1988 BMW 3 SERIES Intake manifold

1•5
Underbonnet view (left-hand side) of a
UK model 318i (1988)
1 Radiator
2 Intake manifold
3 Idle control valve
4 Accelerator cable
5 Diagnostic/service indicator resetting
socket
6 Fuse/relay box
7 Brake hydraulic fluid reservoir
8 Airflow meter
9 Air cleaner unit
10 Radiator filler cap
11 Radiator top hose
12 Oil filter housing
Underbonnet view (right-hand side) of a
UK model 318i (1988)
1 Oil filler cap
2 Valve cover
3 Engine oil filler dipstick
4 Viscous cooling fan
5 Distributor cap cover
6 Bottom hose
7 Windscreen washer fluid reservoir
8 Ignition coil
9 Clutch hydraulic fluid reservoir
10 Battery
1
Maintenance and Servicing

2A
General
Displacement
3-series, E30 body style
316i (1988 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1596 cc (M40/4-cylinder engine)
316 (1983 to 1988) and 318i (1983 to 1987) . . . . . . . . . . . . . . . . 1766 cc (M10/4-cylinder engine)
318i (1987 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1796 cc (M40/4-cylinder engine)
320i (1987 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1990 cc (M20/6-cylinder engine)
325i (1987 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2494 cc (M20/6-cylinder engine)
5-series, E28 body style (“old-shape”)
518 (1981 to 1985) and 518i (1985 to 1988) . . . . . . . . . . . . . . . . 1766 cc (M10/4-cylinder engine)
525i (1981 to 1988) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2494 cc (M30/6-cylinder engine)
528i (1981 to 1988) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2788 cc (M30/6-cylinder engine)
535i (1985 to 1988) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3430 cc (M30/6-cylinder engine)
M535i (1985 to 1988) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3430 cc (M30/6-cylinder engine)
5-series, E34 body style (“new-shape”)
518i (1990 to 1993) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1796 cc (M40/4-cylinder engine)
520i (1988 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1990 cc (M20/6-cylinder engine)
525i (1988 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2494 cc (M20/6-cylinder engine)
530i (1988 to 1991) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2986 cc (M30/6-cylinder engine)
535i (1988 to 1993) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3430 cc (M30/6-cylinder engine)
Firing order
Four-cylinder engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3-4-2
Six-cylinder engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5-3-6-2-4
Lubrication system
Oil pressure (all engines)
At idle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 to 2.0 bars
Running (for example, at 4000 rpm) . . . . . . . . . . . . . . . . . . . . . . . . . . 4 bars or above (typically)
Oil pump rotor clearance - M40 engine
(body-to-outer rotor/outer rotor-to-inner rotor) . . . . . . . . . . . . . . . . . . . 0.12 mm to 0.20 mm
Oil pump pressure relief valve spring length - M40 engine . . . . . . . . . . 84.1 mm
Chapter 2 Part A:
In-car engine repair procedures
Camshaft - removal, inspection and refitting . . . . . . See Chapter 2B
Compression check . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 2B
Crankshaft rear oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 12
Cylinder head - dismantling and inspection . . . . . . . See Chapter 2B
Drivebelt check, adjustment and renewal . . . . . . . . See Chapter 1
Engine - removal and refitting . . . . . . . . . . . . . . . . . See Chapter 2B
Engine mountings - check and renewal . . . . . . . . . . . . . . . . . . . . . . 17
Engine oil and filter change . . . . . . . . . . . . . . . . . . . See Chapter 1
Engine overhaul - general information . . . . . . . . . . . See Chapter 2B
Exhaust manifold - removal and refitting . . . . . . . . . . . . . . . . . . . . . 6
Flywheel/driveplate - removal and refitting . . . . . . . . . . . . . . . . . . . 15
Front oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Intake manifold - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 5Oil pump - removal, inspection and refitting . . . . . . . . . . . . . . . . . . 14
Repair operations possible with the engine in the vehicle . . . . . . . . 2
Rocker arm and shaft assembly - dismantling, inspection
and reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 2B
Spark plug renewal . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Timing belt and sprockets - removal, inspection and refitting . . . . . 10
Timing belt covers - removal and refitting . . . . . . . . . . . . . . . . . . . . . 9
Timing chain and sprockets - removal, inspection and refitting . . . . 8
Timing chain covers - removal and refitting . . . . . . . . . . . . . . . . . . . 7
Top Dead Centre (TDC) for No 1 piston - locating . . . . . . . . . . . . . . 3
Valve clearance check and adjustment . . . . . . . . . . . See Chapter 1
Valve cover - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Valves - servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 2B
2A•1
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert
DIY or professional
Degrees of difficulty
Specifications Contents

Torque wrench settingsNm
