1999 BMW 528i Air hose

Downloaded from www.Manualslib.com manuals search engine
170-8
I Radiator and Cooling System
Common cooling system faults can be grouped into one of 4
categories:
Cooling system
lealts
Poor coolant circulation
Radiator cooling fan faults
Electrical/electronic faults
Cooling system inspection
- Check that coolant pump drive belt tensioner is functioning
properly and that belt tension is correct. Belt tensioner sys-
tems for the different models are shown in
020 Maintenance.
- Check condition of coolant pump drive belt.
- Checlc coolant hoses for cracks or softness. Checlc clamps
for looseness. Check coolant level and check for evidence of
coolant
lealts from engine.
- Check that radiator fins are not blocked with dirt or debris.
Clean radiator using low-pressure water or compressed air.
Blow outward, from engine side out.
- To check coolant pump:
Remove mechanical cooling fan. See Mechanical
(vis.
cous clutch) cooling fan, removing and installing.
Remove drive belt from coolant pump pulley. See
020
Maintenance.
Firmly grasp opposite sides of pulley and check for play in
all directions.
Spin pulley and check that shaft runs smoothly without
play.
NOTE-
The coolant provides lubrication for the pump shaft, so an oc-
casional drop of coolant
lealing from the pump is acceptable.
If coolant drips steadily from the vent hole, replace the pump.
- At normal engine operating temperature, cooling system is
pressurized. This raises boiling point of coolant.
Leaks may
prevent system from becoming pressurized. If visual evi-
dence is inconclusive, pressure test cooling system as de-
scribed later to help pinpoint hard-to-find leaks.
- If cooling system is full of coolant and holds pressure:
- Use an appropriate scan tool to interrogate engine control
module (ECM) for radiator fan or DME control circuit faults.
Checlc for loose or worn drive belt.
0 Test for failed thermostat or coolant pump impeller. Some
pumps may be fitted with plastic impellers.

Downloaded from www.Manualslib.com manuals search engine
Radiator and Cooling System
Cooling system, bleeding
Trapped air in the cooling system can prevent proper coolant
circulation and overheating. Wheneverthe coolant is drained
and filled, bleed the cooling system to remove trapped air.
4 Loosen bleed screw (arrow) on radiator expansion tank.
- Set temperature controls in passenger compartment to full
warm, set blower to low setting and turn ignition to
ON posi-
tion (do not start engine).
CAUTIOIG
On late model cars with latent heat pump, do not turn ignition
to ON position.
- Slowly add coolanUdistilled water mixture to expansion tank
until it spills from bleed screw. When coolant spilling from
bleed screws is free of air bubbles, tighten screw and replace
cap on expansion tank.
Run engine until it reaches operating temperature,
- After engine has cooled, recheck coolant level.
Top up so that coolant level indicator is at MAX.
- If trapped air cannot be bled manually, pressure-bleed sys-
tem using cooling system pressure tester.
CA UTlON--
Always use genuine BMW coolant or its equivalent to avoid
the formation of harmful, clogging deposits
in the cooling sys-
tem.
Tightening torque
Radiator bleed screw to radiator 2.5 Nm (22 in-lb)
Mechanical (viscous clutch) cooling fan,
removing and installing
The procedure given here describes the removal of the me-
chanical fan and fan shroud. It is possible to remove the fan
without the shroud.
< Working at top of fan shroud:
Remove expansion tank bleed screw (arrow) and expan-
sion tank locking tabs.
Push top of expansion
tank toward engine and lift to free
from lower mounts.
- Remove two expansion rivets in upper corners of fan shroud.
Unclip expansion tank bleed hose located under shroud.

