to 29 lb.ft. Lock in position with new
cotter pins.
3. Fully turn steering wheel so that flat or cutout
surface on lower portion of steering shaft is parallel
to flexible coupling bolt hole.
4. Install the lower end of steering shaft to the flexi-
ble coupling and adjust dimension between steering
wheel hub and direction signal switch housing cover
to
l/8 and 3/32 inch. Maintain adjustment by tight-
ening flexible coupling bolt and nut to 15 lb.ft. Lock
the bolt and nut in position with lock-plate tabs.5. Reinstall stop bolt into steering column.
6. Full turn steering wheel both right and left. If any
resistance is noticeable, it will be necessary to remove
the sleering column and correct the cause.
D. Installation (Opel 1900. Manta)CAUTION: Fasteners are important attachingparts in
that they could affect the performance of vital com-
ponents and systems, and/or could result in
maJbrrepair expense. They must be replaced with one of
the same part number or with an equivalent part if
replacement becomes necessary. Do not use a re-
placement part oflesser
quaky or substitute design.
Torque values must be used as specified during reas-
sembly to assure proper retention of these parts.
1. Prior to installation, set steering gear to high
point. The steering wheel spokes point downwards in
an oblique angle. The elongated cutout of the lower
steering mast must coincide with the clamp bolt hole
of the pinion flange.
2. Position steering gear on front suspension cross
member and torque attaching bolts to 29 lb.ft.
3. Position tie rod studs in steering arms. Install nuts
and torque to 29
Ib.ft. Lock in position with new
cotter pin.
4. Install the lower end of the steering shaft to flexi-
ble coupling and torque clamp bolt to 22
lb.ft.5. Attach guard plate to both side members and
lower deflector panel.
DISASSEMBLY AND ASSEMBLY OF
STEERING GEAR ASSEMBLY WITH TIE RODS
Disassembly - GT1. Carefully clamp gear assembly in soft jaw vise and
slip clamps and rubber bellows off gear housing to
expose area where ball joint screws into rack.
2. Bend up round edges of lockplates from tie rod
ball studs and disconnect tie rod ball studs from rack.
See Figure
3D-9). It is important that rack be held
secure with open end wrench to prevent damage to
rack teeth.
3. Loosen adjusting screw lock nut; remove adjusting
screw from steering gear housing, and take out thrust
spring and sintered bronze shell. See Figure
3D-11.4. Rotate gear assembly in vise so that pinion shaft
portion of assembly is held by vise, and remove pin-
ion nut, flat washer, and special washer.

STEERING GEAR ASSEMBLY30.33ble steering gear lubricant. Fill long end of housingbly. Under such circumstances, the bellows will be
with approximately 1 3/4 oz. steering gear lubricant.
drawn inward and jam into the rack teeth.
3. Reassemble pinion shaft into gear assembly so that
spline in pinion shaft meshes with twelfth tooth of
the rack. Use pinion mounting sleeve J-21712 during
installation of pinion shaft to avoid damage to “0”
ring in pinion bushing. When reassembling pinion
shaft into gear housing, be sure that pinion is so
positioned that bolt hole in pinion shaft flexible cou-
pling is on top and parallel to the rack. See Figure
3D-16.2. Insert long toothless end of rack into short end of
housing until rack ends (A) protrude equally out of
both ends of housing. See Figure
3D-16.Figure 3D-16
- Steering Gear Housing With Rack
Check to insure that three air channels of sintered
metal bushing are not obstructed by lubricant. If air
channels are blocked, a vacuum condition in the bel-
lows may result during operation of the gear assem-
SPECIFICATIONS
Tightening Specifications
PartLocation
BoltBolt
Nut
NutNut
Bolt
Bolt
NutNut
Nut4. Reassemble special washer, flat washer, and new
pinion nut onto pinion shaft. Torque pinion nut to 11
lb.ft. Do not exceed torque due to possibility of jam-
ming gear.
5. Place sintered bronze shell into steering gear hous-
ing and till adjusting hole with suitable steering gear
lubricant.
6. Reassemble thrust spring, adjuster screw and lock-
nut on gear assembly. Torque locknut to 43
Ib.ft.7. Screw ball stud of the axial joint together with stop
plate onto both ends of the rack. Torque to 47
lb.ft.Counterhold rack with open-end wrench.
8. Slide rubber bellows onto axial joint and steering
gear housing. Attach rubber bellows with loose
clamp and clamping wire. Check that rubber bellows
is not twisted.
FlexibleCouplingClamp(GT)
Flexible Coupling Clamp (1 900
- Manta) _....,,,,,,....._...,,,,Tie
RodBall-Connects toRack (GT). . . . . .
BallStud - Axial Joint toRack (1900 - Manta)
Tie
RodLockNut(1900-Manta). . . . . .
Steering Gear Housing to Front Suspension
Crossmember (GT)
,,....._.._.................................................Steering Gear Housing to Front Suspension
Crossmember (1 900
- Manta) _...........................,...........Adjusting Screw Lock Nut.
.._.._....................................Pinion
. . . .._............_.......,,,,,.........................................,,,,..........,,Tie Rod to Steering Arm. .
.._.....................................
Torque
Lb.Ft..-
;“2
43
4749
18
29
43
:i