Timing chain tensioner plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Timing belt tensioner bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Camshaft sprocket-to-camshaft bolt
M10 and M30 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
M20 and M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Flange to camshaft (M30 engine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Timing chain or belt covers-to-engine
M6 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
M10 (bolt size) bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Crankshaft pulley bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Crankshaft hub bolt or nut
M10 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
M20 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
M30 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 440
M40 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Cylinder head bolts*
M10 four-cylinder engine
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Stage 2 (wait 15 minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 33°
Stage 3 (engine at normal operating temperature) . . . . . . . . . . . . . Angle-tighten an additional 25°
M20 six-cylinder engine with hex-head bolts
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Stage 2 (wait 15 minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Stage 3 (engine at normal operating temperature) . . . . . . . . . . . . . Angle-tighten an additional 25°
M20 six-cylinder engine with Torx-head bolts
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 90°
Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 90°
M30 six-cylinder engine (up to and including 1987 model year)
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Stage 2 (wait 15 minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 33°
Stage 3 (engine at normal operating temperature) . . . . . . . . . . . . . Angle-tighten an additional 33°
M30 six-cylinder engine (from 1988 model year)
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Stage 2 (wait 20 minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Stage 3 (engine at normal operating temperature) . . . . . . . . . . . . . Angle-tighten an additional 35°
M40 four-cylinder engine
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 90°
Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten an additional 90°
Intake manifold-to-cylinder head bolts
M8 bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
M7 bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
M6 bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Exhaust manifold-to-cylinder head nuts
M6 nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
M7 nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Flywheel/driveplate bolts
Manual transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Intermediate shaft sprocket bolt (M20 engines) . . . . . . . . . . . . . . . . . . . 60
Sump-to-block bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 to 11
Oil pump bolts (except M40 engines) . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Oil pump sprocket bolts (M10 and M30 engines) . . . . . . . . . . . . . . . . . 10
Oil pump cover plate-to-engine front end cover (M40 engines) . . . . . . . 9
Front end cover-to-engine bolts (M20 and M40 engines)
M6 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Crankshaft rear oil seal retainer-to-block bolts
M6 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
* BMW recommend that the cylinder head bolts are renewed as a matter of course.
2A•2 In-car engine repair procedures

1 General information
This Part of Chapter 2 is devoted to in-
vehicle engine repair procedures. All
information concerning engine removal and
refitting and engine block and cylinder head
overhaul can be found in Chapter 2B.
The following repair procedures are based
on the assumption that the engine is still fitted
in the vehicle. If the engine has been removed
from the vehicle and mounted on a stand,
many of the steps outlined in this Part of
Chapter 2 will not apply.
The Specifications included in this Part of
Chapter 2 apply only to the procedures
contained in this Part. Chapter 2B contains
the Specifications necessary for cylinder head
and engine block rebuilding.
The single overhead camshaft four- and
six-cylinder engines covered in this manual
are very similar in design. Where there are
differences, they will be pointed out.
The means by which the overhead
camshaft is driven varies according to engine
type; M10 and M30 engines use a timing
chain, while M20 and M40 engines have a
timing belt.
2 Repair operations possible
with the engine in the vehicle
Many major repair operations can be
accomplished without removing the engine
from the vehicle.
Clean the engine compartment and the
exterior of the engine with some type of
degreaser before any work is done. It will
make the job easier, and help keep dirt out of
the internal areas of the engine.
Depending on the components involved, it
may be helpful to remove the bonnet to
improve access to the engine as repairs are
performed (see Chapter 11 if necessary).