Downloaded from www.Manualslib.com manuals search engine
Tightening torques Block drain plug to block
25 Nm (18 ft-lb)
Radiator drain plug to radiator 2 - 3 Nm (18 - 27 in-lb)
Thermostat housing to
cylinder head 10 Nm (89 in-lb)
Thermostat, removing and installing
(V-8 models)
The electrically-heated thermostat is an integral parl of the
thermostat housing. The operation of the thermostat is moni-
tored by the engine control module (ECM).
- If a faulty thermostat is suspected, use appropriate scan tool
to interrogate ECM for stored fault codes.
- Drain radiator and engine block. See Coolant, draining and
filling
(V-8 models).
WARNING -
Allow cooling system to cool before opening or draining the
system.
- Disconnect mass air flow (MAF) sensor electrical harness
connector. Remove air intake duct together with MAF sensor.
- Remove mechanical cooltng fan and fan shroud. See Me-
chanical (viscous clutch) cooling fan, removing and
in-
stalling.
Disconnect electrical harness connector (arrow) from ther-
mostat housing.
Remove coolant hose from thermostat housing.
NOTE-
M62 engine: Hose is clamped on.
M62 TU engine: Hose is attached with quick-disconnect fit.
ting. Remove clip to disconnect hose.

Downloaded from www.Manualslib.com manuals search engine
.," --
Radiator and Cooling System --- 1
insert two M6 screws (arrows) in tapped bores and tighten
uniformly until pump is free from timing chain cover (thermo-
stat and hoses have been removed for purposes of visual
clarity).
Installation is reverse of removal, noting the following:
Be sure to replace sealing O-ring and gaskets.
Coat O-ring with water-based lubricant during installation.
Refill with coolant. See Coolant, draining and filling
(6-
cylinder models).
Tightening torques
-
Coolant pump to timing chain 10 Nm (89 in-lb)
cover
Coolant pump pulley to coolant
10 Nm (89 in-lb
pump
Engine block drain plug to block 25 Nm (1 8 It-lb)
Radiator drain plug to radiator 2 - 3 Nm (I8 - 27 in-lb)
Coolant pump, replacing (V-8 models)
I 1 < The engine coolant pump is mounted in the front of the en-
gine in ;he timing chain cover.
1. Thermostat housing
2. Thermostat
3. Thermostat sealing O-ring
4. Water pump
5. Water pump gasket
- Drain cooling system. See Coolant, draining and filling (V-
8 models).
- Remove cooling fan and fan shroud. See Mechanical (vis-
cous clutch) cooling fan, removing and installing.
- Remove engine drive belts: See 020 Maintenance.
NOTE-
Mark direction of drive belt rotation if reusing belt,
- Remove vibration dampener. See 117 Camshaft and Tim-
ing Chain.
- Disconnect mass air flow (MAF) sensor electrical harness
connector. Remove air intake duct together with
MAF sensor.
- Disconnect coolant hoses from thermostat housing and cool-
ant pump housing.

Downloaded from www.Manualslib.com manuals search engine
. --
Radiator and Cooling system/
4 Pry out expansion rivets (A) on left and right side of fan
shroud. Loosen hose clamp
(6) and remove hose from ex-
pansion tank.
Remove expansion tank: Remove expansion tanlc cap, vent plug
(A) and tank retain-
ing clips (arrows).
Lift expansion
tanlc upward and off lower retaining lugs.
Push shroud back to expose expansion tank vent line. Re-
move line.
Using 32 mm wrench
(BMW special tool 11 5 040) on fan
clutch nut (arrow), turn wrench in a clockwise direction
(working from front of car) while counterholding pulley with
BMW special tool 11 5 030. Spin fan off coolant pump.
NOTE-
The radiator cooling fan nut (32 mrn wrench) has left-hand
threads.
Disconnect electrical harnesses from
AUC (air quality) sen-
sor and coolant level sensor.

