1973 OPEL GT-R fuel

6E- 561973 OPEL SERVICE MANUAL
valve stop screw. Loosen the stop screw until the
valve is completely closed. Turn the screw in l/4turn from closed position, hold, and tighten lock nut.
This is done to insure that the throttle blade will not
stick closed. See Figure
6E-30.PUMPFigure 6E-30 Adjusting Secondary Throttle Valve Gap
24. Install accelerator pump connecting rod in lower
hole of primary throttle shaft lever and cotter pin in
outboard hole at accelerator pump actuating lever
end. Paying attention to proper arrangement of cot-
ter pin and washers. See Figure
6E-2.25. With throttle plate completely closed, there
should be no clearance between the pump levei and
the pump plunger rod.
26. If a clearance is present, loosen 4 accelerator
Figure
6E-31 Accelerator Pump CoverFigure 6C32 Accelerator Pump Cover
pump cover retaining screws and allow the
dia-’phragm spring to push plunger against lever so that
a zero clearance exists. Then retighten the screws.
See Figures
6E-3 1 and 6E-32.27. Insert accelerator pump discharge nozzle so that
the bent tube end points into suction channel of the
primary barrel.
28. Fill the bowl with fuel.
29. With fuel in bowl, slowly open the throttle and
observe the accelerator pump pressure relief valve
exhaust ports and where it seats into the bowl. See
Figure
6E-33. Fuel should not be bleeding back into
the bowl from the exhaust ports or where the relief
valve seats, but a steady stream of fuel should dis-
charge from the discharge nozzle.
30. With fuel in bowl, rapidly open the throttle atid
observe the exhaust ports of the pressure relief valve.
See Figure
6E-33. Fuel should~exhaust’from the ac-
celerator pump pressure relief valve exhaust ports.
3 1. If the pressure relief valve malfunctions, remove
it and replace with a new one.
32. No float adjustment is possible, so check position
of float arm by comparing with a new float of thesame carburetor type. If float arm is bent, replace
float.

CARBURETOR AND THROTTLE LINKAGE6E- 57
ACCELERATOR PUMP
PRESSURE RELIEF
VALVE SEAT
ALVE
VENT DISCHARGE
(AIR BUBBLES FROM THIS
HOLE
IS NORMAL)
PUMP INLET
VALVE EXHAUST
PORT
--6E-33
Figure 6E-33 Carburetor Fuel Bowl
33. Install float and pivot rod making sure rod is
seated in casting.36. Install new air horn gasket so that the holes in
the gasket coincide with the screw holes in carbu-
retor housing. See Figure
6E-35.34. Install leaf spring so that spring ends rest on float
spindle. See Figure
6E-34.37. On vent valve, pay attention to cotter pin position
and arrangement of washers.
3.5. Screw in float needle valve together with copper38. Basic adjustment of idle mixture adjusting screw
seal ring
(.08 in. thick).is 5 turns open.

6E- 581973 OPEL SERVICE MANUAL
Figure 6E-34 Leaf Spring Installed
1 6E-36
Figure 6E-36 Checking Vent Valve Adjustment
39. Check compression of vent valve lower spring. It
should be compressed
l/4 inch with throttle valve
completely closed. See Figure
6E-36.40. Correct by bending valve lever.
Figure
6E-35 Installing Cover Gasket
SPECIFICATIONS
GENERAL SPECIFICATIONSCompression Ratio
........................................................................................................7.6 to 1
Fuel Required
................................(...........................................................................Low Lead
Fuel Tank Capacity (Gallons)
Opel1900andManta..
....................................................................................................11.9
GT...................................................................................................................................13.2Fuel Gauge Type
........................................................................................................Electrical
FuelPumpType
......................................................................................................Mechanical
FuelPumpDrive
..................................................................................EccentriconCamshaft
Fuel Pump Pressure at 1950 RPM
......................................................................3.1 to 3.7 psi
FuelFilter
............................................................................................................In-LineFilter
CarburetorMakeandType................................................I-Solex2BBLAutomaticChoke
AirCleanerElementType
..........................................................................FiberMesh-Paper