Cover the wings to prevent damage to the
paint. Special pads are available, but an old
bedspread or blanket will also work.
If vacuum, exhaust, oil or coolant leaks
develop, indicating a need for gasket or seal
renewal, the repairs can generally be made
with the engine in the vehicle. The intake and
exhaust manifold gaskets, sump gasket,
crankshaft oil seals and cylinder head gasket
are all accessible with the engine in place.
Exterior components, such as the intake
and exhaust manifolds, the sump, the oil
pump, the water pump, the starter motor, the
alternator, the distributor and the fuel system
components, can be removed for repair with
the engine in place.
The cylinder head can be removed without
removing the engine, so this procedure is
covered in this Part of Chapter 2. Camshaft,
rocker arm and valve component servicing ismost easily accomplished with the cylinder
head removed; these procedures are covered
in Part B of this Chapter. Note, however, that
the camshaft on the M40 engine may be
removed with the engine in the vehicle since it
is retained by bearing caps.
In extreme cases caused by a lack of
necessary equipment, repair or renewal of
piston rings, pistons, connecting rods and
big-end bearings is possible with the engine in
the vehicle. However, this practice is not
recommended, because of the cleaning and
preparation work that must be done to the
components involved.
3 Top Dead Centre (TDC) for
No 1 piston- locating
2
Note 1:The following procedure is based on
the assumption that the distributor (if
applicable) is correctly fitted. If you are trying
to locate TDC to refit the distributor correctly,
piston position must be determined by feeling
for compression at the No 1 spark plug hole,
then aligning the ignition timing marks or
inserting the timing tool in the flywheel, as
applicable.
Note 2:The No 1 cylinder is the one closest to
the radiator.
1Top Dead Centre (TDC) is the highest point
in the cylinder that each piston reaches as it
travels up and down when the crankshaft
turns. Each piston reaches TDC on the
compression stroke and again on the exhaust
stroke, but TDC generally refers to piston
position on the compression stroke.
2Positioning the piston at TDC is an essential
part of many procedures, such as timing belt
or chain removal and distributor removal.
3Before beginning this procedure, be sure to
place the transmission in Neutral, and apply
the handbrake or chock the rear wheels. Also,
disable the ignition system by detaching the
coil wire from the centre terminal of the
distributor cap, and earthing it on the engine
block with a jumper wire. Remove the spark
plugs (see Chapter 1).
4In order to bring any piston to TDC, the
crankshaft must be turned using one of the
methods outlined below. When looking at the
front of the engine, normal crankshaft rotation
is clockwise.
(a) The preferred method is to turn the
crankshaft with a socket and ratchet
attached to the bolt threaded into the
front of the crankshaft.
(b) A remote starter switch, which may save
some time, can also be used. Follow the
instructions included with the switch.
Once the piston is close to TDC, use a
socket and ratchet as described in the
previous paragraph.
(c) If an assistant is available to turn the
ignition switch to the Start position in
short bursts, you can get the piston close
to TDC without a remote starter switch.Make sure your assistant is out of the
vehicle, away from the ignition switch,
then use a socket and ratchet as
described in (a) to complete the
procedure.
5Note the position of the terminal for the
No 1 spark plug lead on the distributor cap. If
the terminal isn’t marked, follow the plug lead
from the No 1 cylinder spark plug to the cap
(No 1 cylinder is nearest the radiator).
6Use a felt-tip pen or chalk to make a mark
directly below the No 1 terminal on the
distributor body or timing cover.
7Detach the distributor cap, and set it aside
(see Chapter 1 if necessary).
8Turn the crankshaft (see paragraph 4
above) until the timing marks (located at the
front of the engine) are aligned (see
illustration). The M40 engine does not have
any timing marks at the front of the engine,
but instead has a timing hole in the flywheel
which must be aligned with a hole in the rear
flange of the cylinder block. On this engine,
turn the crankshaft until the distributor rotor is
approaching the No 1 TDC position, then
continue to turn the crankshaft until a suitable
close-fitting drill can be inserted through the
hole in the cylinder block and into the
flywheel.
