BMW M COUPE Manual page 135

Caring for your car
Rear window cleaning
While the roadster's rear window has
the advantage of being extremely flexi-
ble, there is the disadvantage that it has
a relatively-soft surface. For this rea-
son, clean the rear window only with a
soft, antistatic cloth or with BMW Con-
vertible Rear Window Cleaner.
If you wash the vehicle frequently in
brush car washes, and in particular in
those with hard brushes, faint scratches
in the rear window may result. With the
window replacement system you can
replace a heavily scratched window at a
relatively low price. Please contact your
BMW center for additional information.
Do not use spot removers, paint
thinners, solvents, gasoline or
similar substances for removing spots
from the convertible top or from the
rear window. These materials destroy
the rubber seals, which will lead to
leaks. Use only BMW-approved clean-
ers.<
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 impor-
tant 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 de-
signed to further improve the durability
of their finishes. Despite this, environ-
mental factors which 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, start-
ing at the point of impact.
Road dirt, tar spots, dead insects, ani-
mal droppings (strong alkali concentra-
tion) and tree excretions (resins and
pollen) all contain substances capable
of causing damage when allowed to
remain on the finish of your car for any
period of time (spots, etching, flaking,
separation in the top coat).
In industrial areas, deposits of flue dust,
lime, oily soot, precipitation containing
sulfur-dioxide (acid rain) and other envi-
ronmental pollutants will damage the
car's finish unless adequate care is pro-
vided – even though this is generally
limited to the outside horizontal sur-
faces.
In coastal regions, high levels of atmo-
spheric salt and humidity promote cor-
rosion.
In the tropics, in addition to ultra-violet
radiation and high humidity, tempera-
tures over 105 7 (40 6) in the shade
are common. Under those conditions,
light paints can reach temperatures up
to 175 7 (80 6) and dark paints up to
250 7 (120 6).
Online Edition for Part-No. 01 41 0 155 149 - © 08/99 BMW AG
135n