Opel 1973 User manual

GROUP 6
ENGINE
Section
6A
6B
6C
6D
-
6E
6F
6G
Title ‘age No.
Engine
Mechanical and Mounts
All Models
Cooling System
All Models . . . . . . . . . . . . . . . . . . . . . .
Fuel System
All Models . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Systems
All Models . . . . . . . . . . . . . . . . . . . . . . . .
Carburetor
And
Throttle Linkage . . . . . . . . . . . . . .
Emission Control
Systems - All Models . . . . .
6A- 2
6B-32
6C-36
6D-42
6E-44
6F-60
Tune-Up
All Models . . . . . . . . . . . . . . . . ..__.... 66-65
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6A- 2 1973 OPEL SERVICE MANUAL
ENGINE
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Engine Construction ..........................................................
Lubrication System ............................................................
DIAGNOSIS:
Excessive Oil Consumption ............................................
Noisy Valves and Lifters ..................................................
MAINTENANCE AND ADJUSTMENTS:
Valve Lifter Adjustment ..................................................
MAJOR REPAIR:
Engine Removal and Installation ..................................
Engine Oil Pan Removal
and Installation ..................
Manifold, Cylinder Head, Valve Train and
Lifters ................................................................................
Connecting Rod Bearings ................................................
Crankshaft Bearings and Seals ....................................
Piston, Rings and Connecting Rods ............................
Timing Chain Cover and Timing Chain ......................
Camshaft ..............................................................................
Oil Pump Cover and Gears ............................................
SPECIFICATIONS:
Bolt Torque .Specifications .................................... .
.........
General Specifications ......................................................
Engine Dimension and Fits ............................................
Page No.
6A- 2
6A- 4
6A- 6
6A- 6
6A- 7
6A- 8
6A-10
6A-12
6A-15
6A-16
6A-19
6A-23
6A-25
6A-26
6A-27
6A-28
6A-29
DESCRIPTION AND OPERATION
ENGINE CONSTRUCTION
Engine Usage
The 1.9 liter engine is standard equipment on all 1973
Opel 1900, Manta and GT models. This engine has
a compression ratio of 7.6:1 and operates on
“regular” low lead grade fuel.
Engine Construction
The cyfinderhead is made of high-grade chromium
grey cast iron. The valve guides are cast intergal with
the head. The overhead camshaft is supported in four
bearings in the cylinder head.
Location of the vzllve seats in combustion chamber
is above the center of cylinder bore. The spark plug
is positioned in the center and near the highest point
of combustion chamber. This arrangement provides
for short flame travel, uniform combustion and good
cold start prop&ties. Exhaust valves have seat in-
serts of highly heat and water resisting material. The
head surface is alumetized and so are the seats of the
inlet v&es Alumetizing makes the valve heads
non- scaling and promotes long life. All engines have
“rota-caps”.
The forged, five main bearing crankshaft has large-
diameter main and connecting rod bearing journals
with considerable overlap for vibration-free operat-
ion. T&metal bearing shells are used for main and
connecting rod bearings. The crankshaft end play is
controlled by the rear main bearing.
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ENGINE MECHANICAL AND MOUNTS 6A- 3
Figure 6A-1 Side Cross Section View of Engine
This engine has full skirt “Autothermic” type pistons
with two horizontal slots in oil control ring groove,
which partly separate head and skirt to maintain
good contact with the cylinder walls throughout the
entire temperature range.
The camshaft located in the cylinder head is an
important design feature of the new power units.
This arrangement permits an extremely rigid valve
train which accounts for precise valve timing. The
gray cast iron camshaft has induction hardened bear-
ing journals and cams. Installation of camshaft is
facilated by each diameter of the four bearings and
journals being slightly smaller than the preceding.
Camshaft end play is controlled at forward end by
the camshaft front bearing seat outer face in one
direction, and by the front bearing cover in the other
direction. A nylon bolt in camshaft forward end
serves to adjust end clearance.
The camshaft is driven by an endless Duplex roller
chain. The crankshaft double sprocket and pulley
arc held by one key. The camshaft sprocket is fixed
with a guide pin and attached with 3 bolts.
Inside the timing case, a long damper block is prov-
ided on the driving side of the chain and a shorter,
curved spring plate tensioner on the non-driving
side. Both have wear-resistant and oil-proof sny-
thetic rubber slipper pads. The self adjusting chain
tensioner located on driving side of chain at right
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6A. 4 1973 OPEL SERVICE MANUAL
hand side above crankshaft sprocket, has a plunger
head with oil- proof and wear-resistant synthetic
rubber pad, which is pressed against chain by both
spring and oil pressure.
Figure 6A-2 Sectional View. Timing System
The top end of the short, light-weight hydrauric
valve liffers is provided with a cup in which tits the
ball end of a stud engaged in an elongated hole in
rocker arm, thus maintaining transverse alignment
of the rocker arm.
The rocker xrn is a steel stamping and pivots on
a ball secured by a self-locking nut on a stud screwed
into the cylinder head. This arrangement permits
easy valve clearance adjustment. All valves have oil
seals installed between valve spring and cap.
The fuelpump is located at bottom left-hand side
of timing case and operated by, a cam integral with
distributor drive gear riveted ‘to distributor drive
shaft.
The aluminum alloy cast intake manifold with
smooth walls provide better charge of cylinders,
especially at high engine RPM. It is a four-port
manifold, i.e. there are separating walls between all
arms, one for each cylinder. An adapter for crank-
case ventilation hose leading to rocker arm cover is
arranged on front portion of intake manifold.
