BMW 01 41 0 155 307 - Manual (Page 142)

142 n Caring for your vehicle
Exterior finish
To provide effective corrosion protec-
tion, multilayer paintwork is applied at
the factory. Cataphoretic immersion
priming techniques are supplemented
with special body-cavity protectants,
by applying specially-developed and
extensively tested materials.
A layer of flexible PVC is first applied
to the undercarriage. Following this,
a comprehensive undercoating treat-
ment with a wax-based protectant is
applied. Regular maintenance makes
an important contribution to maintaining
the safety and value of your vehicle.
Increasing awareness of the effects of
harmful environmental factors on vehi-
cle finishes have led paint and vehicle
manufacturers to initiate programs
designed to further improve the durabil-
ity of their finishes. Despite this, envi-
ronmental factors that occur locally or
regionally can have negative effects on
the finish of your vehicle. Use the
factors to determine the frequency and
extent of your efforts to maintain the
vehicle finish.
Depending upon material and type of
impact (perforation of paint layer),
physical stresses from sand, road salt,
gravel, etc., can cause corrosion to start
extending beneath the finish, starting at
the point of impact.
Road dirt, tar spots, dead insects,
animal droppings (strong alkali effect)
and tree excretions (resins and pollen)
all contain substances capable of
causing damage when allowed to
remain on the finish of your vehicle for
any extended period of time (spots,
etching, flaking, separation in the top
coat).
In industrial areas, flue dust deposits,
lime, oily soot, precipitation containing
sulfur-dioxide (acid rain) and other envi-
ronmental pollutants will damage the
vehicle's finish unless adequate care is
provided – even though this is generally
limited to the outside horizontal sur-
faces.
In coastal regions, high levels of
atmospheric salt and humidity promote
corrosion.
In tropical zones, temperatures of over
+105 7 (+40 6) in the shade prevail,
in addition to heavy ultraviolet radiation
and high humidity. Under those condi-
tions, light paints can reach tempera-
tures up to +175 7 (+80 6) and dark
paints up to +250 7 (+120 6).
Online Edition for Part No. 01 41 0 155 307 - © 09/00 BMW AG