9Look at the distributor rotor - it should be
pointing directly at the mark you made on the
distributor body or timing cover.
10If the rotor is 180 degrees out, the No 1
piston is at TDC on the exhaust stroke.
11To get the piston to TDC on the
compression stroke, turn the crankshaft one
complete turn (360°) clockwise. The rotor
should now be pointing at the mark on the
distributor or timing cover. When the rotor is
pointing at the No 1 spark plug lead terminal
in the distributor cap and the ignition timing
marks are aligned, the No 1 piston is at TDC
on the compression stroke. Note:If it’s
impossible to align the ignition timing marks
when the rotor is pointing at the mark, the
timing belt or chain may have jumped the
teeth on the sprockets, or may have been
fitted incorrectly.
In-car engine repair procedures 2A•3
3.8 Align the notch in the pulley with the
notch on the timing plate, then check to
see if the distributor rotor is pointing to the
No 1 cylinder (if not, the camshaft is 180
degrees out - the crankshaft will have to
be rotated 360 degrees)
2A

12After the No 1 piston has been positioned
at TDC on the compression stroke, TDC for
any of the remaining pistons can be located
by turning the crankshaft and following the
firing order. Mark the remaining spark plug
lead terminal locations just like you did for the
No 1 terminal, then number the marks to
correspond with the cylinder numbers. As you
turn the crankshaft, the rotor will also turn.
When it’s pointing directly at one of the marks
on the distributor, the piston for that particular
cylinder is at TDC on the compression stroke.
4 Valve cover-
removal and refitting
1
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you
have the correct activation code
before disconnecting the battery.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
Removal
1Disconnect the battery negative cable.
2Detach the breather hose from the valve
cover.
3On M20 engines, unbolt and remove the
intake manifold support bracket and, if
applicable, the bracket for the engine sensors
or idle air stabiliser (it will probably be
necessary to disconnect the electrical
connectors from the sensors and stabiliser).
4On M30 engines, disconnect the electrical
connector for the airflow sensor. Unclip the
electrical harness, moving it out of the way.
5Where necessary on M30 engines, remove
the hoses and fittings from the intake air hose,
then loosen the clamp and separate the hose
from the throttle body. Unscrew the mounting
nuts for the air cleaner housing, and remove
the housing together with the air hose and
airflow sensor.
6Remove the valve cover retaining nuts and
washers (see illustrations). Where necessary,
disconnect the spark plug lead clip or coverfrom the stud(s), and set it aside. It will usually
not be necessary to disconnect the leads from
the spark plugs.
7Remove the valve cover and gasket.
Discard the old gasket. On the M40 engine,
also remove the camshaft cover (see
illustrations). If applicable, remove the semi-
circular rubber seal from the cut-out at the
front of the cylinder head.
Refitting
8Using a scraper, remove all traces of old
gasket material from the sealing surfaces of
the valve cover and cylinder head.
Caution: Be very careful not to
scratch or gouge the delicate
aluminium surfaces. Gasket
removal solvents are available at
motor factors, and may prove helpful.
After all gasket material has been
removed, the gasket surfaces can be
degreased by wiping them with a rag
dampened with a suitable solvent.
9If applicable, place a new semi-circular
rubber seal in the cut-out at the front of the
cylinder head, then apply RTV-type gasket
sealant to the joints between the seal and the
mating surface for the valve cover gasket.
Note:After the sealant is applied, you should
refit the valve cover and tighten the nuts within
ten minutes.
10Refit the camshaft cover (M40 engine), the
valve cover and a new gasket. Refit the
washers and nuts; tighten the nuts evenly and
securely. Don’t overtighten these nuts - theyshould be tight enough to prevent oil from
leaking past the gasket, but not so tight that
they warp the valve cover.
11The remainder of refitting is the reverse of
removal.
5 Intake manifold-
removal and refitting
2
Removal
1Allow the engine to cool completely, then
relieve the fuel pressure on fuel-injection
engines (see Chapter 4).
2Disconnect the battery negative cable.
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you
have the correct activation code
before disconnecting the battery.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
3Drain the engine coolant (see Chapter 1)
below the level of the intake manifold. If the
coolant is in good condition, it can be saved
and reused.