Hot exhaust gases are used for heating a vaporization
plate located at bend of intake manifold below carbu-
retor and communicating with its tinned underside
with the interior of the exhaust manifold to ensure
that only vaporized fuel reaches the cylinders.
LUBRICATION SYSTEM AND OIL PUMP
The engine is lubricated by a forced feed system
Figure 6A-3 Oil Pump Pressure Relief Valve
Figure 6A.4 Rear Cross Sectional View
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ENGINE MECHANICAL AND MOUNTS 6A- 5
incorporating a gear-type pump driven by the dis-
tributor shaft. The pump body forms part of the
timing case. A passage cast in cylinder block and a
suction pipe connect the pump to the screen cover
assembly in the sump of the oil pan.
The oil pump pressure relief valve is located in the
engine oil pump cover. See Figure 6A-3. The pres-
sure relief valve serves to feed surplus oil back into
the suction passage should the required oil pressure
be exceeded. The old oil pressure relief valve which
is located above the oil filter is inoperative. A heavier
spring has been installed to keep the valve seated at
all times.
The oil filter is of the full flow type. With it in paral-
lel is a by-pass system controlled by a valve in the
timing chain cover above the oil filter which ensures
oil circulation directly to lubrication points if ele-
ment becomes clogged by dirt or oil is too thick to
pass through. Only when oil flow through element is
unrestricted the by-pass valve will close and filtered
oil is fed to the engine.
Oil flow through the engine is as follows: The oil
pump draws oil from the sump through the screen
and pumps it through drilled passages in timing case
to the full flow filter. From there it passes to the
cylinder block main oil gallery with a branch in tim-
ing case to no. 1 camshaft bearing. Drilled passages
lead from the oil gallery to crankshaft main bearings
and in the crankshaft from main bearings to connect-
ing rod bearings. The camshaft front journal has a
crescent shaped groove which controls the oil supply
to cylinder head oil gallery. The cylinder head oil
gallery delivers oil under pressure to all valve lifters,
to Nos. 2, 3 and 4 camshaft bearings, and to rocker
arm seats. An additionally drilled passage connects
the valve lifter circular groove with circular groove
of rocker arm stud from where the oil is directed
upwards through a drilled passage to the rocker arm
seat. The cams are lubricated by oil under pressure.
Surplus oil collects at end of cylinder head and re-
turns through a passage to the crankcase. A cali-
brated squirt hole in connecting rod big end bearing
sprays oil against right-hand side of cylinder wall:
Additional cylinder wall and piston pin lubrication
is through oil splash from crankshaft. A jet in timing
case projects oil against oil pump drive, and the tim-
ing chain receives lubrication from above the chain
tensioner.
Figure 6A-5 Engine Lubrication System
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6A. 6 1973 OPEL SERVICE MANUAL
DIAGNOSIS
EXCESSIVE OIL CONSUMPTION
Condition Correction
External Oil Leaks at: Tighten attaching bolts. If leaks
Rocker Arm Covers persist, remove cover (or pan),
Crankcase Front Cover check sealing surfaces for burrs
Oil Pan and Gasket or scoring, replace gasket, and
seal bolts with silastic sealer or
equivalent. Make sure oil level
,is not overfull.
Improper Reading of Dip- Car may not be level when taking r
Stick InsuffIcient oil “drain-back” time
after stopping engine (three
minutes must be allowed). Dip-
stick may not be completely pushed
down against stop. Dipstick may
be bent.
Oil Viscosity Too Light Use recommended SAE viscosity for
prevailing temperatures.
Continuous High-Speed At speeds above 60 mph, increased
Driving sumption can be expected with any
Inform customer of this fact.
High-Speed Driving When principal use of automobile i
Following Normal Slow city driving, crankcase dilution f
Speed City Driving condensation occurs. High speed a
temperatures will remove water,
resulting in what appears to be
rapid lowering of oil level.
Inform customer of this fact.
Piston Rings Not Allow engine to accumulate at leas
“Broken In” 4,OCO miles before attempting any
engine disassembly to correct for
oil consumption.
NOISY VALVES AND LIFTERS If the preceding check indicates valve mechanism is
abnormally noisy, remove the rocker arm cover so
that the various conditions that cause noise may be
The noise level of the valve mechanism cannot be checked. A piece of heater hose of convenient length
properly judged where the engine is below operating may be used to pick out the particular valves or valve
temperature when the hood is raised, or when the linkages
thit are causing abnormal noise. With the
valve rocker arm covers are removed. engine running at a speed where the noise is pro-
nounced; hold the end of hose to an ear and hold
Before attempting to judge valve noise level, the en- other end about
l/2 inch from point of contact be-
gine must be thoroughly warmed up (at least 20 tween rocker arm and valve stem. Mark or record the
minutes of operation at 1200 to 1500 RPM) to stabil- noisy valves for investigation of following causes:
ize oil and coolant temperatures and bring all engine
parts to a normal state of expansion. When the en- 1. Sticking, Warped, or Eccentric Valves, Worn
gine is warmed up, listen for engine noise while sit- Guides Sticking valves will cause irregular engine
ting in the driver’s seat with the hood closed. Run the operation or missing on a low speed pull and will
engine at idle and at various higher speeds. usually cause intermittent noise.
