1973 OPEL GT-R service

9B-28 1973 OPEL SERVICE MANUAL
Thus, from the standpoint of comfort, complete air
conditioning should control the relative humidity of
the air as well as its temperature.
By reducing the humidity, we sometimes can be just
as “cool” in a higher room temperature than other-
wise would be comfortable. Laboratory tests have
shown that the average person will feel just as cool
in a temperature of 79 degrees when the relative
humidity is down around 30 percent as he will in a
cooler temperature of 72 degrees with a high relative
humidity of 90 percent.
There are practical limits though within which wemust stay when it comes to juggling humidity. For
human comfort, we can’t go much below a relative
humidity of 30 percent because anything lower than
that would cause an unpleasant and unhealthy dry-
ness in the throat and nasal passages.
Summertime temperatures of 85 degrees sometimes
bring with them relative humidities around 75 to 80
percent. Some coastal cities have relative humidities
averaging as high as 87 percent. To gain maximum
human comfort, an air conditioning system should
cool the air down and reduce the humidity to com-
fortable limits.
The cooling job usually is done just as it is in a
refrigerator. A compressor sends refrigerant through
a chilling unit where it absorbs heat. The heat is
drawn out of the air which circulates through the
chilling unit. Along with the cooling job it does, the
evaporator unit also removes much of the moisture
from the air. Everyone is familiar with the sight of
thick frost on the freezer of a refrigerator. That frost
is simply frozen moisture that has come out of the
air.
Figure 99.22 Condensation
The evaporator unit in an air-conditioning system
does the same thing with this one exception. Becauseits temperature is above the freezing point, the mois-
ture does not collect in the form of ice or frost.
Instead, the moisture remains fluid and drips off the
chilling unit. This action is similar to what occurs on
the cool bathroom mirror when a hot shower is
turned on (Fig. 9B-22). A further advantage of airconditioning is that dust and pollen particles are
trapped by the wet surfaces of
.the evaporator core
and then drained off with the condensed moisture.
This provides very clean, pure air for breathing, and
is of great benefit to those who suffer from asthma
or ahergies such as hay fever.
Basic Refrigeration CycleLet’s review the basic refrigeration cycle. Keep this
basic cycle in mind because knowledge of the cycle,
knowledge of the particular system you are working
on and proper use of the gauges will permit quick,
accurate diagnosis of problems as they arise.
Any refrigeration system takes advantage of the
principles just described. The air conditioning sys-
tem illustrated in Fig. 9B-23 contains
five basic parts;
a compressor, a condenser, a receiver, an expansion
valve and an evaporator. Assuming R-12 as our re-
frigerant, let us follow through the refrigeration cy-
cle.Refrigerant gas under low pressure is drawn into the
compressor where it is compressed to a high pres-
sure. During compression, the refrigerant gas is
heated. When sufficient pressure is built up, the hot
gas passes into the condenser where it cools by giving
off heat to the air passing over the condenser sur-
faces.As the refrigerant gas cools, it condenses into a liquid
at high pressure and accumulates in the receiver. The
high pressure liquid refrigerant passes to the expan-
sion valve at the entrance to the evaporator. At the
valve orifice the pressure is lowered and the refriger-
ant enters the evaporator core as a low pressure liq-
uid. When the refrigerant is exposed to the lower
evaporator pressure, it begins to boil and is changed
to a vapor state. As the refrigerant passes through
the evaporator, it continues to boil by absorbing heat
from the air passing over the evaporator surfaces
until it is completely vaporized. From the evaporator
the cool low pressure refrigerant gas is drawn back
to the compressor and the cycle repeated.
Thus the air passing over the evaporator surfaces is
cooled simply by giving up heat to the refrigerant
during the boiling process.
CHEMICAL INSTABILITY AND REFRIGERATING
SYSTEM FAILURESA sealed refrigerating system is a complex physical-
chemical combination which is designed for stability

