1973 OPEL 1900 bores

ENGINE MECHANICAL AND MOUNTS6A- 21
2.. Expand a telescope gage to fit the cylinder bore at
right angles to the piston pin 2-l/2” from top. See
Figure 6A-33.cylinders, the glazed cylinder walls should be slightly
dulled without increasing the bore diameter by
means of the finest grade honing stones.
TELESCOPE GAUGE1
Figure 6A-33 Checking Cylinder Bores
TELESCOPE/GAUGE
MICROMETER
Figure
6A-34 Measuring Telescope Gage3. Measure the piston to be installed. See Figure6A-32. The piston must be measured at right angles
to the piston pin
2-l/2” below the top of piston. The
piston must be between
.C008” and .0012” smaller
than the cylinder bore.
Both block and piston must be at approximately the
same temperature when measurements are made or
expansion errors will occur. A
dif.ference of 10 de-
grees F between parts is sufficient to produce a varia-
tion of .0005”.
Fitting New Piston RingsWhen new piston rings are installed without reboringNew piston rings must be checked for clearance in
piston grooves and for gap in cylinder bores; how-
ever, the flexible oil rings are not checked for gap.
The cylinder bores and piston grooves must be clean,
dry, and free of carbon and burrs.
To check the end gap of compression rings, place the
ring in the cylinder in which it will be used and
square it in the bore by tapping with the lower end
of a piston. Measure the gap with feeler gages.
Piston ring end gap should be
,014” - ,022” (top) and
,014” - ,022” (2nd) and the oil ring end gap should
be
.015” - ,055”.
If gap is less than specified, file the ends of rings
carefully with a smooth tile to obtain proper gap.
Install piston rings as follows:
1. Upper ring is chrome plated and can be installed
either way up. Number two (2) ring has to be in-
stalled with the marking “top” up. Oil ring can be
installed either way
up. See Figure 6A-35.
1. PISTON
2. NO.
I COMPRESSION RING - INSTALLED
WITH EITHER SIDE UP.
3. NO. 2 COMPRESSION RING - INSTALLED
WITH “TOP” MARKING TOWARDS THE TOP.
4. UPPER AND LOWER STEEL BAND RING
-
INSTALLED WITH EITHER SIDE UP.5. INTERMEDIATED RING
- INSTALLED WITH
EITHER SIDE UP.
6A-35
Figure 6A.35 Arrangement of Piston Rings2. Install piston rings so gaps are positioned as shown
in Figure 6A-36.

6A- 221973 OPEL SERVICE MANUALI. NO. I COMPRESSION - GAP IN FRONT
2. NO. 2 COMPRESSION - GAP IN REAR
3. UPPER STEEL BAND -
I - 2 IN.TOWARDS
THE LEFT OF INTERMEDIATE RING GAP
4. INTERMEDIATE RING - GAP IN FRONT
5. LOWER STEEL BAND -
I - 2 IN.TOWARDS
THE RIGHT OF INTERMEDIATE RING GAP.‘A” VERTICAL LINE FOR PISTON AND RINGS, FRONT
6A-36Figure 6A-36 Location of Piston Ring Gaps
With rings installed on piston, check clearance in
grooves by inserting feeler gages between each ring
and its Iower land. Any wear that occurs forms a
step at inner portion of the lower land. If the piston
grooves have worn to the extent that relatively high
steps exist on the lower lands, the piston should be
replaced since steps will interfere with the operation
of new rings causing ring clearances to become exces-
sive. Piston rings are not furnished in oversize widths
to compensate for ring groove wear.
When fitting new rings to new pistons, the side clear-
ance of the compression rings should be X024”
-
.1X34” (top) and .0013” - .OO24” (2nd), and the oil
ring clearance should be
.OO13” - .0024”.
Assembly of Piston and Connecting Rod
NOTE:Connecting rods may be out of alignment
due to shipping or
hand/i& Always check a new
rod before installing piston and pin.Inspect piston pin bores and piston pins for wear.
Piston pin bores and piston pins must be free of
varnish or scuffing when being measured. The piston
pin should be measured with a niicrometer and the
piston pin bore should be measured with a dial bore
gage or an inside micrometer. If clearance is in excess
of the
,001” wear limit, the piston and piston pin
assembly should be replaced.