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ENGINE MECHANICAL AND MOUNTS 6A- 7
Pour penetrating oil over the valve spring cap and engine off. It makes no difference whether the engine
allow it to drain down the valve stem. Apply pressure is cold or is at operating temperature. Set piston of
to the one side of the valve spring and then the other, the respective cylinder to upper top center on the
and then rotate the valve spring about l/2 turn. If firing stroke. This can be accomplished by removing
these operations affect the valve noise, it may be the distributor cap and observing the rotor. Check
assumed that valves should be reconditioned. position of the rotor and follow spark path for the
2. Worn or Scored Parts in the Valve Train Inspect
rotor tip through the distributor cap, high tension
rocker arms, push rod ends for scoring. Check push wire to spark plug. This determines which cylinder
rods for bends, valve lifters, and camshaft surfaces is at upper top center on the firing stroke. Adjust the
for scoring. Replace faulty parts. hydraulic lifters of the two valves for that cylinder at
this time. When they are adjusted, turn engine so
MAINTENANCE AND ADJUSTMENTS that another.cylinder is at upper top center on the
firing stroke and adjust the two valve lifters for that
VALVE LIFTER ADJUSTMENT
cylinder. Repeat process until all valves are adjusted.
See Figure 6A-6 for correct rotor position for each
Perform hydraulic valve lifter adjustment with the cylinder.
CORRECT ROTOR POSITION TO ADJUST CORRECT ROTOR POSITION TO ADJUST
VALVES ON CYLINDER NO. 1 VALVES ON CYLINDER NO. II
CORRECT ROTOR POSITION TO ADJUST CORRECT ROTOR POSITION TO ADJUST
VALVES ON CYLINDER NO. Ill VALVES ON CYLINDER NO. ,V
W-6
Figure 6A-6 Rotor Positions for Valve Lifter Adjustment
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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)
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ENGINE MECHANICAL AND MOUNTS 6A- 9
The engine does not rest on the front suspension
cross member as in the Opel 1900 and Manta but on
a separate cross member. On removal and installa-
tion of the engine the front suspension cross member
need not be detached.
Fig. 6A-10 Right Front Engine Suspension with Cross
Member (GT)
1. Disconnect battery negative cable,
2. Remove air cleaner.
3. Drain radiator coolant by disconnecting lower
radiator hose. Disconnect upper radiator hose. See
Figure 6A-11. Radiator need not be disconnected.
4. Disconnect all electrical connections:
a. Coil wire to distributor.
b. Wires from alternator. Remove unit and bracket.
c. Battery positive cable at starter switch.
d. Oil pressure switch wires at cylinder block.
e. Wires from starter solenoid.
5. Remove vacuum hoses at tee mounted to intake
manifold. Remove tee from manifold to avoid inter-
ference during engine lowering.
6. Remove throttle linkage and carburetor.
7. Disconnect heater hoses.
8. Disconnect water valve bracket to manifold,
9. Remove gear shift lever.
10. Using suitable equipment lift up engine so that
front engine mounts are somewhat relieved.
Figure 6A.1 1 Radiator Hose Clamp Location
11. Raise vehicle, both front and rear end. A two post
axle type hoist IS recommended for this operation.
12. Disconnect fuel line at fuel pump and plug. Be
sure fuel line is disconnected from any engine and
transmission clips.
13. Disconnect speedometer cable from transmis-
sion.
14. Disconnect clutch cable.
15. Disconnect drive shaft at rear universal joint and
remove.
16. Disconnect exhaust at manifold.
17. Remove tailpipe and mufIler hangers.
18. Remove ground strap from engine to side rail.
19. Detach transmission cross member from trans-
mission and frame. See Figure 6A-12.
20. Detach engine cross member from engine and
frame.
21. Carefully lower engine and transmission and
remove from underneath vehicle.
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6A- 10 1973 OPEL SERVICE MANUAL
Fig. 6A.12 Transmission Cross Member
Installation (Opel 1900 and Manta)
1. Lower engine and transmissior assembly into car.
2. Install components as remov&d in steps .1 through
19 above.
Installation (GT)
1. Install bell housing, transmission and starter.
2. Using suitable equipment raise assembly into vehi-
cle.
3. Install components as removed in steps 1 thru 21.
ENGINE OIL PAN REMOVAL AND INSTALLATION
Removal (Opel 1900 and Manta)
To remove the engine oil pan, a device similar to the
one illustrated in Figure 6A-14 can be made and used
to support the front of the engine. This particular
device was made up using hardwood, bolts, and
chain.
1. Assemble chains to engine.
Figure 6A-14 Engine Support Tool - Opel 1900 and Manta.
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ENGINE MECHANICAL AND MOUNTS 6A- 11
a. Attach left chain to alternator support rear bolt.
b. Bolt right chain to existing threaded hole at lower
right front of engine.
2. Assemble loose ends of chain to support device J-
bolts and adjust to remove engine weight from motor
mounts.
3. Remove the two motor mount bracket to motor
mount retaining nuts.
4. Remove the two front suspension to frame rail bolt
retaining nuts.
5. Remove nut and bolt at lower end of steering shaft
U-joint.
6. With a floor jack under the center of the front
suspension cross member, raise car high enough for
wheels and suspension assembly to be rolled from
under car.
7. Position jack stands under both front jack brackets
on underbody to support car in this position.
8. Remove both front cross member support to frame
attaching bolts.
9. Remove brake pipe to brake hose retaining clips
at frame rails and disconnect brake hose from brake
pipes. Use an absorbent material or suitable con-
tainer for the brake fluid that will drain out.
10. Lower the front suspension assembly and remove
from under car.