4On fuel injection engines, loosen the hose
clamp and disconnect the large air inlet hose
from the throttle body. It may also be
necessary to remove the entire air
cleaner/inlet hose assembly to provide
enough working room (see Chapter 4).
2A•4 In-car engine repair procedures
4.7b Removing the camshaft cover on the
M40 engine4.7a Removing the valve cover on the
M40 engine4.7c Removing the valve cover gasket on
the M40 engine
4.6b Valve cover bolt locations (arrowed)
on M20 six-cylinder engines4.6a Valve cover bolt locations (arrowed)
on M10 four-cylinder engines

5On carburettor engines, remove the
complete air cleaner assembly (see Chap-
ter 4).
6Disconnect the coolant hoses from the
throttle body/intake manifold as applicable.
7Disconnect the throttle cable and, if
applicable, cruise control cable (see Chap-
ter 4).
8Remove the EGR valve and line where
applicable (see Chapter 6).
9At this stage on the M40 engine, the upper
part of the intake manifold should be removed
by unscrewing the bolts and nuts. Remove
the gaskets (see illustrations).
10On fuel injection engines, disconnect the
vacuum hose from the fuel pressure regulator,
and disconnect the electrical connectors from
the fuel injectors (see Chapter 4).
11Disconnect the fuel lines from the fuel rail
or carburettor, as applicable (see Chapter 4).
12On the M40 engine, unbolt and remove
the support bracket from the bottom of the
intake manifold (see illustration).
13Disconnect all remaining hoses and wires
attached between the intake manifold/throttle
body assembly and the engine or chassis.
14Remove the bolts and/or nuts that attach
the manifold to the cylinder head (see
illustrations). Start at the ends and work
toward the middle, loosening each one a little
at a time until they can be removed by hand.
Support the manifold while removing the
fasteners so it doesn’t fall. Note: You can
remove the manifold without removing the
throttle body, injectors, vacuum/thermovalves, fuel pressure regulator or carburettor.
If you’re fitting a new manifold, transfer the
components (see Chapter 4) and lines to the
new manifold before it is fitted on the cylinder
head.
15Move the manifold up and down to break
the gasket seal, then lift it away from the head
and remove the gasket (see illustrations).
Refitting
16Remove the old gasket, then carefully
scrape all traces of sealant off the head and
the manifold mating surfaces. Be very careful
not to nick or scratch the delicate aluminium
mating surfaces. Gasket removal solvents are
available at motor factors, and may prove
helpful. Make sure the surfaces are perfectly
clean and free of dirt and oil.17Check the manifold for corrosion (at the
coolant passages), cracks, warping and other
damage. Cracks and warping normally show
up near the gasket surface, around the stud
holes. If defects are found, have the manifold
repaired (or renew it, as necessary).
18When refitting the manifold, always use a
new gasket. Where one side of the gasket has
a graphite surface, this must face the cylinder
head.
19Refit the nuts and bolts and tighten them
gradually, working from the centre out to the
ends, to the torque listed in this Chapter’s
Specifications.
20The remainder of refitting is the reverse of
removal. On the M40 engine, renew the
gaskets between the upper and lower parts of
the manifold.
In-car engine repair procedures 2A•5
5.9c . . . and gaskets5.9b . . . and remove the upper part of the
intake manifold . . .5.9a On the M40 engine, remove the nuts
and special bolts . . .
5.15b Removing the lower intake manifold
gasket (M40 engine)5.15a Removing the lower intake manifold
(M40 engine)
5.14a Remove the intake manifold nuts
with a socket, ratchet and long extension
(M20 engine)5.12 Removing the support bracket from
the bottom of the intake manifold
(M40 engine)
5.14b Removing the lower intake manifold
nuts (M40 engine)
2A

22Using a scraper, remove all traces of old
gasket material from the sealing surfaces of
the covers and engine block.
Caution: Be very careful not to
scratch or gouge the delicate
aluminium surfaces. Also, do not
damage the sump gasket, and
keep it clean. Gasket removal solvents are
available at motor factors, and may
prove helpful. After all gasket material has
been removed, the gasket surfaces
can be degreased by wiping them
with a rag dampened with a suitable
solvent.
