21 Steering box (5-Series)-
removal and refitting
4
Removal
Note:If you find that the steering box is
defective, it is not recommended that you
overhaul it. Because of the special tools
needed to do the job, it is best to let your
dealer service department overhaul it for you
(otherwise, fit a new unit). Removal and
refitting the steering box is outlined here.
1On 5-Series E28 (“old-shape”) models,
discharge the hydraulic system by depressing
the brake pedal about 20 times.
2Using a large syringe or hand pump, empty
the power steering fluid reservoir (see Chap-
ter 1).
3Raise the front of the vehicle and support it
securely on axle stands.
4Support the front of the engine with a trolley
jack. Place a block of wood between the jack
head and the sump to protect the sump from
damage.
5Remove the pivot bolts from the inner ends
of the front control arms (see Section 4).
6Remove the nuts from the left and right
engine mountings (see Chapter 2).
7Remove the mounting bolts (two on each
side on earlier models, three on each side on
later models) from the subframe crossmember
(see illustration)and remove the subframe.
8Remove the nuts and bolts that secure the
universal joint shaft to the steering box worm
shaft. Slide the universal joint shaft up and off
the worm shaft. Inspect the universal joint
shaft for wear. If it’s stiff or worn, renew it.
9Remove the banjo bolts, and disconnect
the hydraulic pressure line and the return line
from the box (see illustration). Plug the ends
of the lines to prevent fluid loss and
contamination. Discard the sealing washers -
new ones should be used when reassembling.
10Remove the steering box retaining bolts
(see illustrations)and remove the steering
box.
11If it’s necessary to detach the Pitman arm
from the box sector shaft (to have the box
serviced or to switch the arm to a new orrebuilt unit), make a match mark across the
two for correct reassembly. Remove the
Pitman arm retaining nut and washer. Use a
puller to withdraw the arm if necessary.
Refitting
12Refit the Pitman arm by aligning the
match marks made during removal, then
tighten the nut to the torque listed in this
Chapter’s Specifications.
13When fitted the Pitman arm must not have
any measurable endfloat within 100° from the
neutral position. If play exists, have the
following parts checked:
a) Sector shaft and bearings (for wear)
b) Thrust washer and adjuster bolt head (for
wear)
c) Ball nut and worm shaft (for wear)
14Refit the steering box. Align the mark on
the pinion gear shaft with the mark on the
universal joint shaft, and tighten the steering
box bolts to the torque listed in this Chapter’s
Specifications.
15The remainder of refitting is the reverse of
removal. Be sure to use new self-locking nuts
on the universal joint shaft, the centre track
rod, the steering box and the crossmember.
Also, use new sealing washers on the
hydraulic line fittings.
16Refer to Chapter 1 and fill the powersteering reservoir with the recommended
fluid, then bleed the system as described in
Section 23. Check for leakage from the lines
and connections.22 Power steering pump-
removal and refitting
1
Removal
1Raise the vehicle and support it securely on
axle stands. Remove the engine undertray.
2On 5-Series E28 (“old-shape”) models,
discharge the hydraulic system by depressing
the brake pedal about 20 times before
loosening the hydraulic line fittings.
3Disconnect the fluid return hose, and drain
the power steering fluid from the reservoir into
a clean container. Disconnect the pressure
line from the pump.
4If you need to remove the pulley from the
pump, push on the power steering pump
drivebelt by hand to increase the tension, and
unscrew the pulley nuts or bolts.
5Loosen the power steering pump drivebelt
tensioner bolt, and remove the drivebelt (see
Chapter 1).
6Remove the mounting bolts (see
illustrations)and detach the power steering
pump.
Suspension and steering systems 10•15
21.10a This bolt (arrowed) secures the
steering box to the subframe
crossmember. The nut, not visible in this
photo, is accessed through a hole in the
crossmember (engine removed for clarity,
left-hand-drive shown)21.9 Disconnect the power steering
pressure line fitting (right arrow) and the
return line fitting (left arrow). Note that the
return line fitting banjo bolt is larger than
the bolt for the pressure line fitting (left-
hand-drive shown)21.7 Subframe crossmember bolts
(arrowed)
22.6a Typical 3-Series power steering
pump adjusting bolt (arrowed) . . .
21.10b This bolt (arrowed) attaches the
steering box to the body (the nut, not
visible in this photo, is on the front side of
the steering box)
10
Refitting
7Refitting is the reverse of removal. Tighten
the nuts and bolts securely. Adjust the
drivebelt tension (see Chapter 1).
8Top-up the fluid level in the reservoir (see
Chapter 1) and bleed the system (see Sec-
tion 23).
23 Power steering system-
bleeding
1
1To bleed the power steering system, begin
by checking the power steering fluid level and
adding fluid if necessary (see Chapter 1).
2Raise and support the front of the vehicle
on axle stands.