11. Drain engine oil and remove oil pan and gasket.
Installation (Opel 1900 and Manta)
1. Apply a light bead of sealer to the clean sealing
surfaces of the oil pan and affix a new gasket.
2. Bolt oil pan and gasket assembly to engine block.
3. Roll front suspension and floor jack under car and
raise into position careful to pilot the cross member
to frame rail attaching bolts and steering shaft to
their respective locations.
4. Install cross member’support to frame attaching
bolts and torque to 22 lb.ft.
5. Connect brake hose to brake pipes and install
retaining clips.
6. Bleed front brake system. Maintain brake fluid
1Wd.
7. Remove jack stands and lower car.
8. Install suspension to frame rail bolt retaining nuts.
9. Release and remove engine supporting device.
10. Install motor mount bracket to motor mount
retaining nuts.
11. Install steering shaft U-joint lower bolt and nut.
12. Replace engine oil.
Removal (GT Series)
1. Support engine in vehicle using Tool J-23375. See
Figure 6A- 15.
Figure 6A-15 Engine Holding Fixture
Install tool by removing upper engine mount nut and
installing fixture. Replace nut and tighten. The en-
gine will now be supported by the tool, between the
frame rails. The front suspension need not be
removed on GT Models.
2. Drain oil.
3. Remove oil pan bolts and remove oil.
Installation (GT Series)
1. Replace oil pan and bolts.
2. Remove engine holding fixture and replace engine
mounts.
3. Replace engine oil.
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6A- 12 1973 OPEL SERVICE MANUAL
INTAKE AND EXHAUST MANIFOLD REMOVAL
AND
INSTALLATION
Removal
1. Disconnect battery.
2. Remove air cleaner.
3. Disconnect throttle linkage at carburetor.
4. Disconnect vacuum advance line at carburetor.
5. Remove fuel line at carburetor inlet.
6. Remove positive crankcase ventilation hose at
rocker arm cover.
7. Disconnect E.G.R. lines from carburetor and in-
take manifold.
8. Disconnect exhaust pipe.
9. Remove six bolts attaching manifold assembly to
cylinder head and remove manifold and carburetor
as an assembly. Discard manifold gasket.
To separate intake and exhaust, manifold, remove
carburetor and four bolts using Tool J-23016, attach-
ing intake manifold to exhaust manifold. Always in-
stall a new manifold intermediate gasket when the
manifolds are separated.
Installation
1. Install new manifold gasket and place manifold in
position.
2. Install manifold bolts. New manifold to cylinder
head gasket must be installed whenever a manifold
is removed.
3. When installing the manifold, start with the No.
1 and No. 2 bolts. See Figure 6A-16. Gradually
tighten both bolts until snug. Then continue with the
rest of the bolts in the sequence illustrated in Figure
6A-16. Torque bolts to 33 lb. ft.
Figure 6A-16 Manifold Bolt Tightening Sequence
4. Connect parts removed in Steps 1 thru 8 above.
CYLINDER HEAD REMOVAL AND INSTALLATION
Removal
1. Drain coolant from radiator and block. Loosen
drain plug on right side of engine to avoid coolant
entering into cylmder bores. Drain plug is located on
the right rear of cylinder block above oil pressure
switch.
2. Remove hoses from thermostat housing. Collect
coolant as it contains anti-freeze.
3. Remove 6 intake and exhaust manifold attaching
bolts and swing assembly aside.
4. Remove spark plug wires from plugs.
5. Remove bracket bolt holding spark plug wires
away from cylinder head.
6. Remove rocker arm cover.
7. Remove 10 cylinder head bolts using 12 MM ser-
rated drive J-22915, and 2 cylinder head to timing
chain cover bolts with a 6MM hex head wrench. See
Figure 6A- 17.
Figure 6A-17 Serrated Bits
8. Remove three bolts attaching plate to front of
cylinder head.
9. Remove plastic screw from end of camshaft.
10. Remove 3 bolts attaching camshaft sprocket to
cylinder head. Slide sprocket off of camshaft and
remove head. Place head on bench supported at each
end by a block of wood to prevent damage to valves.
Installation
1. Install in reverse procedure to removal, paying
particular attention to the following:
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RECESSES VERTICAL FOR
REMOVAL OF LEFT ROW OF
CYLINDER HEAD BOLTS 6A-16
Figure 6A-18 Recesses in Camshaft
2. Clean piston tops and combustion chambers.
Thoroughly clean all gasket surfaces on the cylinder
block and cylinder head.
3. Lightly lubricate cylinder walls with engine oil.
Install coolant passage rubber gasket ring in timing
case. See Figure 6A-19.
I. TIMING CHAIN
2. CAMSHAFT SPROCKET
3. SPROCKET TIMING MARK
4. TIMING CASE
5. SUPPORT TIMING MARK
6. SUPPORT
7. CYLINDER BLOCK
6. RUBBER GASKET RING 6A-19
Figure 6A-19 Coolant Passage Rubber Gasket Ring in
Timing Case
ENGINE MECHANICAL AND MOUNTS
6A- 13
4. Apply silastic sealer or equivalent to both sides of
the cylinder head gasket where the gasket mates with
the timing chain cover, place new cylinder head gas-
ket onto cylinder block.
5. Install cylinder head. Be careful to place head
squarely over guide pins.
Rotate camshaft so that recesses are in vertical posi-
tion to allow installation of left row of bolts.
6. Install 10 head bolts. Tighten the bolts a little at
a time in the sequence shown in Figure 6A-20. Give
bolts a final torque in the same sequence. Torque to
72 lb. ft. (cylinder head cold). Use same procedure
for cylinder head to timing chain cover bolts with
final torque at 17 lb.ft. See Figure 6A-20. These
torques apply to lightly oiled threads.