23Support the cover on two blocks of wood,
and drive out the seals from behind with a
hammer and screwdriver. Be very careful not
to damage the seal bores in the process.
24Coat the outside diameters and lips of the
new seals with multi-purpose grease, and
drive the seals into the cover with a hammer
and a socket slightly smaller in diameter than
the outside diameter of the seal.
25Apply a film of RTV-type gasket sealant to
the surface of the sump gasket that mates
with the front cover. Apply extra beads of RTV
sealant to the edges where the gasket meets
the engine block. Note:If the sump gasket is
damaged, instead of fitting a whole new
gasket, you might try trimming the front
portion of the gasket off at the point where it
meets the engine block, then trim off the front
portion of a new sump gasket so it’s exactly
the same size. Cover the exposed inside area
of the sump with a rag, then clean all traces of
old gasket material off the area where the
gasket was removed. Attach the new gasket
piece to the sump with contact-cement-type
gasket adhesive, then apply RTV-type sealant
as described at the beginning of this
paragraph.
26Coat both sides of the new gasket with
RTV-type gasket sealant, then attach the front
cover to the front of the engine, carefully
working the seals over the crankshaft and
intermediate shaft. Refit the bolts and tighten
them evenly to the torque listed in this
Chapter’s Specifications. Work from bolt-to-
bolt in a criss-cross pattern, to be sure they’re
tightened evenly.Note 1:Tighten the front
cover-to-block bolts first, then tighten the
sump-to-cover bolts. Note 2:After applying
RTV-type sealant, reassembly must be
completed in about 10 minutes so the RTV
won’t prematurely harden.
27The remainder of refitting is the reverse of
removal.
Crankshaft front seal (M40 engines)
28Remove the timing belt and crankshaft
sprocket (see Section 10).
29Remove the Woodruff key from the
groove in the end of the crankshaft.
30Note the fitted position of the oil seal, then
prise it out from the front cover using a
screwdriver, but take care not to damage the
bore of the cover or the surface of thecrankshaft. If the seal is tight, drill two small
holes in the metal end of the seal, and use two
self-tapping screws to pull out the seal. Make
sure all remains of swarf are removed.
31Coat the outside diameter and lip of the
new seal with multi-purpose grease, then
drive it into the cover with a hammer and a
socket slightly smaller in diameter than the
outside diameter of the seal. Make sure the
seal enters squarely.
32The remainder of refitting is the reverse of
removal. Note that it is recommended that the
timing belt be renewed - see Section 10.
12 Cylinder head-
removal and refitting
5
Removal
1Relieve the fuel pressure on all fuel injection
engines (see Chapter 4).
2Disconnect the negative cable from the
battery. Where the battery is located in the
engine compartment, the battery may be
removed completely (see Chapter 5).
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you
have the correct activation code
before disconnecting the battery.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
3Remove the air cleaner assembly (see
Chapter 4).
4Disconnect the wiring from the distributor
(mark all wiring for position first, if necessary),
and the HT lead from the coil (see Chapter 5).
5Disconnect the lead from the coolant
temperature sender unit (see Chapter 3).
6Disconnect the fuel lines from the fuel rail or
carburettor as applicable (see Chapter 4).
7Drain the cooling system (see Chapter 3).
8Clearly label then disconnect all other
hoses from the throttle body, intake manifold,
carburettor and cylinder head, as applicable.
9Disconnect the throttle cable from the
throttle linkage or carburettor (see Chapter 4).
10Disconnect the exhaust manifold from the
cylinder head (see Section 6). Depending on
the engine type, It may not be necessary to
disconnect the manifold from the exhaust
pipe; however, on right-hand-drive models,
the steering column intermediate shaft may
not allow the manifold to clear the studs on
the cylinder head.
11Remove or disconnect any remaining
hoses or lines from the intake manifold,
including the ignition advance vacuum line(s),
and the coolant and heater hoses.
