1973 OPEL 1900 ABS

REFRIGERANT COMPONENTS ALL MODELS9B- 31
When adding oil, the container should be exception-
ally clean and dry due to the fact that the refrigera-
tion oil in the container is as moisture-free as it is
possible to make it. Therefore, it will quickly absorb
any moisture with which it comes in contact. For this
same reason the oil container should not be opened
until ready for use and it should be capped immedi-
ately afte;r use.
When it is necessary to open a system, have every-
thing you will need ready and handy so that as little
time as possible will be required to perform the oper-
ation. Don’t leave the system open any longer than
is necessary.
Finally, after the operation has been completed and
the system sealed again, air and moisture should be
evacuated from the system before recharging.
THE PRIMARY CAUSES OF SYSTEM FAILURES
LeaksA shortage of refrigerant causes oil to be trapped in
the evaporator. Oil may be lost with the refrigerant
at point of leakage. Both of these can cause compres-
sor seizure.
Oil circulates in the system with the refrigerant; in
solution with the liquid and in globules with the
vapor. It leaves the compressor by the action of the
pistons and mixes with the refrigerant liquid in the
condenser. The oil then enters the evaporator with
the liquid and, with the evaporator properly flooded,
is returned to the compressor through the low pres-
sure line. Some of the oil returns as globules in the
vapor, but more important, it is swept as a liquid
along the walls of the tubing by the velocity of the
vapor. If the evaporator is starved, the oil cannot
return in sut?icient quantities to keep the compressor
properly lubricated.
High Temperature and PressureAn increase in temperature causes an increase in
pressure. This accelerates chemical instability due to
existing contaminants in the system, and initiates
chemical instability in clean systems. Other results
are brittle hoses,
“0” ring gaskets, and valve dia-
phragms with possible decomposition, broken com-
pressor discharge reeds, and seized compressor
bearings.
A fundamental law of nature accounts for the fact
that when a substance, such as a refrigerant, is in-
creased in temperature, its pressure is also increased.
Any chemical reactions caused by contaminants al-
ready in the system are greatly accelerated as the
temperature increases. A 15 degree rise in tempera-
ture doubles the chemical action. Even in a goodclean system, heat alone can start a chain of harmful
chemical reactions.
While temperature alone can cause the synthetic rub-
ber parts to become brittle and possibly to decom-
pose, the increased pressure can cause them to
rupture or blow.
As the temperature and pressure increases the stress
and strain on the compressor discharge reeds also
increases. This can result in broken reeds. Due to the
effect of the contaminants caused by high tempera-
ture and pressure, compressor bearings can be
caused to seize.
High temperature and pressure are also caused by air
in the system.
Air in the SYstemAir results from a discharged system or careless ser-
vicing procedures. This reduces system capacity and
efficiency and causes oxidation of oil into gum and
varnish.
When a leak causes the system to become dis-
charged, the resulting vacuum within the system will
cause air to be drawn in. Air in the system is a
non-condensable gas and will build up in the con-
denser as it would in an air compressor tank. The
resultant heat produced will contribute to the condi-
tions discussed previously.
Many systems are contaminated and also reduced in
capacity and efficiency by servicemen who either do
not know or are careless regarding proper servicing
procedures.
Too frequently, systems which have been open to the
atmosphere during service operations have not been
properly purged or evacuated. Air is also introduced
into the system by unpurged gauge and charging
lines. Remember that any air in the system is too
much air.
Poor ConnectionsHose clamp type fittings must be properly made.
Hoses should be installed over the sealing flanges and
with the end of the hose at the stop flange. The hose
should never extend beyond the stop flange. Locate
the clamp properly and torque as recommended. Be
especially careful that the sealing flanges are not
nicked or scored or a future leak will result.
When compression fittings are used, over tightening
can cause physical damage to the “0” ring gasket
and will result in leaks. The use of torque and back-
ing wrenches is highly recommended. When making
a connection with compression fittings, the gaskets
should always be first placed over the tube before

98-32 1973 OPEL SERVICE MANUAL
inserting it in the connection. Another precaution -inspect the fitting for burrs which can cut the
“0”ring.