Figure 6A-20 Cylinder Head Bolt Tightening
sequence
7. Slide camshaft sprocket with assembled chain onto
camshaft and guide pin and fasten with bolts. Install
nylon adjusting screw. After sprocket has been at-
tached to camshaft, recheck alignment to see that
chain has not slipped. Close front access hole.
8. Check camshaft end clearance between cover and
nylon screw with feeler gauge. Clearance should be
.004” - .008” Excess clearance can be eliminated by
carefully readjusting cover with a suitable drift.
Reconditioning Valves and Guides
1. Remove cylinder head. Place on clean surface.
Place head on bench supported at each end by a
block of wood to prevent damage to valves.
2. Using suitable spring compressor, such as J-8062,
compress valve spring and remove cap retainers. Re-
lease tool and remove spring and cap. See Figure 6A-
21.
3. Remove valves. Place valves in numerical order so
that they can be reinstalled in original location.
4. Remove all carbon from combustion chambers,
piston heads, and valves. When using scrapers or
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6A. 14 1973 OPEL SERVICE MANUAL
wire brushes for removing carbon, avoid scratching
valve seats and valve faces. A soft wire brush such as
J-8089 is suitable for this purpose.
Figure 6A-21 Removing Valve Cap Retainers
5. Clean carbon and gum deposits from valve guide
bores.
6. Inspect valve faces and seats for pits, burned spots
or other evidences of poor seating. If a valve head
must be ground until the outer edge is sharp in order
to true up the face,discard the valve because the
sharp edge will run too hot.
J-22917-1 .0030” O.S.
J-22917-2 .0059” 05.
J-22917-3 .Ol 18” OS.
Figure 6A-22 Reaming Valve Guide
CORRESPONDING VALVE STEM DIA.
SIZE IN. VALVE GUIDE
PRODUCTION .3553. .3562
.3538. .3543 .3524 .3528
PRODUCTION
AND SERVICE
.3582 .3592 .3567 .3572 .3553 .3559
.3615. .3622 .3597 .3602 .3583 .3588
.3671 .3681 .3656. .3661 .3642 .3647
6A-2:
Figure 6A-23 Valve Guides and Corresponding Valves
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ENGINE MECHANICAL AND MOUNTS 6A- 15
New inlet valves must not be refaced or lapped with
grinding compound. The correct angle for the intake
and exhaust valve head is 44 degrees.
10. Install cylinder head.
11. Adjust valve clearance. See MAINTENANCE
AND ADJUSTMENTS.
7. Inspect valve guides. Worn or pitted guides can be
reamed to accept valves with oversize stems. Over-
size valves are occasionally used in production.
Oversize valves are marked ’ 1 u “2” or “A” and are
stamped into the valve stem end and also stamped
near spark plug hole. See Figure 6A-22.
Replacing Rocker Arm Studs
1. When replacing rocker arm studs become neces-
sary, remove air cleaner, rocker arm cover and
rocker arm.
8. Reseat valve seats in cylinder head in the following
sequence:
Intake
NOTE: The rocker arm studs are screwed into the
cylinder head. A tapered part of the stem serves to
a void stud loosening.
With 45 degrees cutter, remove burnt structure until
a metallic bright seat is obtained. Lightly coat valve
head with red lead, insert it into guide and turn it
under light pressure several times back and forth.
Thereby a contact pattern is obtained and the seat
width can be measured. If valve does not seat per-
fectly all around, lightly recut valve seat to the estab-
lished seat width of ,049” - .059” with 30 degrees
correction cutter.
Exhaust
The directions for reconditioning intake valve seats
apply in principle also to exhaust valve seat recondi-
tioning with the exception that the valve seat width
should be .063-,073 in. and different cutters are em-
ployed.
NOTE: : OTse new valve seals whenever
valves are reconditioned.
9. Lube valves with engine oil and reinstall valves,
valve springs, caps and cap retainers using J-8062.
Install valve spring with closely wound coils toward
cylinder head. See Figure 6A-24.
2. Attach vise grip pliers to stud being removed and
remove from cylinder head.
3. Screw in new stud. Seat tapered part of stud by
striking stud end with a rubber hammer.
4. Place two turned down rocker arm nuts on
threaded part of stud.
5. Torque stud into cylinder head to 29 lb.ft.
Valve Lifter Service
The valve lifters can be removed after removing
rocker arm cover and rocker arms.
No oversize lifters have been released due to the
insignificant wear of the valve lifters and cylinder
head guides.
Amply oil respective parts and install in reverse se-
quence to removal.
Carry out hydraulic valve lifter adjustment as ou-
tlined in MAINTENANCE AND ADJUST-
MENTS.
VALVE
I SPRING
CLOSE
WOUND
COILS
TOWARD
HEAD
6A-24
Figure 6A-24 Valve Spring
CONNECTING ROD BEARINGS
A connecting rod bearing consists of two halves or
shells which are alike and interchangeable in rod and
cap. When the shells are placed in rod and cap the
ends extend slightly beyond the parting surfaces so
that when rod bolts are tightened the shells will be
clamped tightly in place to insure positive seating
and to prevent turning. Theends of shells must never
be tiled flush with parting surface of rod or cap.
If a precision type connecting rod bearing becomes
noisy or is worn so that clearance on crankpin is
excessive, a new bearing of proper size must be se-
lected and installed since no provision is made for
adjustment. Under no circumstances should the con-
necting rod or cap be filed to adjust the bearing
clearance.