REAR SUSPENSION3F- 51
REAR SUSPENSION
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Description and Operation of Rear Suspension. . . . . .DIAGNOSIS: (Not Applicable)
MAINTENANCE AND ADJUSTMENTS: (Not
Applicable)
MAJOR REPAIR:
Rear Shock Absorber Removal and Replacement . .
Rear
SpringRemovalandInstallation. . . . . . . . . . . . . . . . . . . . . . . .LowerControlArmReplacement
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Stabilizer
RodReplacement. . . . . . . . . . . ~ . . . . . . . . . . . . . . . . . . . . . ..-....Track Rod Replacement
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .SPECIFICATIONS:
Rear
SuspensionSpecifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page No.3F-5
13F-513F-523F-533F-533F-533F-53
DESCRIPTION AND OPERATIONDESCRIPTION AND OPERATION OF REAR
SUSPENSIONAll Opels utilize the three link rear suspension ar-
rangement. This rear suspension consists of coil
springs, track rod, shock absorbers and lower control
arms.The coil springs set between two seats which arc
situated ahead of the rear axle housing.
The track rod is utilized on all models to control the
lateral stability of the rear axle assembly. It is of
tubular design. A stabilizer rod is used on all Wagons
as well as Fast Backs and Sedans. The GT is not
equipped with a stabilizer rod.
The lower control arms are of tubular design and
function as two links of the three link suspension
system. They are attached to the underbody through
brackets welded to the side rails and to the rear axle
assembly through the front portion of the spring seat
bracket. The lower control arms control the fore and
aft movement of the rear axle assembly.
The third link in this suspension system is the torque
tube which is connected to the differential carrier
and also to the underbody through rubber bushings
in the central joint support bracket.The torque tube in conjunction with the lower con-
trol arms absorb all acceleration and braking torque.
MAJOR REPAIR
REAR SHOCK ABSORBER REMOVALAND INSTALLATION
RemovalNOTE: The trim panel under the spare tire must be
removed on the GT to gain access to attaching nuts.
1. Remove upper attaching nut, retainer and rubber
grommet.
2. Remove lower attaching nut and rubber grommet
retainer, compress shock absorber and remove from
lower mounting pin.
Installation1. Replace upper and lower rubber grommets, if
necessary, before installing shock absorber.
2. Extend shock absorber and position in car. Attach
at lower end first, torque nut to 15 lb.ft. on the GT,
and torque to 47 lb.ft. on the Opel 1900
- Manta.