Restrictions
Restrictions may be due to powdered desiccant or
dirt and foreign matter. This may result in starved
evaporator and loss of cooling, or a seized compres-
SOT.When the amount of moisture in a system sufti-
ciently exceeds the capacity of the desiccant, it can
break down the desiccant and cause it to powder.
The powder passes through the dehydrator screen
with the refrigerant liquid and is carried to the ex-
pansion valve screen. While some of it may pass
through the valve screen into the evaporator, it may
quickly build up to cause a restriction.
Due to the fact that sufftcient oil can not be returned
to the compressor, it may seize.
Dirt
Dirt, which is any foreign material, may come from
cleaner residues, cutting, machining, or preserving
oils, metal dust or chips, lint or dust, loose rust,
soldering or brazing fluxes, paint or loose oxide
scale. These can also cause seized bearings by abra-
sion or wedging, discharge and expansion valve fail-
ure, decomposition of refrigerant and oil, or
corrosion of metal parts.
CorrosionCorrosion and its by-products can restrict valve and
drier screens, rough bearing surfaces or rapid fatigu-
ing of discharge reeds. This can result in high tem-
perature and pressure, decomposition or leaks. In
any event, this means a wrecked compressor.
From this, we can see the vicious circle that can be
produced in a refrigerating system to cause its fail-
ure. Corrosion can be the indirect cause of leaks, and
leaks can be the direct cause of corrosion. We can
also see the important role we as servicemen play in
maintaining chemical stability.
The major cause of corrosion is moisture.
Moisture
Moisture is the greatest enemy of refrigerating sys-
tems. Combined with metal, it produces oxide, Iron
Hydroxide and Aluminum Hydroxide. Combined
with R-12 it produces Carbonic acid, Hydrochloric
acid, and Hydrofluoric acid. Moisture can also cause
freeze-up of expansion valve and powdered desic-
cant.Although high temperature and dirt are responsible
for many difficulties in refrigerating systems, in most
instances it is the presence of moisture in the system
that accelerates these conditions. It can be said,themfore, that moisture is the greatest enemy of all.
The acids that it produces, in combination with both
the metals and the refrigerant, cause damaging
COT-
rosion. While the corrosion may not form as rapidly
with R-12 as with some other refrigerants, the even-
tual formation is as damaging.
If the operating pressure and temperature in the
evaporator is reduced to the freezing point, moisture
in the refrigerant can collect at the orifice of the
expansion valve and freeze. This temporarily re-
stricts the flow of liquid causing erratic cooling.
As previously mentioned, moisture in excess of the
desiccant’s capacity can cause it to powder.
YOU SHOULD KNOW AND REMEMBER..That the inside of the refrigerat,ion system is com-
pletely sealed from the outside world. And if that
seal remains broken at any point
- the system will
soon be destroyed. That complete and positive seal-
ing of the entire system is vitally important and that
this sealed condition is absolutely necessary to retain
the chemicals and keep them in a pure and proper
condition.
That all parts of the refrigeration system are under
pressure at all times, whether operating or idle, and
that any leakage. points are continuously losing re-
frigerant and oil.
That the leakage of refrigerant can be so silent that
the complete charge may be lost without warning.
That refrigerant gas is heavier than air and will rap-
idly drop to the floor as it flows from a point of
leakage.
That the pressure in the system may momentarily
become as high as 400 lbs. per square inch, and that
under such pressure the molecules of refrigerant are
forced out through the smallest opening or pore.
That the compressor is continually giving up some
lubricating oil to the circulating refrigerant and de-
pends upon oil in the returning refrigerant for con-
tinuous replenishment. Any stoppage or major loss
of refrigerant will therefore be fatal to the compres-
SOT.That the extreme internal dryness of a properly proc-
essed system is a truly desert condition, with the
drying material in the receiver holding tightly on to
the tiny droplets of residual moisture.