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6A- 16 1973 OPEL SERVICE MANUAL
Inspection of Connecting Rod Bearings and
Crankshaft Journals
Remove oil pan.
After removal of oil pan, disconnect two connecting
rods at a time from crankshaft and inspect the bear-
ings and crankpin journals. While,tuming crankshaft
it is necessary to t&porarily reconnect the rods to
crankshaft to avoid possibility of damaging the jour-
nals through contact with loose rods.
If connecting rod bearings are chipped or scored they
should be replaced. If bearings are in good physical
condition check for proper clearance on crankpins as
described under, checking clear$nce and selecting
replacement connecting rod beartngs.
If crankpin journals are scored or ridged, the crank-
shaft must be replaced, or reground for undersize
bearings, to insure satisfactory life of connecting rod
bearings. Slight roughness may be polished out with
fine grit polishing cloth thoroughly wetted with en-
gine oil. Burrs may be honed off with a fine oil stone.
Use an outside micrometer to check crankpins for
out- of-round. If crankpins are mpre than ,002” out-
of- round, satisfactory life of new ,bearings cannot be
expected.
Checking Clearance and Selecting Replacement
Connecting Rod Bearings
Service bearings are furnished in standard size and
several undersizes. The clearance of connecting rod
(and crankshaft) bearings may be checked by use of
Plastigage, Type PG-1 (green), or equivalent, which
is soluble in oil.
1. Remove connecting rod cap with bearing shell.
Wipe off oil from bearing and crankpin journal, also
blow oil out of hole in crankshaft.
2. Place a piece of the plastic-type gauge material
Figure 6A-25 Checking Bearing Cleatance With
Plastic-Type Gauge
lengthwise along the bottom center of the lower bear-
ing shell (Figure 6A-25, view A), then install cap
with shell and tighten nuts to 36 lb. ft. Do not turn
crankshaft with gauge type material in bearing.
3. Remove bearing cap with bearing shell, the flat-
tened piece of gauge will be found adhering to either
the bearing shell or the crankpin. Do not remove it.
4. Using the scale printed on the envelope, measure
the flattened piece of gauge at its widest point. The
number within the graduation which closely corre-
sponds to the width of the gauge, indicates the bear-
ing clearance in thousandths of an inch. See Figure
6A-25, View B.
5. The desired clearance with a new bearing is
.0006”- .0025”. If bearing has been in service it is
advisable to install a new bearing if the clearance
exceeds .003”, however if bearing is in good condi-
tion and is not being checked because of bearing
noise, it is not necessary to replace the bearing.
6. After the proper size bearing has been selected,
clean off the gauge, oil thoroughly, reinstall cap with
bearing shell and tighten nuts to 36 lb. ft.
CRANKSHAFT BEARINGS AND SEALS
Replacement of Crankshaft Bearings
A crankshaft bearing consists of two halves or shells
which are identical and are interchangeable in cap
and crankcase. All crankshaft bearings except the
rear main bearing are identical. The crankshaft end
thrust is taken up the rear (No. 5) main bearing.
Figure 6A-26 Engine Crankshaft Bearings
When the shells are placed in crankcase and bearing
cap, the ends extend slightly beyond the parting sur-
faces so that when cap bolts are tightened the shells
will be clamped tightly in place to insure positive
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ENGINE MECHANICAL AND MOUNTS 6A- 17
seating and to prevent turning. The ends of she//s
must never be tiled flush with parting surface of
crankcase or bearing cap.
Crankshaft bearings are the precision type which do
not require reaming to size. Shims are not provided
for adjustment since worn bearings are readily re-
placed with new bearings of proper size. Bearings for
service replacement are furnished in standard size
and undersizes. Under no circumstances should
crankshaft bearing caps be tiIed to adjust for wear in
old bearing.
After removal of oil pan, pipe and screen assembly,
perform the following removal, inspection and in-
stallation operations on each crankshaft bearing in
turn so that the crankshaft will be well supported by
the other bearings.
If crankshaft has been removed to check straightness
the following procedure is suggested. Rest crank-
shaft on “V-blocks” at number one and number live
main bearing journals. Check indicator runout at
No. 3 main bearing journal. Total indicator reading
should not exceed .C012”.
1. Since any service condition which affects the
crankshaft bearings may also affect the connecting
rod bearings, it is advisable to inspect connecting rod
bearings first. If crankpins are worn to the extent
that crankshaft should be replaced or reground, re-
placement of crankshaft bearings only will not be
satisfactory.
If replacement of cylinder block or crankshaft is re-
quired, always check main bearing clearance with
plastic-type gauge to obtain specified limits.
2. Remove one bearing cap, then clean and inspect
lower bearing shell and the crankshaft journal. If
journal surface is scored or ridged, the crankshaft
must be replaced or reground to insure satisfactory
operation with new bearings. Slight roughness may
be polished out with tine grit polishing cloth
thoroughly wetted with engine oil, and burrs may be
honed off with a tine stone.
3. If condition of lower bearing shell and crankshaft
journal is satisfactory, check the bearing clearance
with a plastic-type gauge.
4. When checking a crankshaft bearing with plastic-
type gauging material, turn crankshaft so that oil
hole is up to avoid dripping of oil on the gauge
material. Place paper shims in lower halves of adja-
cent bearings and tighten cap bolts to take the weight
of crankshaft off the lower shell of beating being
checked.