12On early carburettor models, disconnect
the wiring from the alternator and starter
motor.13Remove the intake manifold (see Sec-
tion 5). Do not dismantle or remove any fuel
injection system components unless it is
absolutely necessary.
14Remove the fan drivebelt and fan (see
Chapter 3).
15Remove the valve cover and gasket (see
Section 4). Remove the semi-circular rubber
seal from the front of the cylinder head, where
this is not incorporated in the valve cover
gasket.
16Set No 1 piston at Top Dead Centre on
the compression stroke (see Section 3).
17Remove the timing chain or belt (see
Section 8 or 10). Note:If you want to save
time by not removing and refitting the timing
belt or chain and re-timing the engine, you can
unfasten the camshaft sprocket and suspend
it out of the way - with the belt or chain still
attached - by a piece of rope. Be sure the
rope keeps firm tension on the belt or chain,
so it won’t become disengaged from any of
the sprockets.
18Loosen the cylinder head bolts a quarter-
turn at a time each, in the reverse of the
tightening sequence shown (see illustrations
12.30a, 12.30b, 12.30c or 12.30d). Do
notdismantle or remove the rocker arm
assembly at this time on M10, M20 and M30
engines.
19Remove the cylinder head by lifting it
straight up and off the engine block. Do not
prise between the cylinder head and the
engine block, as damage to the gasket sealing
surfaces may result. Instead, use a blunt bar
positioned in an intake port to gently prise the
head loose.
20Remove any remaining external
components from the head to allow for
thorough cleaning and inspection. See
Chapter 2B for cylinder head servicing
procedures. On the M40 engine, remove the
rubber O-ring from the groove in the top of the
oil pump/front end cover housing.
Refitting
21The mating surfaces of the cylinder head
and block must be perfectly clean when the
head is refitted.
22Use a gasket scraper to remove all traces
of carbon and old gasket material, then clean
the mating surfaces with a suitable solvent. If
there’s oil on the mating surfaces when the
head is refitted, the gasket may not seal
correctly, and leaks could develop. When
working on the block, stuff the cylinders with
clean rags to keep out debris. Use a vacuum
cleaner to remove material that falls into the
cylinders.
23Check the block and head mating
surfaces for nicks, deep scratches and other
damage. If the damage is slight, it can be
removed with a file; if it’s excessive,
machining may be the only alternative.
24Use a tap of the correct size to chase the
threads in the head bolt holes, then clean the
holes with compressed air - make sure that
In-car engine repair procedures 2A•13
2A

detach them. Pieces of masking tape with
numbers or letters written on them work well
(see illustration).
6Label and detach all coolant hoses from the
engine (see Chapter 3).
7Remove the cooling fan, shroud and
radiator (see Chapter 3). Note:On the M40
engine, it is only necessary to remove the
cooling fan and shroud; however, prevent
damage to the radiator by covering it with a
piece of wood or cardboard.
8Remove the drivebelts (see Chapter 1).
9Disconnect the fuel lines from the fuel rail
(see Chapter 4).
Warning: Fuel is extremely
flammable, so take extra
precautions when you work on
any part of the fuel system. Don’t
smoke, or allow open flames or bare light
bulbs, near the work area, and don’t work
in a garage where a natural gas-type
appliance (such as a water heater or
clothes dryer) with a pilot light is present.
If you spill any fuel on your skin, rinse it off
immediately with soap and water. When
you perform any kind of work on the fuel
system, wear safety glasses, and have a
fire extinguisher on hand.
10Disconnect the accelerator cable (see
Chapter 4) and kickdown linkage/speed
control cable (see Chapter 7B), if applicable,
from the engine.
11Where fitted, unbolt the power steering
pump (see Chapter 10). Leave the lines/hoses
attached, and make sure the pump is kept in
an upright position in the engine compartment
(use wire or rope to restrain it out of the way).
12On air-conditioned models, unbolt the
compressor (see Chapter 3) and set it aside,
or tie it up out of the way. Do not disconnect
the hoses.
13Drain the engine oil (see Chapter 1) and
remove the filter. Remove the engine splash
guard from under the engine.
14Remove the starter motor (see Chapter 5).15Remove the alternator (see Chapter 5).