REFRIGERANT COMPONENTS ALL MODELS
99.37
in front of the radiator so that it receives a high
volume of air flow. Air passing over the condenser
absorbs the heat from the high pressure gas and
causes the refrigerant to condense into a high pres-
sure liquid.Receiver. DehydratorThe receiver-dehydrator is located in the engine
compartment. The purpose of the receiver dehydra-
tor is two fold: the unit insures a solid column of
liquid refrigerant to the expansion valve at all times,
and also absorbs any moisture in the system that
might be present. A bag of desiccant (moisture ab-
sorbing material) is provided to absorb moisture. A
sight glass (see Figure 9B-33) permits visual check-
ing of the refrigerant flow for bubbles or foam. The
continuous appearance of bubbles or foam above an
ambient temperature of 70 degrees F. usually indi-
cates an inadequate refrigerant charge. Bubbles or
foam appearing at ambient temperatures below 70
degrees F. do not necessarily indicate an inadequate
charge and may appear even when the system is
operating properly. A filter screen in the unit pre-
vents foreign material from entering the remainder
of the system.
Expansion ValveThe expansion valve is mounted on the evaporator
core inside the passenger compartment. The function
of the expansion valve is to automatically regulate
SCREEN
lLCl98.30
Figure 98-34 Expansion Valvethe flow of refrigerant into the evaporator. The ex-
pansion valve is the dividing point in the system
between the high and low pressure liquid refrigerant.
A temperature sensing bulb is connected by a capil-
lary tube to the expansion valve (see Figure
9B-34).The temperature sensing bulb (clamped to the outlet
pipe on the evaporator) measures the temperature of
the evaporator outlet pipe and transmits the temper-
ature variations to the expansion valve (see Figure
9B-34). The capillary tube and bulb are tilled with
carbon dioxide and sealed to one side of the expan-
sion valve diaphragm.
An increase in temperature will cause the carbon
dioxide in the bulb and capillary tube to expand,
overcoming the spring pressure and pushing the dia-
phragm against the operating pins (see Figure 9B-
34). This in turn will force the valve off its seat.
When the refrigerant low pressure gas flowing
through the outlet pipe of the evaporator becomes
more than 6 degrees higher or warmer than the tem-
perature at which it originally began to vaporize or
boil, the expansion valve will autmotatically allow
more refrigerant to enter evaporator. If the tempera-
ture of the low pressure gas decreases to less than 6
degrees above the temperature at which it originally
began to vaporize or boil, the expansion valve will
automatically reduce the flow of refrigerant. Thus,
an increase or decrease in the flow of refrigerant
through the evaporator will result in an increase or
decrease in the cooling by the evaporator. The tem-
perature, humidity and volume of the air passing
over the evaporator affects the rate of absorption of
heat by the evaporator. As the ambient temperature
bulb calls for more or less refrigerant will increase or
decrease. When the air is very warm, the heat trans-
fer from the air to the refrigerant is great and a
greater quantity of refrigerant is required to maintain
the temperature at the evaporator pipe at the prede-
termined value. Conversely, cool days will result in
less heat transfer and thereby require lesser quanti-
ties of refrigerant to maintain the predetermined
temperature of the evaporator outlet pipe.
EvaporatorThe function of the evaporator is to cool and
dehumidify the air flow in the passenger compart-
ment. The evaporator assembly consists of an alumi-
num core enclosed in a reinforced plastic housing.
Two (2) water drain ports are located in the bottom
of the housing. Two refrigerant lines are connected
to the side of the evaporator core: one at the bottom
and one at the top. The expansion valve is attached
to the lower (inlet) pipe, the outlet pipe is attached
to the upper pipe. The temperature sensing bulb of
the expansion valve is clamped to the outlet pipe of
the evaporator core. The high pressure liquid refrig-
erant, after it is metered through the expansion
valve, passes into the evaporator core where it is
allowed to expand under reduced pressure. As a re-
sult of the reduced pressure the refrigerant begins to

9B-64 1973 OPEL SERVICE MANUAL
4. Using No. 21 Truarc pliers (J-5403) take out
retainer ring from hub of clutch drive plate (see Fig-
ure 9B-106). Lift our spacer.