5. If bearing clearance exceeds .C03”, it is advisable
to install a new bearing; however, if bearing is in
good condition and is not being checked because of
bearing noise, it is not necessary to replace the bear-
ing.
6. Loosen all crankshaft bearing cap bolts l/2 turn,
and remove cap of bearing to be replaced.
7. Remove upper bearing shell by inserting Bearing
Shell Remover and Installer J-8080 in oil hole in
crankshaft, then slowly turning crankshaft so that
the tool rotates the shell out of place by pushing
against the end without the tang. See Figure 6A-27.
When turning crankshaft with rear bearing cap
removed hold oil seal to prevent it from rotating out
of position in crankcase.
8. The crankshaft journal cannot be measured with
an outside micrometer when shaft is in place; how-
ever, when upper bearing shell is removed the jour-
nal may be checked for out-of-round by using a
special crankshaft caliper and inside micrometer.
Figure 6A-27 Removing and Installing Crankshaft
Bearing Upper Shell
The caliper should not be applied to journal in line
with oil hole.
If crankshaft journal is more than .M)12” out-of-
round, the crankshaft should be replaced since the
full mileage cannot be expected from bearings used
with an excessively out-of-round crankshaft.
9. Before installation of bearing shells make sure that
crankshaft journal and the bearing seats in crankcase
and cap are thoroughly cleaned.
10. Coat inside surface of upper bearing shell with
engine oil and place shell against crankshaft journal
so that tang on shell will engage notch in crankcase
when shell is rotated into place.
11. Rotate bearing shell into place as far as possible
by hand, then insert Installer J-8080 in crankshaft oil
hole and rotate crankshaft to push shell into place.
Bearing shell should move into place with very little
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6A- 18 1973 OPEL SERVICE MANUAL
pressure. If heavy pressure is required, shell was not
started squarely and will be distorted if force into
place.
12. Place lower bearing shell in bearing cap, then
check clearance with plastic-type gauge, as previ-
ously described.
13. The desired clearance with a new bearing is
.0009” to .0025”. If this clearance cannot be obtained
with a standard size bearing, insert an undersize
bearing and check again
w&h plastic-type gauge
material.
14. When the proper size bearing has been selected,
clean out all plastic gauge material, oil the lower
shell and reinstall bearing cap. Clean the bolt holes
and lube bolts, then torque cap bolts to 72 lb. ft. The
crankshaft should turn freely at flywheel rim; how-
ever, a very slight drag is permissible if an undersize
bearing is used.
15. If the thrust bearing shell is disturbed or replaced
it is necessary to line up the thrust surfaces of the
bearing shell before the cap bolts are tightened. To
do this, move the crankshaft fore and aft the limit of
its travel several times (last movement fore) with the
thrust bearing cap bolts finger tight.
16. After bearing is installed and tested, loosen all
bearing cap bolts
l/2 turn and continue with other
bearings. When bearings have been installed and
tested, tighten all bearing cap bolts to 72 lb. ft.
17. Replace rear bearing oil seals.
18. Install pipe and screen assembly and oil pan.
Installation of Rear Bearing Oil
Seals (Engine in Vehicle)
1. Remove transmission, bell housing and clutch.
Refer to appropriate section for removal procedures.
Figure 6A-28 Removing Rear Main Oil Seal
2. Remove flywheel.
3. Punch a hole into oil seal and screw in a sheet
metal screw and pull out oil seal. See Figure
6A-28.
4. To insure proper sealing, lubricate seal with a
suitable protective grease and install on taper ring
J-22928. Turn seal to ensure lip of seal is not turned
back. See Figure 6A-27.
OIL SEAL ’
6A-29
Figure
6A-29 Installing Oil Seal on Tool J-22928
5. Place tapered ring with oil seal on crankshaft
flange and move lip of seal over rear of crankshaft.
Be careful not to tilt seal.
Figure 6A-30 Installing Rear Main Bearing Oil Seal
6. Drive in oil seal using Tool J-22928-2. See Figure
6A-30.
7. Install flywheel, clutch, bell housing and transmis-
.
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ENGINE MECHANICAL AND MOUNTS 6A- 19
sion. When replacing flywheel use new bolts and
torque to 43 lb.ft.
PISTON, RINGS AND CONNECTING RODS
Removal and Disassembly of Piston
and Rod Assemblies
1. Drain oil.
2. Remove oil pan.
3. Remove cylinder head.
4. Examine the cylinder bores above the ring travel.
If bores are worn so a ridge exists, remove the ridges
with a ridge reamer to avoid damaging rings or
cracking ring lands in pistons during removal.
5. Mark the cylinder number on all pistons, connect-
ing rods and caps. Starting at the front end of the
crankcase, the cylinders are numbered l-2-3-4,
6. Remove cap and bearing shell from number 1
connecting rod.
7. Push the piston and rod assembly up and out of
top cylinder. Then reinstall cap and bearing shell on
rod.
0
-J-23436-4
J-23436-2+
J-6047
Figure
6A-3 1 Piston Pin Removal Tool Layout -1 .S
Engine
8. Remove other rod and piston assemblies in the
same manner.
9. Remove compression rings and oil rings.
10. Remove piston pin in following manner:
a. Position base support J-6047 on hydraulic press.
b. Place tool J-23436-2 in base support with large
diameter bore facing upward. See Figure 6A-31.
c. Position piston and rod assembly on tool
J-
23436-2 making certain the pin is aligned on tool.
d. Position tool J-23436-4 in opposite end of piston
pin and press pin out.