6F- 601973 OPEL SERVICE MANUAL
EMISSION CONTROL SYSTEMS
ALL MODELS
CONTENTS
Subject
DESCRIPTION AND OPERATION:
DescriptionandOperationofO.E.C.S.. . . . . . . . . . . . . . . . . . . . . . . .Exhaust
GasRecirculationSystem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DIAGNOSIS:
Testing Therm0 Air Cleaner Operation
. . . . . . . . . . . . . . . . . . . . . .Exhaust
GasRecirculationSystem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAINTENANCE AND ADJUSTMENTS:
Exhaust GAS Recirculation System
. . . . . . . . . . . . . . . . . . . . . . . . . . . .MAJOR REPAIR:
Removal and Replacement of O.E.C.S. Units
. . . . . . . . . .SPECIFICATIONS:
Opel Emission Control System Specifications
. . . . . . . .Page No.
6F-60
6F-62
6F-62
6F-636F-636F-636F-64
DESCRIPTION AND OPERATION
OPEL EMISSION CONTROL SYSTEM (O.E.C.S.)All 1973 cars must be capable of passing certain tests
which measure the quantity of unburned impurities
in the exhaust system. Federal law places a limit on
the hydrocarbon and carbon monoxide emissions
from the exhaust system. The purpose of this law is
to keep the atmosphere cleaner, particularly in popu-
lous areas where these impurities add to the smog
problem. Basically, excessive exhaust emissions are
caused by incomplete combustion of the air-fuel mix-
ture in the cylinders.
The basic components of the OECS on the 1.9 liter
engines are (1) leaned out carburetion, (2) heated air
(except GT), and (3) tuned spark timing.
(1) The carburetor idle system is leaned out and
special features are incorporated into the carburetors
to make possible additional idle mixture adjustments
over and above those manufactured into the carbu-
retors.
(2) The heated air package consists of a heat stove,
a corrugated paper heated air pipe, and an air cleanercontaining a temperature controlled door operated
by vacuum through a temperature sensor. See Figure6F-1.The heat stove is a sheet metal cover, shaped to and
bolted onto the exhaust manifold. Air drawn in along
Figure
6F-1 Heated Air System Installed

2. If inspection of contact points indicates excessive
burning, pitting or wear, check condenser and re-
place if necessary.
3. Inspect all connections and wires in the primary
ignition circuit. Correct any abnormal conditions
found.Carburetor1. Clean fuel strainer in fuel pump. To prevent fuel
leakage in pump, disconnect “IN” line from pump
and raise end above fuel level. The in-line fuel filter
should be replaced every 12,000 miles or every 12
months.
2. Check for freedom of choke valve operation and
clean shaft if necessary, with suitable solvent.
3. Inspect throttle cable or linkage bracket and re-
turn spring for wear. With helper depressing acceler-
ator pedal to floor, check for wide open throttle.
Adjust accelerator pedal height so wide open throttle
is obtained when pedal is within
l/2 inch from floor.
Lubricate linkage pivot points with engine oil.
Air CleanerCheck paper element every 6,000 miles and replace
every
24,ooO miles. If a vehicle is operated in dusty
territory, check condition of air cleaner element
more frequently and replace if necessary.
Fan Belt1. Inspect belt for wear, cracks or frayed points.
Replace and/or adjust as necessary. Specified ten-
sion for belt using Gauge J-23600 is 45 lbs.
Cooling System1. Inspect the radiator, water pump, cylinder head
areas and all radiator and heater hose connections
for evidence of engine coolant leaks.
2. Inspect all hoses for deterioration from gas and oil
contact. Correct as required.
Inspection should be made with engine operating at
normal temperature, cooling system completely
filled, temperature control lever fully open and nor-
mal pressure in the system. Normal pressure should
be 13.2 to 15.2 psi.
Engine Lubrication SystemInspect engine for evidence of oil leakage. Correctany abnormal condition with sealastic or new seals
and gaskets.
Battery
1. Inspect battery, battery mount and cables and
check electrolyte level. Proper level should be just
above the cell plates.
CAUTION:Do not over fill.
2. Determine the serviceability of the battery by ap-
plying the 421 Battery Test.
Positive Crankcase VentilationClean crankcase ventilator metered orifice in the in-
take manifold fitting every 6,000 miles. Also all hoses
and fittings should be inspected, cleaned and re-
placed, if necessary.
To clean, remove rubber hose from metered orifice
and apply air pressure to orifice to remove any for-
eign particles that may be trapped.
Valve Lifter AdjustmentRefer to Engine Mechanical and Mounts section for
valve lifter adjustment procedure.
Engine Tune-Up Instrument ChecksThe following instrument checks and adjustments
serve as a final check on engine condition. These
checks may discover some new problems that may
not have been obvious before. The engine is also
given its final adjustments that will assure maximum
performance, reliability, and proper emission con-
trol.
Refer to Electrical Group for checking procedures of
the following:
Cranking Voltage Check
Ignition Timing
Distributor Advance
Ignition Output
Secondary Resistance
Current Output and Voltage Setting
Idle Speed and Mixture AdjustmentsRefer to carburetor section.