1. Lubricate piston pin holes in piston and connect-
ing rod to facilitate installation of pin.
2. Install pin in following manner:
a. Position base support J-6047 on hydraulic press.b. Place tool J-23436-l in support J-6047 with small
diameter bore facing upward.
c. Place small end of tool J-23436-3 in bore of tool
J-23436- 1.d. Position piston, rod, and pin guide J-23436-3.
e. Line up pin on piston, and using tool J-23436-4
press pin into piston. See Figure 6A-37.
Ii-J-23436-4
J-23436-3--,J-23436-1
--cJ-6047
Figure 6A-37 Piston Pin Installation Tool Layout
- 1.9
Engine
3. Remove installer from connecting rod and piston
assembly and check piston for freedom of movement
on piston pin.
4. Make sure cylinder bores, pistons, connecting rod
bearings and crankshaft journals are absolutely
clean, then coat all bearing surfaces with engine oil.
5. Before installation of a piston and rod assembly in
its bore, position the crankpin straight down.
6. Remove connecting rod cap.
7. Make sure the gap in the oil ring rails and the gaps
of the compression rings are positioned correctly.
8. Lubricate the piston and rings and install in bore

6A- 261973 OPEL SERVICE MANUAL
rear of cylinder head. Remove camshaft toward
front, supporting camshaft with one hand through
access hole and taking care not to damage bearing
surfaces. See Figure 6A-43.12345 6
I. OLD PRESSURE
4. COVER GASKET
RELIEF
~~- \SSEMBLY5. COVER 8 VALVE
ASSEMBLYVALVE I
2. TIMING CASE
6. COVER ATTACHING
3. OIL PUMP GEARS
SCREWS
123” 45Figure 6A-44 Oil Pump Components
1.CAMSHAFT
2. FRONT ACCESS HOLE
3. LATERAL ACCESS HOLE
4. CYLINDER HEAD
5. REAR ACCESS HOLEISA-43
Figure 6A-43 Removing Camshaft
Installation
1. Liberally lubricate camshaft journals and install
camshaft from front into cylinder head. Support
shaft through access hole in left side of head to pre-
vent damaging bearings.
2. Reinstall valve lifters, rocker arms and self- lock-
ing rocker arm nuts.
3. Install rear and side access plates.
4. Reinstall cylinder head.
OIL PUMP COVER AND GEARSRemoval and Installation of Oil Pump
Cover and Gears
1. Remove screws attaching oil pump cover assembly
to timing chain cover. Remove cover assembly and
slide out oil pump gears. See Figure 6A-44.
2. Wash off gears and inspect for wear, scoring, etc.
Replace any gears not found serviceable. Discard
pump covers scored by gear action. If pump housing
or distributor drive shaft bushing are worn (this is
only possible after a long service life), the timing case
together with all exchangeable pump parts have to be
discarded.In isolated cases, timing cases are installed in pro-
duction having
.008 in. oversize bores for pump gears
and shafts. Oversize bores may exist either for one or
both gears; these timing cases are identified by the
number “0.2” stamped into pump flange on left and-
/or right-hand side. Oversize replacement gears
should be selected according to Part Catalog specifi-
cations.
3. Liberally lubricate spindles and gear teeth and use
new cover gasket. Install oil pump cover.
If new gears are installed, their end clearance in a dry
pump housing should be checked with a straight
edge and a feeler gauge. The gears must not protrude
more than X04 in. over pump housing. See Figure6A-45.
FEELER
AUGESTRAIGHTIEDGE
Figure 6A-45 Checking Oil Pump Gear End Clearance

ENGINE MECHANICAL AND MOUNTS6A- 29
Cooling System - Type ,._...___..___..___........................... Liquid Cooling With Circulating Pump
Filler Cap Type
- Pressure _,._.,,._.,,...,,.........,..,.....,.,.................,,......................... 13.2-15.2 PSI
Water Temperature Control
._,..__,,._.,,__.,,...,.,.,,.,,.,,.,...............,,...,,,... Thermostat and Bypass
Thermostat Open At
._,,.,,.......,__.,.........,,...,...,,..,.,,.,,...................................................... 189 F.