Inspection of Cylinder Bores
Inspect cylinder walls for scoring, roughness, or
ridges which indicate excessive wear. Check cylinder
bores for taper and out-of-round with an accurate
cylinder gage at top, middle and bottom ofbore, both
parallel and at right angles to the centerline of the
engine. The diameter of the cylinder bores at any
point may be measured with an inside micrometer or
by setting the cylinder gauge dial at “0” and measur-
ing across the gauge contact points with outside mi-
crometer while the gauge is at the same “0” setting.
If a cylinder bore is moderately rough or slightly
scored but is not out-of-round or tapered, it is possi-
ble to repair the bore by honing to accept a standard
service piston. If cylinder bore is very rough or
deeply scored, it may be necessary to rebore the cyl-
inder to fit an oversize piston in order to insure satis-
factory results.
If a cylinder bore is tapered
.ooO5” or more, or is
out-of-round .0005” or more, it is advisable to hone
or rebore for the smallest possible oversize piston and
rings.
Visual Inspection of Pistons, Rings, and Pins
Clean carbon from piston surfaces and under side of
piston heads. Clean carbon from ring grooves with a
suitable tool and remove any gum or varnish from
piston skirts with suitable solvent.
Carefully examine pistons for rough or scored bear-
ing surfaces, cracks in skirt, head cracked or broken
ring lands, and chipping or uneven wear which
would cause rings to seat improperly or have exces-
sive clearance in ring grooves. Damaged or faulty
pistons should be replaced.
Fitting Pistons to Cylinders
The pistons are cam ground, which means that the
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6A. 20 1973 OPEL SERVICE MANUAL
diameter at the right angle to the piston pin is greater
than the diameter parallel to the piston pin. When a
piston is checked for size, it must be measured with
micrometers applied to the skirt at ,points 90 degrees
to the piston pin. See Figure 6A-32. The piston
should be measured (for fitting p&poses) 2 l/2 in-
ches below the top of piston.
MEASURE AT
Figure 6A-32 Measuring,Piston
Inspect bearing surfaces of piston pins. Check for
wear by measuring worn and unworn surfaces with
micrometers. Rough or worn pins should be re-
placed. Check fit of piston pins in piston bosses.
Occasionally pins will be found tight due to gum or
varnish deposits. This may be corrected by removing
the deposit with a suitable solveni. If piston bosses
are worn out-of-round or oversize, the piston and pin
assembly must be replaced. Oversize pins are not
practical because the pin is a press fit in the connect-
ing rod. Piston pins must tit the piston with 0X4”
to .OCHl7” clearance.
Examine all piston rings for scores, chips or cracks.
Check compression rings for tension by comparing
with new rings. Check gap of compression rings by
placing rings in bore at bottom of ring travel. Meas-
ure gap with feeler gage. Gap should be between
,011” and .02.1”. If gaps are excessive (over .021”) it
indicates the rings have worn considerably and
should be replaced.
No attempt should be made to cut down oversize
pistons to fit cylinder bores. This practice will de-
stroy the surface treatment and affect the weight.
The sma/Jest possible oversize service pistons shouId
be used and the cylinder bores should be honed to
size for proper clearance.
1. Before installing piston, piston rings, or reboring
cylinders, observe the following:
Cylinder bores may not be the same size. Standard
replacement piston sizes are in the midpoint of the
cylinder bore size range. Therefore, it may be neces-
sary to hone cylinders for correct piston tit. Out-of-
round on cylinder bore must not exceed .ooO5”
maximum with a taper of not over .OilO5”.
Before the honing or reboring operation is started,
measure all new pistons with micrometer contacting
at points exactly 90 degrees to piston pin (Figure
6A-32) then select the smallest piston for the first
fitting. The slight variation usually found between
pistons in a set may provide for correction if the first
piston has excessive clearance.
If wear of cylinder does not exceed .005” honing is
recommended for truing the bore. If wear or out-of-
round exceeds these limits, the bore should be trued
up with a fly cutter boring bar and then finish honed.
When reboring cylinders, all crankshaft bearing caps
must be in place and tightened to proper torque to
avoid distortion ofbores in final assembly. Always be
certain the crankshaft is out of the way of the boring
cutter when boring each cylinder. When making the
final cut with boring bar, leave ,001 w on the diameter
for finish honing to give the required clearance speci-
fied.
When honing cylinders, use clean sharp stones of
proper grade for the required amount of metal to be
removed, in accordance with instructions of the hone
manufacturer. Dull or dirty stones cut unevenly and
generate excessive heat. When using coarse or
medium grade stones use care to leave sufficient
metal so that all stone marks may be removed with
the fine stones used for finishing in order to maintain
proper clearance.
When finish honing, pass the hone through the entire
length of cylinder at the rate of approximately 60
cycles per minute. This should produce the desired
45 degree cross hatch pattern on cylinder walls
which will insure maximum ring life and minimum
oil consumption.
It is of the greatest importance that refinished cylin-
der bores have not over .0005” out-of-round or ta-
pered. Each bore must be final honed to remove all
stone or cutter marks and provide a smooth surface.
During final honing, each piston must be fitted in-
dividually to the bore in which it will be installed and
should be marked to insure correct installation.
After final honing and before the piston is checked
for fit, each cylinder bore must be thoroughly
washed to remove all traces of abrasive and then
dried. The dry bore should then be brushed clean
with a power-driven iibre brush. If all traces of abra-
sive are not removed, rapid wear of new pistons and
rings will result. Fit new pistons in the following
manner:
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