Subject
Page NumbelSubjectPage Number4.Speed Manual I..
Clutch
Detent Cable Adjustment
:Differential
Directional Signal Switch
Repair Opel 1900 & Manta
Repair GT
:Disassembly of
4.Speed Manual Transmission
DistributorFunction of Valves and Hydraulic Control Units
Opel
3.Speed Automatic.................
74-21
Fuse Chart..............................lG-56
Fusible Link.............................
lA-8Specifications.
Point Replacement..
..,78-127A-
17c-9148-73E-393E-4878.23
1C-26
1 c-20
GEGas Tank See Fuel Tank
General Specifications
Engine...............................6A-28
Opel 3.Speed Automatic
.................7C-134
Transmission, Manual.,
..................78-33
Clutch...............................7A-7
Body................................ZA-4
Governor Drive Gear
Opel
3.Speed Automatic.................7C-103
Grille
Opel 1900 & Manta.....................8A-7
GT..................................8A-6 Electrically Heated Rear Window
Engine
General Description
Cooling System
Lubrication System
Trouble Diagnosis
Exhaust Manifold
Exhaust System
Removal and Installation
External Oil Leaks,
Opel 3 Speed Automatic
FFast Idle Adjustment
..................
Filter-Engine Oil
......................
Fluid Checking Procedure Transmission
Opel 3Speed Automatic.............
Frame-Opel 1900 & Manta.............
Frame
GT-Opel......................
SWVOOpel Xipeed Automatic...........
Front Suspension
Opel1900&Manta.................
GT..............................
Front Wheel Alignment................
Front Wheel Bearing Adjustment
All Series.........................
Fuel Gauge
Trouble Diagnosis
Opell$OO&Manta...............
GT............................
Fuel Pump Operation..................
Fuel System
Fuel Tank (Opel 1900 & Manta)
.......
Fuel Lines (Opel 1900 & Manta)
.......
Fuel Tank
(GT)....................
Fuel Gauge Tank Unit
(GT)...........
Fuel Lines
(GT)....................
Fuel Tank Removal and Installation....
Cleaning Tank.....................
lH-576A-268-326A-46A-66A-126D-427C-816E-51
oc-77C~Bl2B-826-77c-1003A-23A-23C-223A-4
HHazard Warning Flasher
....................lG-55
Headlamp Aiming
.........................1 F-46
Headlamp Switch
Opel 190.0 & Manta
.....................1 F-46
Headlamp Mechanism GT
..................8A-2
Heater System Opel 1900 &Manta
Trouble Diagnosis
......................9A-11
Description and Operation
................9A-10
Adjustments and Minor Service............9A-12
Removal and Installation
.................9A-12
Specifications..........................$A-16
Heater System GT
Trouble Diagnosis
......................9A-4
Description and Operation
................9A-2
Adjustments and Minor Service
............9A-4
Removal and Installation.................9A-5
Specifications..........................$A-9Horn
Operation.............................lG-54
Hydraulic Operation
Opel
3.Speed Automatic.................7C-64
IIdentification Number Vehicle...............
OA-1ldle.Adjustment
..........................6E-51
Inflation Pressures, Tires.
...................36-62
Ignition Coil
Specifications.
.........................
lC-26Identification, Engine
......................
OA-1Ignition System
Timing...............................
lC-20Instrument Panel Parts Removal