Cooling System Capacity
. . . . . . . . . . . . .._...__..............,,.,,.,,..,...................................,,................6 Qts.
Fan Drive
.,,...,,,....,,.,..,..,,........,..,,..,,,.............,..,,.,..,,.................,,............... Water Pump Shaft
ENGINE DIMENSIONS AND FITS
Cylinder, Crankcase, Pistons, Cylinder Head, Valves
Cyg;te; Bore Limits for Standard Size Pistons:3.659-3.660 In.
Size 23.661-3.663 In.Size 3
3.664-3.668 In.Cylindey Bore Limits for Oversize Pistons,
.02 In.Oversm
. .._............,..,,...,................................,,.,,.,,.........................................3.679-3.681 In.
Max.PermissibleCylinderBoreOut-of-Roundness
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~.OOO5In.Max.Permissible Cylinder Bore Taper
,.., ,.,, ,.,._,__. ,_, ,.. .__... ..__. ,__. .____. ..__. .._..0005In.Piston Clearance, Nominal (on skirt bottom)
_..__,,_.,.___.__.._...........,.......................... .0014 In.No. 1 Compression Ring Side Clearance in
Piston Groove
,...,,,.,,,.,,...,__..........,,..,,...,,...,..,.,,.,,..,,..,,..,,..................,,,..,,,..., .0024-.0034 In.
No. 2 Compression Ring Side Clearance in
Piston Groove
_..,,..,,,..,,..,,..,,....,.......,...,,,.,.,,,..,..,..,,..,,..,,,..,,,.,,,..,,,...,,,..,,,,..., .0013-.OO24 In.
Oil Control Ring Side Clearance in Piston
Groove
__..__..._..,,,..,...,,,..,....,..,,..,.........,..,,...,,.,,.,,..,..,,..,,...,,...,,,..,,,..,,,...,,..... .0013-X024 In.
Piston Ring Gap:
No. 1 Compression Ring
..,,.,,,..,,,..,,..,,,.,,.,,,..,......,,.,..............,......................... .014-,022 In.
No. 2 Compression Ring
_..___..__.,,..,,..,,,..,.,,,..,,.,,....................,......................... .014-,022 In.
Oil Control Ring
,...,,...,___.___.._..................,,,..,..,,..,,.,,,..,,,.,,..,,,..,,,...,,,,..,,,...,.... ,015.,055 In.
Piston Pin in Connecting Rod
..____.___..._,,__.,,,,,..,,.,,..,.................,,............................... Press Fit
IntakeExhaust
Valve Spring Pressure
Valve Closed
_______........___..,,,,,,............1.57 In. at 93 Lbs.1.36 In. at 97
Lbs.
ValveOpen. . . . . . . . . . . . . . .1.18 In. at 182 Lbs..96 In. at 180
Lbs.
Valve Stem Diameters
Standard
Size. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..3538-.3543 In..3524-.3528 In.,003 In. Oversize
____.....__.._..,,,,,,.........3567-.3572 In..3553-.3559 In..0059 In.
Oversze .__......_______...............3597-.3602 In..3583-.3588 In.
.O 1 18 In. Oversize
_._...._._____...............3656-.3661 In..3642-.3647 In.
Valve Length, Nominal
..___.............4.843 In.4.92 In.
Valve Head Diameter
___.......____...,,,........1.574 In.1.34 In.Valve Guide Bores in Cylinder Head (Intake and Exhaust)
Standard Size
,,...,,...,,..,,..,,,..,,....................................,..,,...,,.,,,,..,,,,..,,...,,,,.., .3553-.3562 In.003 in Oversjze
.,..__,,._.,__..___....,,...,,..,,...,,,,,,.,,.,,..,................,.....,................. .3582-.3592 In.
,006 in Overslze
..,...,,..,,.......................................,.........................................3615-.3622 In.
.0118 in Oversize ,._.,,..,............,,...,,........................................,,.................... .3671-.3681 In.
Valve Stem Clearance
Intake .
.._........___..___.....,............,...,,..........................................,,...................... .OOl-.0029 In.
Exhaust
._.,,........,,...,,..,,...........,,...,................,..,,..,,................,,.....,.,........................ 0039 In.