Figure 95.106 Removing
or Installing Retainer Ring inClutch Drive Plate5. If compressor has an absorbent sleeve in the neck,
pry out the sleeve retainer and remove the sleeve.
Remove the seal seat retainer ring, using No. 21
Truarc pliers, Tool J-5403, (see Figure
9B-107).
SEAL SEATFigure 98.107 Removing or Installing Shaft Seal Seat
Retaining Ring6. Thoroughly clean the area inside the compressor
neck surrounding the shaft, the
ezxposed portion of
the seal seat and the shaft itself of any dirt or foreign
material. This is absolutely necessary to prevent any
such material from getting into
t:he compressor.
7. Remove the seal seat (see Figure 9B-108) using
Tool J-23128. Insert Tool
J-2312E; into seal seat and
tighten, using a twisting motion remove the seal seat.96-82
Figure SE-108 Removing or Installing Ceramic Shaft
Seal seat
8. Remove the seal assembly, using Tool J-9392.
Press tool downward on seal while twisting it clock-
wise to engage the tabs of the seal assembly. Gently
but firmly, pull tool straight out (see Figure
9B-109).9. Remove the seal seat
“0” ring, using Tool J-9553
(see Figure
9B-110).10. Recheck the inside of the compressor neck and
the shaft. Be sure these areas are perfectly clean
before installing new parts.
Reassembly
1. Coat the new seal seat
“0” ring with clean refrig-
eration oil and install it in its groove in the compres-
sor neck. Tool J-21508 may be used to accomplish
this. (See Figure
9B;,lll)2. Coat the
“0” ring and seal face of the new seal
assembly with clean refrigeration oil. Carefully
mount the seal assembly to Tool J-9392 by engaging
the tabs of the seal with the tangs of the tool.
3. Place seal protector, Tool J-22974, over end of
shaft and carefully slide the new seal assembly onto
the shaft. Gently twist the tool clockwise while push-
ing the seal assembly down the shaft until the seal

REFRIGERANT COMPONENTS ALL MODELS96-66Figure 98.109 Removing or Installing Shaft Seal
SEAL SEAT
-Figure 98-l 10 Removing Seal Seat O-Ring
assembly engages the flats on the shaft and is seated
in place. Disengage the tool by pressing downward
and twisting tool counterclockwise.
4. Coat ihe seal face of the new seal seat with clean
refrigeration oil. Mount the seal seat on Tool J-9393
and install it in the compressor neck, taking care not
to dislodge the seal seat
“0” ring and being sure the
seal seat makes a good seal with the “0” ring.FRONT
L’HEAD
\Figure 96-l 11 Installing Seal Seat O-Ring
5. Install the new seal seat retainer ring with its flat
side against the seal seat, using No. 21 Truarc pliers
(J-5403). Use the sleeve from
Top1 J-9393 to press in
on the seal seat retainer ring so that it snaps into its
groove. Remove seal protector
Jz22974 from the end
of the shaft.
6. Install Compressor Leak Test Fixture (J-9625)
on rear head of compressor and connect gage charg-
ing lines as shown in Figure
9B-112. Pressurize suc-
tion side of compressor with Refrigerant-12 vapor to
drum pressure. Temporarily install the shaft nut and,
with compressor horizontal and oil sump down,
ro-tate the compressor shaft in nornial direction of rota-
tion several times by hand. Leak, test the seal with a
propane torch type leak
detectot; in good condition.
Correct any leak found. Remove and discard the
shaft nut.