Downloaded from www.Manualslib.com manuals search engine
Anach pressure brake bleeder to fluid reservoir and pump
bleeder a few times to pressurize hydraulic fluid system.
CAUTION-
* Do not exceed 2 bar (29 psi) pressure at the fluid resenfoil
when bleeding or flushing the hydraulic system.
Brake fluid is poisonous, highly corrosive and danger-
ous to the environment. Wear safety glasses and
rub-
bergloves when working with brake fluid. Do not siphon
brale fluid with your mouth. Immediately clean away
any fluid spilled on painted surfaces and wash with wa-
ter, as brale fluid will remove paint.
Always use new brake fluid from a fresh, unopened
container.
Brake fluid will absorb moisture from the air.
This can lead to corrosion problems in the clutch and
brake hydraulic systems, ;nd will also lower the brake
fluid boiling point. Dispose of brale fluid properly.
- Raise and safely support vehicle.
WARNING-
Make sure the car is stable and well supported at all times.
Use a professional automotive lift orjackstands designed for
the purpose. A floor
iack is not adequate support.
- If necessary, remove transmission splash shield.
Hydraulic system, bleeding
Worlting underneath transmission, connect a hose from
clutch slave cylinder bleeder valve
(arrow) to a container.
Open bleeder valve and allow bralte fluid to expel until
clean fluid comes out, free of air bubbles.
Close bleeder valve and disconnect pressure bleeding
equipment from fluid reservoir.
Slowly operate clutch pedal about
10 times. Fill reservoir
with clean fluid as necessary.
CR* .,,, .rP,ll,h.:I,,~,~mn.lI","i,,i"

Downloaded from www.Manualslib.com manuals search engine
230-1 8
Manual Transmission
- Unbolt clutch slave cylinder from side of transmission. Do not
disconnect fluid hose. Suspend slave cylinder from chassis
using stiff wire.
CA UTIOG
Unbolt clutch slave cylinder slowly to prevent air being
drawn into hydraulic system.
. Do not operate clutch pedal with slave cylinder re-
moved from transmission.
4 Put BMW special tool 11 7 370 or appropriate sized spacer
between engine oil sump and front axle support. Lower trans-
mission until engine is supported on spacer.
0 V-8 vehicle: Turn front wheels to prevent strain from being
placed on center tie rod.
All vehicles: Tilting the engine to lower the transmission
can lead to damage to various components due to lack
of clearance at rear of engine. Lower transmission
slowly
- Support front of engine with floor jack.
4 Disconnect shift rod from selector shaft coupling
- Disconnect shift console from top of transmission. See 250
Gearshift Linkage.
6-cylinder: Remove transrnisslon mounting Torx-head bolts
(arrows). Note length and locatlon of bolts.
Remove
transrnlssion by pulling backward untll transmls-
sion Input shaft clears clutch d~sc spl~nes, then pull down-
wards. Lower
transmlsslon jack to remove transrnlsslon. -
- - -
-

Downloaded from www.Manualslib.com manuals search engine
I Steerina and Wheel Alianment
Steering
system
Two types of steering gear are used in the E39 series models.
6-cylinder
(5251, 528i and 530i) models are equipped with
rack and pinion steering. The steering rack is mounted to
an aluminum subframe.
V-8
(540i) models are equipped with a recirculating ball
and nut steering gearbox mounted to a steel subframe.
At low speeds, maximum power assist is provided to ease
parking and city driving. At high speeds, assist is reduced to
ensure stability. The power steering system varies assist
based on engine speed.
Power boost for the steering is provided by an engine-driven
hydraulic pump. A hydraulic control valve is used to control
boost pressure.
The steering wheel connects to the steering gear via an ad-
justable steering column which incorporates a rubber cou-
pling ("guibo") to dampen vibration and noise.
Power steering fluid is supplied from the fluid
reservoir to the
pump and to the steering gear via rubberlmetal hoses.
The return line from the steering gear to the
reservoir loops
into the airstream in front of the radiator and connects to the
steering fluid cooler. The fluid cooler is attached to a cassette
which also includes cooling coils for engine oil, transmission
fluid and AIC condenser.
The steering gear requires no maintenance other than align-
ment and periodic inspection for worn components. Inspect
rubber rack boots
(rack and pinion system) and tie-rod end
boots periodically for tears or damage. Replace
if necessary.
-
NOTE-
The airbag system is traditionally referred to as Supplemen-
tal Restraint System (SRS). The
BMW versfon of SRS used
m the E39 models is known as the Multiple Restraint System - (MRS). - -