REAR SUSPENSION3F- 53
7. Remove jack stands.
LOWER CONTROL ARM REPLACEMENTRemovalThis operation can be performed with the vehicle
standing at curb height or elevated.
1. Disconnect parking brake cable from support
bracket on control arm.
2. Loosen and remove front and rear control arm
attaching bolts and remove control arm.
installation1. On
1900’s and Manta’s place a load of approxi-
mately 350 lbs. in luggage compartment or on the
GT, place a load of approximately 150
Ibs. on dri-
ver’s seat. Torque control arm attaching nut and
bolts to 18 lb.ft on
GT’s and 23 Ib.ft. on the 1900 -Manta.
2. Connect parking brake cable to support bracket on
control
ranI.
STABILIZER ROD REPLACEMENT
Removal1. Raise and support rear of vehicle.
2. Disconnect stabilizer rod to shackle bolts.
3. Disconnect stabilizer rod to underbody retainers
and work stabilizer rod out from under vehicle.
SPECIFICATIONS
REAR SUSPENSION SPECIFICATIONS
Tightening SpecificationsInstallation1. Work stabilizer rod into position and loosely at-
tach stabilizer to underbody retainers.
2. Connect stabilizer rod to shackles.
3. With the vehicle standing on its wheels or the rear
axle assembly lifted, tighten stabilizer rod to under-
body bracket bolts to 15 lb. ft.
4. Remove jack stands and lower vehicle.
TRACK ROD REPLACEMENT
Removal1. Lift rear of car and suitably support.
2. Disconnect track rod from rear axle and frame
side member.
Installation
1. Loosely connect track rod first to side member and
then to the rear axle.
2. On the
1900 - Manta, load luggage compartment
of vehicle with approximately 350 lbs. or on the GT,
place a load of approximately 150 lbs. on driver’s
seat and tighten track rod attaching bolts to specified
torque.
3. Remove supports (jack stands) and lower vehicle.
Use a reliable torque wrench. Specifications are for clean and lightly-oiled
threads.
Part
Nut
Nut
Nut
Bolt
Nut
Nut
Nut
BoltName
WheelNuts.
.._.._......._........................................................
Control Arm Attaching (GT) .._.._.,,,........,,.,,.......,,......,,,,......
Control Arm Attaching (1 900 - Manta) .,,...._...,,,,_.....,,.,...
Stabilizer Rod to Underbody Retainers ,....._.,.,,.,.....,,,....
Shock Absorber Lower Attachment (GT) . .._.....,._.._.,,,...
Shock Absorber Lower Attachment (1900 Manta) ,,.,
Shock Absorber Upper Attachment. .._.....................
Stabilizer Shackle to Axle Bracket .._._.._,...._..,,.,,.......,,,...
Torque
Lb.Ft.
65
16
23
15
1,5
47
1025

3F- 541973 OPEL SERVICE MANUAL/UPPER RUBBER
DAMPER
RINGCOIL SPRINGTRACK ROD
LOWER RUBBER
’DAMPER RING
REAR AX;E ASSEMBLY
COIL SPRING SEAT
STABILIZER ROD
$3SHOCK ABSORBER
LOWER CONTROLARM
Figure 3F.5 Exploded View Rear Suspension

WHEELS AND TIRES3G- 61Cornering Tread WearThe modern independently-sprung automobile al-
lows the driver to negotiate turns at a high rate of
speed with a greater feeling of safety. This fact is
responsible for a comparatively new type of tread
wear that can easily be mistaken for toe or camber
wear.When a car is making a turn, the tires are supposed
to be rolling in a circle. When the turn is made at
high speed, however, centrifugal force acting on the
car causes the tires to be distorted sideways and to
slip or skid on the road surface. This produces a
diagonal cross type of wear, which in severe cases
will result in a fine or sharp edge on each rib of the
tire treads.
Cornering wear can be distinguished from toe or
camber wear by the rounding of the outside shoulder
of the tire and by the roughening of tread surface in
this section denoting severe abrasion. See Figure
3G-7.No alignment or tire pressure cahnge can be made
that will relieve cornering wear. Only the driver can
effect a cure and that is by slowing down on curves.
Heel and Toe Tread WearHeel and toe wear is a saw-tooth effect with one end
of each tread block worn more than the other.
The end which wears is the one that first grips the
road when the brakes are applied. High-speed driv-
ing and excessive “se of the brakes will cause this
type of irregular tire wear. This type of wear will
occur on any type of block tread design. See Figure3G-7.
Heel and toe wear is not so prevalent on the rear tires
because of the propelling action which creates a
counteracting force which wears the opposite end of
the tread block. These two stresses on the rear tires
wear the tread blocks in opposite directions and re-
sult in more even wear while on the front tires, the
braking stress is the only one which is effective. This
may be counteracted by interchanging tires.
A small amount of irregular wear, slightly
saw-toothed in appearance, at the outer segments of tires
is a normal condition and is due to the difference in
circumference between the center and the outer
edges of the tire tread. This saw-toothed appearance,
however, will be exaggerated by underinflation, im-
proper toe-in, or both.Cupped or Scalloped Type Tire Wear
Cupping or scalloping is associated with wear on acar driven mostly at highway speeds without recom-
mended tire rotation. Factors which promote cup-
ping include underinflation, incorrect toe-in setting
or camber setting, and steady highway speeds on
smooth, paved surfaces as opposed to gravel or
rough asphalt.
The following recommendations suggest action that
may be taken to help prevent cupping.
1. Rotate tires as recommended in Figure
3G-6.2. Frequently inspect front tires for irregular wear
due to underinflation, improper toe-in setting, or
camber setting. Regardless of the original cause of
cupped tread wear on either front tire, no alignment
or balance job, however perfect, can prevent future
excessive wear of the spots. Once a front tire acquires
flat or cupped spots, additional wear will continue at
a rapid rate. At the time of correction, however, the
cupped tire should be interchanged with a rear tire
on which the tread runs true. The cupped tire will,
to a certain degree, true itself on a rear wheel.
Although not normally the cause of cupping, the
following factors can contribute to the problem.
Looseness of parts in the suspension system, such as
worn steering knuckle ball joints, loose wheel bear-
ings, inoperative shock absorbers, and any excessive
looseness throughout the steering system all tend to
allow the front wheels to kick around and, if any of
the wheel alignment factors are incorrect, irregular
spotty tire tread wear of one type or another may
result.
Wobble or runout of a tire, either front or rear, due
to bent wheel or to tire being improperly mounted
will cause uneven wear.
MAINTENANCE AND ADJUSTMENTSDEMOUNTING AND MOUNTING
TUBELESS TIRESDue to “se of symmetrical rims, tires must be
mounted over the narrow rim shoulder i.e., over out-
side rim flange.
When demounting a tubeless tire “se care to avoid
damaging the rim-seal ridges on tire beads DO NOT
USE TIRE IRONS TO FORCE BEADS A WA Y
FROM WHEEL RIM FLANGES.
When tire is removed, inspect it carefully to deter-
mine whether loss of air was caused by puncture or
by improper
tit of beads against rim flanges. If im-
proper fit is indicated, check wheel as follows: Do
not reuse dented rims.