9B-30 1973 OPEL SERVICE MANUAL
refrigerant penetrates to every nook and cranny of
the unit.
Among the many desirable properties of R-12, is its
stability under operating conditions. However, while
more stable than the other refrigerants under the
same conditions, it, too, can be caused to form harm-
ful acids which will eventually fail the system.OilOil is the most complex of all of the organic chemi-
cals. Its stability in a refrigerating system is depend-
ent upon the source of crude oil and its method of
refining. A good refrigerating oil must be free of
sludge and gum-forming substances and free of
harmful impurities, such as sulphur. It must also be
stabilized to resist oxidation and must have a high
degree of resistance to carbonization.
The chemical properties of the lubricating oil form
another very important consideration in the chemi-
cal stability within the system. Like the refrigerant,
it travels to every nook and cranny of the unit.
The factory obtains the finest oils which have been
refined from the most desirable
crudes. It is reproc-
essed at the factory before it is charged into a system
or poured into a container for resale. Its
voscosityand flash point are checked and it is forced through
many sheets of filtering paper.
Even the containers in which it is poured for resale
are processed. As you recive it for field service it is
the cleanest, dry&, and purest oil that is humanly
possible to make. Leaving the container uncapped
even for a few minutes allows the oil to absorb mois-
ture from the air. Many system failures have been
caused by chemical reactions which were started by
servicemen adding contaminated oil.
Desiccants (Dehydrating Agent)Over the years the industry has spent hundreds of
thousands of dollars in finding and developing
chemical substances which are suitable for use in
refrigerating systems. An ideal desiccant must have
the following characteristics:
I. High capacity.
2. High eficiency.
3. Low tendency to powder.
4. Absorb moisture without reacting chemically with
it.5. Allow refrigerant to flow through it with mini-
mum restriction.
6. Retain moisture at high temperature.This has been a difficult combination to find. While
some desiccants excel in several of the desirable char-
acteristics, they are unsatisfactor:y in others.
Activated Silica Alumina, used in current
receiver-dehydrators, is a most satisfactory desiccant. How-
ever, its ability to retain moisture is affected by its
temperature. As the temperature increases, its ability
decreases. This means that moisture which is re-
tained at a lower temperature may be put back into
the system at a higher temperature.
MAINTAINING CHEMICAL STABILITY IN THE
REFRIGERATION SYSTEMThe metal internal parts of the refrigeration system
and the refrigerant and oil contained in the system
are designed to remain in a state of chemical stability
as long as pure R-12 plus refrigeration oil is used in
the system. However, when abnormal amounts of
foreign materials, such as dirt, air or moisture are
allowed to enter the system, the chemical stability
may be upset (Fig. 9B-24).
Figure
98.24 System Contaminants
When accelerated by heat, these contaminants may
form acids and sludge and eventually cause the
breakdown of components within the system. In ad-
dition, contaminants may affect the temperature
pressure relationship of R-12, resulting in improper
operating temperature and pressures and decreased
efficiency
OF the system.
The following general practices should be observed
to maintain chemical stability in the system:
Whenever it becomes necessary to disconnect a re-
frigerant or gauge line, it should be immediately
capped. Capping the tubing will also prevent dirt and
foreign matter from entering.
Tools should be kept clean and dry. This also in-
cludes the gauge set and replacement parts.

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.

98-34 1973 OPEL 3ERVlCE MANUAL
9B-23Figure
98.26 Compressor Front and Rear Heads
and circulated through the system via a 3/16 inch
diameter oil passage through the shaft center and
also four 5/64 inch diameter holes drilled perpen-
dicular to the shaft. The inner rotor is driven by the
shaft.TUBE
Figure
98-27 Compressor Oil Flow
4. Shaft and
Gash Plate Assembly - The shaft andwash plate assembly (see Figure 9B-162) consists of
an elliptical plate positioned obliquely to the shaft.
As the plate and shaft rotate, the surface of the plate
moves to and fro lengthwise relative to the centerline
of the shaft. This reciprocating motion is transmitted
to the pistons which contact the surface of the wash
plate. A woodruff key locks the wash plate onto theshaft. The wash plate and shaft are serviced as an
assembly. The shaft is driven by a pulley when the
magnetic clutch is energized. A needle thrust bearing
and
L mainshaft bearing support the shaft horizon-
tally and vertically.
5. Needle Thrust Bearing and Races
- Two needle
thrust bearings, each“sandwiched” between two
races are located on either side of the wash plate
hub. The front needle thrust bearing and races pro-
vide 0.010” to 0.015” clearance between the top of
the pistons and the rear side of the front suction valve
reed disc (see Figure
9B-28). The rear needle thrust
bearings and races provide 0.0005” to 0.0015” clear-
ance between the hub of the wash plate and the rear
hub of the rear cylinder. Races of various thicknesses
are provided for service replacement to achieve re-
quired clearances when rebuilding units.
6. Cylinder Assembly and service Pistons (Factory
installed pistons are ringless) -The cylinder assembly
(front cylinder and rear cylinder) is serviced only as
a matched set. Alignment of the two halves is main-
tained by two dowel (locater) pins.
The double ended pistons are made of cast alumi-
num. There are two grooves on each end of the ser-
vice piston. The outer grooves will receive a piston
ring. The inner grooves act as oil scraper grooves to
collect any excess oil. Two oil return holes are drilled