3Turn the steering wheel from lock-to-lock
several times. Recheck the fluid level and top
up if necessary.
4Start the engine and run it at 1000 rpm or
less. Turn the steering wheel from lock-to-
lock again (three or four times) and recheck
the fluid level one more time. Note:On 5-Series E28 (“old-shape”) models, pump the
brake pedal five or six times before turning the
steering wheel. Once the fluid level remains
constant, continue turning the wheel back and
forth until no more bubbles appear in the fluid
in the reservoir.
5Lower the vehicle to the ground. Run the
engine and again turn the wheels from lock-
to-lock several more times. Recheck the fluid
level. Position the wheels straight-ahead.24 Steering wheel-
removal and refitting
1
Warning: If the vehicle is
equipped with an airbag, do not
attempt this procedure. Have it
performed by a dealer service
department or other qualified specialist, as
there is a risk of injury if the airbag is
accidentally triggered.
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.
2Using a small screwdriver, prise off the
BMW emblem in the centre of the steering
wheel.
3Remove the steering wheel nut, and mark
the relationship of the steering wheel hub to
the shaft (see illustration).
4On all 3-Series models, and on 1986 and
later 5-Series models, turn the ignition key to
the first position to unlock the ignition lock.
5Remove the steering wheel from thesteering shaft. If the wheel is difficult to
remove from the shaft, use a steering wheel
puller to remove it - don’t hammer on the
shaft.
Refitting
6Refitting is the reverse of removal. Be sure
to align the match marks you made on the
steering wheel and the shaft. Tighten the
steering wheel nut to the torque listed in this
Chapter’s Specifications.
25 Wheels and tyres-
general information
1
Note:For more information on care and
maintenance of tyres, refer to Chapter 1.
1All vehicles covered by this manual are
equipped with steel-belted radial tyres as
original equipment. Use of other types or
sizes of tyres may affect the ride and handling
of the vehicle. Don’t mix different types or
sizes of tyres, as the handling and braking
may be seriously affected. It’s recommended
that tyres be renewed in pairs on the same
axle; if only one new tyre is being fitted, be
sure it’s the same size, structure and tread
design as the other.
2Because tyre pressure has a substantial
effect on handling and wear, the pressure on
all tyres should be checked at least once a
month or before any extended trips (see
Chapter 1).
3Wheels must be renewed if they are bent,
heavily dented, leak air, or are otherwise
damaged.
4Tyre and wheel balance is important in the
overall handling, braking and performance of
the vehicle. Unbalanced wheels can adversely
affect handling and ride characteristics, as
well as tyre life. Whenever a new tyre is fitted,
the tyre and wheel should be balanced.
10•16 Suspension and steering systems
24.3 After removing the steering wheel
nut, mark the relationship of the steering
wheel to the steering shaft (arrowed) to
ensure proper alignment during
reassembly
22.6c Typical 5-Series power steering pump mounting bolts
(arrowed)22.6b . . . and mounting nut and bolt (arrowed)
REF•8General Repair Procedures
Whenever servicing, repair or overhaul work
is carried out on the car or its components,
observe the following procedures and
instructions. This will assist in carrying out the
operation efficiently and to a professional
standard of workmanship.
Joint mating faces and gaskets
When separating components at their
mating faces, never insert screwdrivers or
similar implements into the joint between the
faces in order to prise them apart. This can
cause severe damage which results in oil
leaks, coolant leaks, etc upon reassembly.
Separation is usually achieved by tapping
along the joint with a soft-faced hammer in
order to break the seal. However, note that
this method may not be suitable where
dowels are used for component location.
Where a gasket is used between the mating
faces of two components, a new one must be
fitted on reassembly; fit it dry unless otherwise
stated in the repair procedure. Make sure that
the mating faces are clean and dry, with all
traces of old gasket removed. When cleaning a
joint face, use a tool which is unlikely to score
or damage the face, and remove any burrs or
nicks with an oilstone or fine file.
Make sure that tapped holes are cleaned
with a pipe cleaner, and keep them free of
jointing compound, if this is being used,
unless specifically instructed otherwise.
Ensure that all orifices, channels or pipes
are clear, and blow through them, preferably
using compressed air.
Oil seals
Oil seals can be removed by levering them
out with a wide flat-bladed screwdriver or
similar implement. Alternatively, a number of
self-tapping screws may be screwed into the
seal, and these used as a purchase for pliers or
some similar device in order to pull the seal free.
Whenever an oil seal is removed from its
working location, either individually or as part
of an assembly, it should be renewed.
The very fine sealing lip of the seal is easily
damaged, and will not seal if the surface it
contacts is not completely clean and free from
scratches, nicks or grooves. If the original
sealing surface of the component cannot be
restored, and the manufacturer has not made
provision for slight relocation of the seal
relative to the sealing surface, the component
should be renewed.