Max. Permissible Head to Stem Runout
Intake
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..OO16In.Exhaust
.,...........,,...,...,.,,...........,,...,....,....,.,,,..,,.,,,........................................,.......... .0019 In.

FUEL SYSTEMSC- 37
must always be removed before the distributor can be
removed.
EVAPORATION CONTROL SYSTEM1. The function of the fuel evaporation control sys-
tem is to absorb the fuel vapors developing in the fuel
tank, especially when vehicle is parked, due to at-
mospheric pressure and temperature influences, and
to release these fuel vapors during vehicle operation.
2. This system utilizes the property of the activated
carbon to absorb and expel fuel vapors. The activated
carbon container is installed on the left front side of
the engine compartment. The fuel tank has a
non-vented tiller cap. Vent hoses are joined in the area of
the tank. A plastic evaporation line leads from there
along vehicle underbody to the activated carbon con-
tainer.
3. A small tube above the throttle valve body con-
nects the carburetor to the activated carbon con-
tainer. In this way, the fuel vapor collected in the
activated carbon container is fed through the carbu-
retor into the combustion chambers during engine
operation.
4. The carburetor is provided with an internal and
outside ventilation, the activated carbon container is
also connected to the outside ventilation (only effec-
tive when engine is idling). In this way, the fuel
vapors escaping to the outside during engine idle are
collected by the activated carbon container and fed
into the combustion chambers.
5. The vent lines are connected to the upper part of
the activated carbon container. Fresh air enters
through a foam rubber filter at the lower part andflows, together with the fuel vapor, to the carburetor.
Metered bores in the hose fittings of the fuel tank
control the air
- and fuel vapor flow through the
activated carbon container to the carburetor, and the
pressure release in the fuel tank and ensure complete
purging of the carbon container.
Care must be taken not to mix up lines at the ac-
tivated carbon container. See Figure
6C-2.6. The metered bores in the fuel tank fitting and an
overflow protection in the fuel tank, which prevents
a complete filling of the tank, prevents fuel flows into
the activated carbon container rendering it useless.
FUEL FILTERAn AC fuel filter type (GF 423) is being used on all
1973 Opels. A vapor return line returns vapors in the
fuel line back to the fuel tank. Proper installation of
the filter is essential. The vapor return line connector
must be on top (highest point) for proper operation.
See Figure
6C-3.1. LINE TO
CARBURETOR2. FILTER
3. LINE FROM
4. VAPOR
RETURN LINE
6C-3Figure
6C-3 Fuel Filter
MAINTENANCE AND ADJUSTMENTSFigure
6C-2 Carbon CanisterCLEANING FUEL PUMP STRAINER

CARBURETOR AND THROTTLE LINKAGE65 47
Figure 6E.3 Secondary Vacuum Diaphragm
Figure
6E-4 Automatic Choke System
Figure
6E-5 Idle Systemin a richer mixture. When the throttle valve is
opened, fuel is also drawn from the upper ports,
providing a good transfer from the idle system to the
main metering jet system. See Figure
6E-5.Main Metering Jet System
During high-speed operation, fuel is drawn from the
float chamber through the main metering jet (Figure6E-2) into the emulsion tube bore. The emulsion
tube, which is provided with transverse bores, is in-
serted in the emulsion tube bore. Vacuum in the
primary venturi (Figure 6E-2) draws fuel from the
main nozzle. As the vacuum increases, the tendency
is to draw too much fuel from the main nozzle, mak-
ing the mixture too rich. To compensate for this
tendency, the fuel level drops in the emulsion tube
bore and more emulsion tube transverse bores are
exposed. Air from the high speed air jet (Figure6E-2) enters the emulsion tube through these trans-
verse bores and mixes with the fuel. The more the
fuel level drops, the more the transfer bores are ex-
posed. This causes the air-fuel ratio to remain con-
stant over the whole engine speed range. See Figure
6E-6.Figure
6E-6 High Speed System
The secondary valve diaphragm is operated by
vacuum taken from the mixing chamber of the pri-
mary barrel on the Opel 1900 and Manta only. With
the primary throttle valve almost open and with en-
gine speed at approximately half of the maximum
engine RPM, vacuum increases to such an extent
that the secondary throttle valve starts opening from
vacuum applied in the vacuum diaphragm case act-
ing through a connecting rod and throttle valve
lever. See Figure
6E-3.