7. Remove any excess oil, resulting from installing
the new seal parts, from the shaft and inside the
compressor neck.8. Install the new absorbent sleeve by rolling the
material into a cylinder, overlapping the ends, and
slipping it into the compressor neck with the overlap
at the top of the compressor. Using a small screw-
driver or similar instrument, carefully spread the
sleeve so that in its final position, the ends butt
together at the top vertical centerline. Install the new
sleeve retainer so that its flange face will be against
the front end of the sleeve. Using the sleeve from
Tool J-9393, press and tap with a mallet, setting the
retainer and sleeve into place, until the outer edge of

SubjectPage Number
Subject Page Number
o,,e, 1900 & Manta .....................1H-59
GT..................................lH-63
intake Manifold, 1.9L Engine
..........:.....6A-12
R
Radiator
JRadiator All Models .,.
Radio
66-32
Joint,
Ball
adder.; ...............................3A-7
dower...............................3A-7
K
Antenna Trimmer Adjustment GT
Antenna Trimmer Adjustment
Opel 1900
& Manta
Removal and Installation Opel 1900
& Manta
Removal and Installation GT
Trouble Diagnosis GT
.,.
Trouble Diagnosis -Opel 1900 &Manta
Reverse Clutch
Rings, Piston,
1.9L Engine
Rocker Arm Assembly.
1.9L Engine..
9C-1 06
9C-1 10
Keys and Locks ..........................OA-1
L
Low Servo Cover .........................7c-100
Lubrication
Engine Oil Change Interval ................OC-7
Oil Viscosity Chart. .....................
OC-7
Fluid Capacities........................OC-5
Lubrication System, Engine .................6A-4
9C-1 11
9c-107
9c-105
9c-109
7c-103
6A-19
6A-12
s
M
Mainshaft Assembly 4.Speed
Manual Transmission ....................
78-26
Manifold
Intake ...............................
6A-12
Exhaust ..............................
6A-12
Master
Cdlinder, Brake.....................5A-2
Model
D&ignation (Body Style)
.............. OA-2
Mountings. Engine, GT ....................
28-6
Opel 1900 & Manta
.......................28-6
0
Oil Chan& Interval ........................OC-7
Oil Filter: Engine
.........................OC-7
Oil Flow Circuits, Automatic Transmission .....7C-64
Oil
Pan. Engine ..........................6A-10
Oil Pump Engine.........................
6A-26
Oil Pump Transmission ....................
7C-103
Oil Recommendations Engine. ..............
OC-7
Oil Strainer-Transmission..................7C-99
Oil Viscosity Chart ........................
OC-7
Opel Emission Control System
(OECS)
Specifications..........................6F-64
Service Procedures......................6F-63
Trouble Diagnosis ......................
6F-62
P
Parking Brake............................5C-33
Piston, Pin Rings ..........................
6A~lS
Planetary Gear Set ........................
7C-118
Power Unit Brake ........................
5A-5
Propeller Shaft ...........................
4A-2
Pump, Oil Engine........................
6A-26 Sequence for Transmission Diagnosis
..........
7C-81
Service ProceduresClutch..................7A~5
Shift Linkage Adjustments
4.Speed Manual ........................78-19
3.Speed Automatic .....................7C~93
Shock Absorber, Rear
All Series .............................
3F-51
Spark Plug Specifications ...........................
66-68
Clean &Adjust. ........................
lC-22
Installation............................lC-22
Wires................................lC~21
Specifications
Engine ................................
6A-27
Front Wheel Alignment ....................
3C~22
Speedometer Installation
Opel1900&Manta.....................1 l-68
GT..................................11-70
Spring
Rear SuspensionAll Series ..............
:............3F-52
Front Suspension
Opel 1900
& Manta ...................3A~l6
GTO Opel ..........................
3A15
Starting Motor
Description ............................
1 E-1 0
Specifications .............:............1 B-1 7
Repairs
..................:............18-13
Removal..............................1 B-l 3
Steering Columns
Service Procedures -Opel 1900 &Manta ....
3E-36
Service Procedures
- GT ...._............3E-44
Steering Gear Adjustment. .....
:............3D-27
Steering Gear Disassembly and
Redssembly.....3D-30
Steering Gear Removal and Install&ion ........
30-28
Steering Linkage ..........................
38-19
Suspension
Front................................3A-2
Rear .................................
3F-51
,