BMW 5251 Service Manual page 47

Maintenance
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Release mass air flow sensor clips (A).
Release upper air filter housing clips (B).
4
Lift air filter upper housing, and remove filter element.
NOTE-
V-8 engine air filter assembly shown
in
illustration. 6-cylinder
air filter assembly is similar but located at the left front of the
engine compartment.
-
On installation, install O-ring for mass air flow sensor into
retaining clips in air filter upper housing.
-
Replace air filter and upper air filter housing, and attach
upper air filter housing clips.
Cooling system, checking
Antifreeze raises the boiling point and lowers the freezing
~ o i n t of the coolant. BMW recommends enaine coolantthat is
a
50
150 mixture of distilled water and ethGene glycol-based
antifreeze.
Routine cooling system maintenance consists of maintaining
the coolant level and inspecting hoses. Because the coolant's
anticorrosion and antifreeze additives gradually lose their ef-
fectiveness, replacement of the coolant every three years is
recommended.
CAUJION-
Use only BMWapprovedphosphate-free antifreeze when
filing
the cooling system. Use of antifreeze containing
phosphates is harmful to the cooling system.
4
Float in radiator tank indicates coolant level. Inspect while
coolant is cold.
When upper mark on float is level with top of filler neck,
coolant is at minimum allowable level.
When lower mark on float is level with top of filler neck,
coolant is at maximum level.
Hose connections should be tight and dry. Coolant seepage
nnection indicates either that hose clamp is