REFRIGERANT COMPONENTS ALL MODELS9s. 35
THRUST UNITSHOES ARE USED
CONTROLS PISTONTO GIVE
HEAD CLEARANCE
.0005 TO .OOlOTOTAL\CLEARANCE
THRUST UNIT CONTROLSRUNNING CLEARANCE.0005 TO .0015
9B-25Figure 98-28 Compressor Needle Thrust Bearings and
into the scraper grooves and allow oil to drain back
into the reservoir.
7. Shoe Discs
- The shoe discs are made of bronze
and act as a bearing between the ball and the wash
plate. An oil circulation hole is provided through the
center of each shoe for lubrication purposes. These
shoes are of various thicknesses and are provided in
0.0005 inch increments. Ten sizes are available for
service replacement. A basic “zero” shoe size is
available’ for preliminary gauging procedures when
rebuilding a cylinder assembly.
8. Suction Passage Cover-The suction passage cover
fits over a suction passage (see Figure 9B-30) in the
body of the cylinder assembly. Low pressure vapor
SUCTION PASSAGECOVER
TUBE9B-26
Figure 98-30 Suction Passage and Discharge Tubeflows from the suction port through the suction pas-
sage in the cylinder assembly, and into the suction
cavity of the front head.
9. Discharge Tube
- The discharge tube is used to
connect the discharge cavity in the front head with
the discharge cavity in the rear head. High pressure
vapor discharge is channeled via the tube to the dis-
charge cavity and port. A slightly modified discharge
tube is provided to be used as a service replacement
(see Figure
9B-31). The service replacement tube has
a reduced end and a built up shoulder to accomodate
an “0” ring and bushing. These added parts achieve
the necessary sealing of the high pressure vapor
within the compressor.
DISCHARGE
TUBE
oeR’NG\s~~~~~~G98.27
Figure 98.31 Service Replacement Discharge Tube
10. Pressure Relief Valve
- The purpose of the pres-
sure relief valve is to prevent the discharge pressure
from exceeding 440 psi. Opening of the pressure re-
lief valve will be accompanied by a loud popping
noise and the ejection of some refrigerant from the
valve. If the pressure relief valve is actuated due to
excessive pressures in the compressor, the cause of
the malfunction should be corrected immediately.
The pressure relief valve is located on the rear head
of the compressor.
11. Shell and Oil Drain Screw
- The shell of the
compressor contains a reservoir which furnishes a
continuous supply of oil to the moving parts of the
compressor. A
batTIe plate covers the reservoir and

98-36 1973 OPEL SERVICE MANUALSPACER
17
RETAINER
RING
c Q
CLUTCHCOIL 8HOUSINGARING TO HEADTAINER RING
SHAFT NUT
CLUTCH DRIVEN
PLATE
BEARING TO PULLEYPULLEY BEARIN
RETAINER RINGCOIL 8HOUSING
CLUTCH DRIVEPLATIRETAINER RING
AND PULLEY ASSEMBLY
Figure 98-32
Magnetic Clutch and Pulley Assemblyis tack-welded to the inside of the shell. In addition,
an oil drain screw and gasket are located on the side
of the reservoir and are provided for draining or
adding of oil to system. To add oil, compressor must
be removed from car. The necessity to add oil should
only be required when the system has ruptured vio-
lently and oil has been lost along with refrigerant.
Under controlled conditions or slow leak conditions
it is possible to loose only a small amount of oil with
the refrigerant gas. The serial number, part or model
number, and rating of the compressor is stamped on
name plates located on top of shell.
12. Magnetic Clutch and Pulley Assembly
- The
magnetic clutch and pulley assembly (see Figure 9B-
32) together transmit power from the engine crank-
shaft to the compressor. The magnetic clutch is
actuated when the air conditioning temperature
switch and the fan switch located on the evaporator
cover assembly are closed. When the switches are
closed, the coil sets up a magnetic field and attracts
the armature plate (movable element of the clutch
driven plate). The armature plate portion of the
clutch driven plate moves forward and contacts the
friction surface of the pulley assembly, thereby me-
chanically linking the compressor to the engine. The
compressor will operate continuously whenever the
air conditioner clutch compressor switch and the fan
switch are closed. When one or both of the switches
are open the armature plate will be released due to
spring tension and move away from the pulley as-
sembly. This allows the pulley to rotate without driv-
ing the shaft. It should be noted that if the air
conditioner system was in use when the engine was
turned off, the armature plate may remain in contact
with the pulley due to residual magnetism. When the
engine is started the armature plate will separate
from the pulley assembly. The coil is rated at 3.85
ohms (85 degrees F.) and will draw 3.2 amperes at
12 volts D.C.Condenser
The condenser which is made of aluminum is locatedIN:ET
DESICCANT.
RECEIVERDEHYDRATOR
ASSEMBLY
FILTER
SCREEN
Figure 98-33 Receiver Dehydrator Assembly