This is not essential on all models, but it is a
good idea in any case to avoid accidental
damage.
16Unbolt the exhaust system from the
engine (see Chapter 4).
17If you’re working on a vehicle with an
automatic transmission, remove the torque
converter-to-driveplate fasteners (see
Chapter 7B). On the M40 engine, unbolt the
automatic transmission fluid coolant pipes
from the sump.
18Support the transmission with a jack.
Position a block of wood between them, to
prevent damage to the transmission. Special
transmission jacks with safety chains are
available - use one if possible.
19Attach an engine sling or a length of chain
to the lifting brackets on the engine. If the
brackets have been removed, the chain can
be bolted directly to the intake manifold studs,
but place a flat washer between the chain and
the nut, and tighten the nut all the way up to
the chain, to avoid the possibility of the studs
bending.
20Roll the hoist into position and connect
the sling to it. Take up the slack in the sling or
chain, but don’t lift the engine.
Warning: DO NOT place any part
of your body under the engine
when it’s supported only by a
hoist or other lifting device.
21On M10, M20 and M30 engines, remove
the transmission rear crossmember, and
slightly lower the rear of the transmission.
22Remove the transmission-to-engine block
bolts using a Torx socket. Note:The bolts
holding the bellhousing to the engine block
will require a swivel at the socket, and a very
long extension going back towards the
transmission.
23Remove the engine mounting-to-frame
bracket nuts. On the M40 engine, unbolt the
dampers from the mountings.
24Recheck to be sure nothing is still
connecting the engine to the transmission or
vehicle. Disconnect anything still remaining.
25Raise the engine slightly. Carefully work it
forwards to separate it from the transmission.
If you’re working on a vehicle with an
automatic transmission, you may find the
torque converter comes forward with theengine. If it stays with the transmission, leave
it, but you may find it easier to let it come
forward until it can be grasped easier and be
pulled from the crankshaft. Note:When
refitting the torque converter to the
transmission before the engine is refitted, be
sure to renew the transmission front pump
seal, which will probably be damaged when
the converter comes out with the engine.
Either method is acceptable, but be prepared
for some fluid to leak from the torque
converter if it comes out of the transmission. If
you’re working on a vehicle with a manual
transmission, draw the engine forwards until
the input shaft is completely disengaged from
the clutch. Slowly raise the engine out of the
engine compartment. Check carefully to make
sure everything is disconnected.
26Remove the flywheel/driveplate (and
where applicable, the engine rear plate), and
mount the engine on an engine stand (see
illustration). Do not turn the M40 engine
upside-down (see Cautionin Section 4).
Refitting
27Check the engine and transmission
mountings. If they’re worn or damaged, renew
them.
28Refit the flywheel or driveplate (see
Chapter 2A). If you’re working on a manual
transmission vehicle, refit the clutch and
pressure plate (see Chapter 7A). Now is a
good time to fit a new clutch.
29If the torque converter came out with the
engine during removal, carefully refit the
converter into the transmission before the
engine is lowered into the vehicle.
30Carefully lower the engine into the engine
compartment - make sure the engine
mountings line up.
31If you’re working on an automatic
transmission vehicle, guide the torque
converter onto the crankshaft following the
procedure outlined in Chapter 7B.
32If you’re working on a manual
transmission vehicle, apply a dab of high-
melting-point grease to the input shaft, and
guide it into the clutch and crankshaft pilot
bearing until the bellhousing is flush with the
engine block.. Do not allow the weight of the
engine to hang on the input shaft.
33Refit the transmission-to-engine bolts,
and tighten them securely.
Caution: DO NOT use the bolts to
force the transmission and
engine together.
34Refit the remaining components in the
reverse order of removal.
35Add coolant, oil, power steering and
transmission fluid as needed.
2B•6 General engine overhaul procedures
5.26 Removing the engine rear plate -
M40 engine5.5 Label each wire before unplugging the
connector
If there’s any possibility of
confusion, make a sketch of
the engine compartment and
clearly label the lines, hoses
and wires.
It may be necessary to rock
the engine slightly, or to turn
the crankshaft, to allow the
input shaft splines to mate
with the clutch plate