Protect the lips of the seal from any surface
which may damage them in the course of
fitting. Use tape or a conical sleeve where
possible. Lubricate the seal lips with oil before
fitting and, on dual-lipped seals, fill the space
between the lips with grease.
Unless otherwise stated, oil seals must be
fitted with their sealing lips toward the
lubricant to be sealed.
Use a tubular drift or block of wood of the
appropriate size to install the seal and, if the
seal housing is shouldered, drive the seal
down to the shoulder. If the seal housing isunshouldered, the seal should be fitted with
its face flush with the housing top face (unless
otherwise instructed).
Screw threads and fastenings
Seized nuts, bolts and screws are quite a
common occurrence where corrosion has set
in, and the use of penetrating oil or releasing
fluid will often overcome this problem if the
offending item is soaked for a while before
attempting to release it. The use of an impact
driver may also provide a means of releasing
such stubborn fastening devices, when used
in conjunction with the appropriate
screwdriver bit or socket. If none of these
methods works, it may be necessary to resort
to the careful application of heat, or the use of
a hacksaw or nut splitter device.
Studs are usually removed by locking two
nuts together on the threaded part, and then
using a spanner on the lower nut to unscrew
the stud. Studs or bolts which have broken off
below the surface of the component in which
they are mounted can sometimes be removed
using a stud extractor. Always ensure that a
blind tapped hole is completely free from oil,
grease, water or other fluid before installing
the bolt or stud. Failure to do this could cause
the housing to crack due to the hydraulic
action of the bolt or stud as it is screwed in.
When tightening a castellated nut to accept
a split pin, tighten the nut to the specified
torque, where applicable, and then tighten
further to the next split pin hole. Never slacken
the nut to align the split pin hole, unless stated
in the repair procedure.
When checking or retightening a nut or bolt
to a specified torque setting, slacken the nut
or bolt by a quarter of a turn, and then
retighten to the specified setting. However,
this should not be attempted where angular
tightening has been used.
For some screw fastenings, notably
cylinder head bolts or nuts, torque wrench
settings are no longer specified for the latter
stages of tightening, “angle-tightening” being
called up instead. Typically, a fairly low torque
wrench setting will be applied to the
bolts/nuts in the correct sequence, followed
by one or more stages of tightening through
specified angles.
Locknuts, locktabs and washers
Any fastening which will rotate against a
component or housing during tightening
should always have a washer between it and
the relevant component or housing.
Spring or split washers should always be
renewed when they are used to lock a critical
component such as a big-end bearing
retaining bolt or nut. Locktabs which are
folded over to retain a nut or bolt should
always be renewed.
Self-locking nuts can be re-used in non-
critical areas, providing resistance can be felt
when the locking portion passes over the bolt
or stud thread. However, it should be noted
that self-locking stiffnuts tend to lose theireffectiveness after long periods of use, and
should then be renewed as a matter of course.
Split pins must always be replaced with
new ones of the correct size for the hole.
When thread-locking compound is found
on the threads of a fastener which is to be re-
used, it should be cleaned off with a wire
brush and solvent, and fresh compound
applied on reassembly.
Special tools
Some repair procedures in this manual
entail the use of special tools such as a press,
two or three-legged pullers, spring com-
pressors, etc. Wherever possible, suitable
readily-available alternatives to the manu-
facturer’s special tools are described, and are
shown in use. In some instances, where no
alternative is possible, it has been necessary
to resort to the use of a manufacturer’s tool,
and this has been done for reasons of safety
as well as the efficient completion of the repair
operation. Unless you are highly-skilled and
have a thorough understanding of the
procedures described, never attempt to
bypass the use of any special tool when the
procedure described specifies its use. Not
only is there a very great risk of personal
injury, but expensive damage could be
caused to the components involved.
Environmental considerations
When disposing of used engine oil, brake
fluid, antifreeze, etc, give due consideration to
any detrimental environmental effects. Do not,
for instance, pour any of the above liquids
down drains into the general sewage system,
or onto the ground to soak away. Many local
council refuse tips provide a facility for waste
oil disposal, as do some garages. If none of
these facilities are available, consult your local
Environmental Health Department, or the
National Rivers Authority, for further advice.
With the universal tightening-up of legis-
lation regarding the emission of environmen-
tally-harmful substances from motor vehicles,
most vehicles have tamperproof devices fitted
to the main adjustment points of the fuel
system. These devices are primarily designed
to prevent unqualified persons from adjusting
the fuel/air mixture, with the chance of a
consequent increase in toxic emissions. If
such devices are found during servicing or
overhaul, they should, wherever possible, be
renewed or refitted in accordance with the
manufacturer’s requirements or current
legislation.
Note: It is
antisocial and
illegal to dump
oil down the
drain. To find
the location of
your local oil
recycling
bank, call this
number free.