Porsche 928 ST1991 Owner's Manual page 80

Door, roof and window seals
Rubber seals tend to age and become brittle
or crack if they are not treated occasionally
with glycerine or talcum powder.
Light alloy wheels
Pitting may occur if metallic particles which
cause contact corrosion (e.g. brass or cop-
per in brake dust) are allowed to remain on
the aluminium for too long.
Regular care is necessary in order to retain
the attractive surface finish. The wheels
should be washed down with a sponge or
wash brush about every two weeks. In areas
where salt is spread on winter roads or there
is a lot of airborne industrial dust, it is best
to clean the wheels weekly.
The Porsche Light Alloy Wheel Cleaner (pH-
value 9.5) can be used for this purpose.
If the pH-value of the detergent is incor-
rect, the protective coating on the wheels
will be destroyed.
Every three months you should coat the
wheels with a non-corrosive grease (vas-
eline) after cleaning. Using a clean cloth
thoroughly rub the grease into the surface.
Polishes which dissolve oxides, as fre-
quently used for other metals, or abrasive
tools or agents are unsuitable because
they break down the oxide film of the pro-
tective coating and will cause discolora-
tion of the wheel.
Leather care
Leather is a natural material. The tanned hide
is a product of nature. The natural surface
markings of leather skins, such as creases,
healed scratches, insect bites, structural dif-
ferences and slight variations in shade and
grain add to the attractiveness of the real
leather product.
We recommend that the leather be treated
or cleaned initially after the first few weeks
or after the car has covered a few thousand
miles. Only by doing so can the leather
patina, which emphasizes the inherent qual-
ities of the leather upholstery, begin to form.
Cleaning is best performed with a white, soft
woolen cloth and a cleaning agent with a
neutral soap basis (mild soap and water sol-
ution). If the leather is heavily soiled the
Porsche Cockpit Cleaner can also be used.
Please follow the instructions on the contain-
ers carefully.
Do not use aggressive cleaners or hard ob-
jects.
Take special care not to dampen the other
side of the perforated leather trims.
Once you have cleaned the leather (espe-
cially the heavily used leather seats) treat it
with the Porsche Leather Care Agent.
Leather should be cleaned and treated sev-
eral times a year, depending on how quickly
it becomes dirty.
Should the leather become damaged during
use (e. g. when transporting sharp objects or
if tools etc. should slip) the damage can be
made less conspicuous using the Porsche
Leather Color Coating.
Fabric, upholstery and carpets
Use only a vacuum cleaner or a medium stiff
brush. Remove stains and spots with
Porsche stain remover.
The Porsche range of accessories includes
floormats to protect the carpets in Summer
and Winter.
79