9B-38 1973 OPEL SERVICE MANUAL
expand and return to the original gaseous state. To
accomplish this transformation it begins to boil.
The boiling action of the refrigerant demands heat.
To satisfy the demand for heat, the air passing over
the core gives up heat to the evaporator and is subse-
quently cooled.\
DIAGNOSIS
GENERAL INFORMATIONThe following is a brief description of the type of
sympton each refrigerant component will evidence if
a malfunction occurs:
Compressor malfunction will appear in one of four
ways: noise, seizure, leakage, or low discharge pres-
sure.Resonant compressor noises are not cause for alarm;
however, irregular noise or rattles may indicate
broken parts or excessive clearances due to wear. To
check seizure, de-energize the magnetic clutch and
check to see if drive plate can be rotated. If rotation
is impossible, compressor is seized. Low discharge
pressure may be due to a faulty internal seal of the
compressor, or a restriction in the compressor.
Low discharge pressure may also be due to an insuffi-
cient refrigerant charge or a restriction elsewhere in
the system. These possibilities should be checked
prior to servicing the compressor. If the compressor
is inoperative; but, is not seized, check to see if cur-
rent is being supplied to the magnetic clutch coil
terminals.
CondenserA condenser may malfunction in two ways: it may
leak, or it may be restricted. A condenser restriction
will result in excessive compressor discharge pres-
sure. If a partial restriction is present, sometimes ice
or frost will form immediately after the restriction as
the refrigerant expands after pas?ing through the re-
striction. If air flow through the condenser or radia-
tor is blocked, high discharge pressures will result.
During normal condenser operation, the outlet pipe
will be slightly cooler than the inlet pipe.
Receiver-DehydratorA receiver-dehydrator may fail due to a restriction
inside body of unit. A restriction at the inlet to the
receiver-dehydrator will cause high head pressures.
Outlet tube restrictions will be indicated by low headpressures. Outlet tube restrictions will be indicated
by
low head pressures and little or no cooling. An
excessively cold receiver-dehydrator outlet may be
indicative of a restriction.
Expansion ValveExpansion valve failures usually will be indicated by
low suction and discharge pressures, and insuff%ient
evaporator cooling. The failure is generally due to
malfunction of the power element and subsequent
closing of the valve. A less common cause of the
above symptom is a clogged inlet screen.
EvaporatorWhen the evaporator malfunctions, the trouble will
show up as inadequate supply of cool air. A partially
plugged core due to dirt or a faulty blower will gener-
ally be the cause.
Refrigerant Line Restrictions
Rest~rictions in the refrigerant lines will be indicated
as follows:
I. Suction Line - A restricted suction line will cause
low suction pressure at the compressor, low dis-
charge pressure and little or no cooling.
2. Discharge Line -A restriction in the discharge line
generally will cause the pressure relief valve to open.
3. Liquid Line
- A liquid line restriction will be evi-
denced by low discharge and suction pressure, and
insufficient cooling.
Use of Receiver-Dehydrator Sight Glass for
DiagnosisAt temperatures higher than 70 degrees F, the sight
glass may indicate whether the refrigerant charge is
sufficient. A shortage of liquid refrigerant is in-
dicated after about
five minutes of compressor oper-
ation by the appearance of slow-moving bubbles
(vapor) or a broken column of refrigerant under the
glass. Continuous bubbles may appear in a properly
charged system on a cool day. This is a normal situa-
tion. If the sight, glass is generally clear and perform-
ance is satisfactory, occasional bubbles do not
indicate refrigerant shortage.
If the sight glass consistently shows foaming or a
broken liquid column, it should be observed after
partially blocking the air to the condenser. If under
this condition the sight glass clears and the perform-
ance is otherwise satisfactory, the charge shall be
considered adequate.