Primary to Secondary Transfer SystemIn order to have a smooth engagement of the
second-

AUTOMATIC TRANSMISSION 7C-109
Figure 7C-149
21. Using a drift on tap, press out oil pump bushing
with arbor press. Use rag or cloth to protect oil pumpface.22. Install new oil pump hub bushing with arbor
press using tool J-23130-1. See Figure
7C-149. Clean
pump body, including all holes and pockets
thoroughly. With oil pump shaft hole “A” facing
downward, scribe an aligning mark on oil pump
shaft inner diameter at the center of the oil groove
to the right of hole “A”. Scribe mark on outer edge
of bushing through the centers of the small and large
drilled holes “B”. Place bushing into oil pump shaft
with small hole up, and align scribe marks on bush-
ing with those made in oil pump shaft. Use arbor
press to drive bushing into oil pump shaft until
seated in the bore. Care must be taken so that bush-
ing is pressed in straight, using the scribe marks as
a guide until firmly seated.
23. Inspect and thoroughly clean the pressure regula-
tor and priming valve assemblies. Immerse all valves
in transmission fluid before installing in bores.
24. Install pressure regulator valve in oil pump body
bore. See Figure
7C-150.25. Install pressure regulator valve, two spring seats,
spring, boost valve and sleeve in oil pump body bore.
26. Depress pressure regulator boost valve sleeve un-
til backend lines up with pin hole and insert pin to
XWP$.27. Install priming valve assembly from front face of
pump. Priming valve retainer should be pressed in
flush with surface of oil pump body. See Figure 7C-
151.28. Inspect oil pump hub oil seal rings. Replace if
damaged or side wear is noted. See Figure
7C-152.29. Inspect reverse clutch piston for damage, Re-
place if necessary.
Figure
7C-150

7C-1201973 OPEL SERVICE MANUAL
4. Inspect the secondary valve spring for distortion
or breakage.
5. Clean in solvent, air clean, and blow out all oil
passages. Inspect all oil passages, valve bores for
nicks, burrs or varnish in governor body. Replace if
necessary.6. Install roll pin flush to
,010” below the front face.
7. Install primary valve in governor placing the small
portion of the valve in
first. Use liberal amount of
transmission fluid. There is no spring for the primary
valve.
8. Install secondary valve with small spool portion of
valve in
first.9. Install secondary valve spring.
10. Depress secondary valve spring with small screw
driver and install retainer.
Disassembly, Inspection and Reassembly of
Governor Hub1. Inspect the three oil seal rings. See Figure
7C-189.Figure 7C.189
2. Remove governor hub oil screen. Inspect screen
and clean with solvent and air dry. Replace if neces-
sary. See Figure 7C-191.
3. Install oil screen flush to governor hub.
4. Inspect governor hub splines for cracks or chipped
teeth in splines. Replace governor hub if required.Figure 7C-191
Disassembly, Inspection end Reassembly of
Extension Housing1. Inspect extension housing for damage. Replace
housing if necessary.
2. Inspect parking
paw1 and spring for damage. Re-
place if necessary.
3. If lubricant leakage was noted prior to removal ofU-Joint from extension housing, extension housing
rear seal should be replaced.
4. Use screw driver to pry out extension housing seal.
5. Inspect extension housing bushing. If worn, scored
or damaged, bushing can be removed with remover
and installer tool J-21424-9 used with driver handle
J- 8092. See Figure
7C-192.6. Clean extension housing of dirt and foreign mat-
ter. Install new extension housing bushing using
remover/installer tool J-21424-9 with driver handle
J- 8092. Bushing must be installed flush to shoulder
of exi:ension housing. See Figure 7C-192.
7. Install new extension housing seal using installer
tool
Jo-21426. See Figure 7C-193.
Disassembly, Inspection and Reassembly of Servo
Piston1. Remove servo piston apply rod
2. Holding servo piston sleeve at flat portion of sleeve
with wrench, loosen the adjusting bolt lock nut and
remove. See Figure
7C-194.