REAR AXLE48. 9
MAJOR REPAIRREMOVAL AND INSTALLATION OF REAR AXLE
ASSEMBLYRemoval
1. Raise rear of car with floor jack under differential
carrier and position jack stand under jack bracket on
each side of car. Remove rear wheel assemblies and
one brake drum.
2. Disconnect parking brake cable equalizer and re-
turn spring from brake rod.
3. Detach parking brake cable from actuator lever
and backing plate at wheel with brake drum
removed. Disconnect cable from lower control arm
brackets and pull loose end over exhaust system.
4. Disconnect shock absorbers at lower end.
5. Disconnect track rod at left end.
6. On cars equipped with a stabilizer rod, disconnect
the shackles at rear axle housing.7. Disconnect universal joint from pinion flange and
support or tie propeller shaft out of way after mark-
ing mating areas. If propeller shaft is removed, install
plug in rear of transmission to prevent loss of lubri-cant.8. Disconnect brake hose from brake pipe at differen-
tial and remove retaining clip.
9. Lower rear axle assembly far enough to remove
coil springs.
10. Remove central joint support bracket to under-
body retaining bolts.
11. Disconnect lower control arms at rear axle assem-
bly bracket and roll the assembly from under the car.
See Figure
4B-2.Installation
CAUTION: Fasteners in the following steps are impor-tant attaching parts in that they could affect the
performance of vital components and systems, and-
/or coo/d
resuJt in major repair expense. They must
be rep/aced with one of the same part number or withREAR SHOCK ABSORBERS
SPRING SEAT
4B-1Figure
4B-l Differential and Rear Suspension Assembly

5B- 10 1973 OPEL SERVICE MANUAL
DISC BRAKES
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Operation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . * . . . . . . . . . . . . . . . . . .DIAGNOSIS:
DiscBrakeTroubleDiagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAINTENANCE AND ADJUSTMENTS:
Disc Brake Maintenance
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Checking Disc Brake Friction Pads for Wear
. . . . . . . . . .Replacing Friction Pads
Checking Brake Disc for Lateral
Runout. . . . . . . . . . . . . . . . . .MAJOR REPAIR:
RemovingandInstallingBrakeCaliper. . . . . . . . . . . . . . . . . . . . . .Removing and Installing Brake Disc
. . . . . . . , . . . . . . . . . . . . . . . . . .
RemovingandInstallingBrakeDiscShield. . . . . . . . . . . . . .Disassembly and Assembly of Brake Caliper
. . . . . . . . . .SPECIFICATIONS:
Disc Brake Specifications
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page No.
58-1058-l
1
58-12
58-15
SB-15
5&17
56-17
58-17
58-195519
58-21
DESCRIPTION AND OPERATION
DESCRIPTIONThe front wheel disc brake consists of two major
parts: The brake disc and the brake caliper with the
two friction pads. See Figure
5B-20.The brake disc is attached to the inside of the wheel
hub flange by four bolts and centered on a shoulder
of the hub. The brake caliper consists of two halves:
the mounting half, arranged on the inside of the
brake disc, and the rim half. The two halves are
firmly attached to each other by four bolts. Two
flanges on the mounting half serve as attachment of
the brake caliper to the steering knuckle. The brake
caliper is positioned behind the front suspension
cross member at steering knuckle spindle level. It is
attached to the steering knuckle by two bolts. Both
caliper halves act as brake cylinders and each houses
a piston and a fluid seal. The fluid seal, of square
cross section, is positioned in an annular groove of
the caliper bore, preventing fluid leakage past the
piston and entry of water and dirt. The pistons and
caliper half bores are protected against entry of waterFigure 58.20 Left Front Disc Brake Assembly
and dirt in brake disc direction by a rubber seal, held
on the caliper half collar by a clamp ring and against

