Caring for your vehicle – BMW 2006 bmw 325i User Manual

Page 147

147

Index

Data

Technology

Repairs

Car care

Controls

Overview

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
using special body-cavity protectants,
with the application of specially-devel-
oped 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
vehicle finishes have urged paint and
vehicle manufacturers to initiate
ongoing programs designed to further
improve the durability of their finishes.
Despite this, environmental factors that
occur locally or regionally can have
negative effects on the finish of your
vehicle. These should guide you in
determining 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 caus-
ing damage when allowed to remain on
the finish of your vehicle for any period
of time. This includes spots, etching,
flaking, and separations in the top coat.

In industrial areas, deposits of flue dust,
lime, oily soot, precipitation containing
sulfur-dioxide (acid rain) and other
environmental pollutants will damage
the vehicle's finish unless adequate
care is provided – even though this is
generally limited to the outside
horizontal surfaces.

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).