DISC BRAKES5B- 13
Condition
Possible CauseCorrection
2. Front end out of line.2. Check and align to manufac-
turer’s specifications.
3. Unmatched tires on sameaxle.3. Tires with approximately the
same amount of tread should be used
on the same axle.
4. Restricted brake tubes
or hoses.4. Check for soft hoses and damaged
lines. Replace with new hoses and
new double-walled steel brake
tubing.
5. Malfunctioning caliper
assembly.5. Frozen caliper
- check for
stuck or sluggish pistons, proper
lubrication.
6. Defective or damaged
shoe and lining (grease or
brake fluid on lining or
bent shoe).6. Install new shoe and lining in
complete axle sets.
7. Malfunctioning rear
brakes.7. Check for brake adjustment,
defective lining (grease or brake
fluid on lining) or defective wheel
cylinders. Repair as necessary.
8. Loose suspension parts.
9. Loose calipers.8. Check all suspension mountings.
9. Check and torque bolts to
specifications.
Brake Roughness or Chatter
(Pedal Pulsates)
1. Excessive lateralrunout.1. Check per instructions and
replace or machine the rotor, if not
within specifications.
2. Parallelism not within
specifications.2. Check per instructions and replace
or machine the rotor, if not within
specifications.
3. Wheel bearings not
adjusted.3. Adjust wheel bearings to correct
specifications.
4. Rear drums out of round.4. Check runout and, if not within
specifications, turn the drums within
specifications.
5. Shoe reversed (steel
against iron).5. Replace shoe and lining and
machine rotor within specifications.
ExcesGve Pedal Effort1. Malfunctioning power
brake.1. Check power brake and repair,
if necessary.

6A- 8 1973 OPEL SERVICE MANUAL
Actual adjustment is made by backing off adjusting
nut at the rocker arm until clearance exists between the valve stem, rocker arm, and lifter. Then slowly
tighten adjusting nut until clearance is eliminated.
When clearance is eliminated, turn adjusting nut one
full turn (clockwise). This positions the hydraulic
piston of the hydraulic lifter mid-point in its total
available travel, and no further adjustment is re-
quired.
MAJOR REPAIR
ENGINE ASSEMBLY REMOVAL AND
INSTALLATION
Removal (Opel 1900 and Manta)’
The engine assembly on the Opel 1900 and Manta
can be removed together with the transmission
through the top of the engine compartment.
1. Remove hood (scribe hood hinge to hood mount-
ing location).
2. Disconnect battery negative cable.
3. Drain coolant at lower radiator hose.
4. Remove upper and lower radiator hoses.
5. Remove radiator and fan
shrbud.
6. Disconnect heater hoses.
7. Disconnect brake booster
vacuum hose.
8. Remove air cleaner.
9. Disconnect electrical connections and accelerator
linkage. 10. Remove console.
11. Remove shift lever boot, plate, and shift lever.
12. Raise car on hoist.
13. Disconnect fuel line at pump.
14. Remove front stone shield.
15. Disconnect speedo-cable, back-up light switch,
and clutch cable.
16. Remove drive shaft. I
17. Disconnect exhaust pipe
ar$l bell housing sup-
port.
18. Disconnect transmission support. See Figure
6A-7. 19. Remove engine mount bolts. See Figure
6A-8.
20. Attach hoist chains.
21. Lift engine and transmission assembly out of car.
Figure 6A-7 Transmission Support Bolts . Opel 1900
and Manta Series
Figure
6A-B Engine Mount Bolts - Opel 1900 and
Manta Series
Removal (GT)
The removal and installation of the 1.9 liter engine is only possible towards the floor and from below
Fig, 6A-9 Left Front Engine Suspension with Cross
Member (GT)