Brake Pedal - Porsche 928 1982 Owner's Manual

Brake pedal

Your Porsche is equipped with a hydraulic
dual circuit brake system with self adjusting
disc brakes at the front and rear. Make it a
habit to check the operation of your brakes
before driving off. The movement of the brake
pedal should not be obstructed by a floor mat
or other objects.
Do not "ride the brakes" by resting your foot
on the pedal when not intending to brake.
Overheating and wear of the brakes is the re-
sult.
With correctly adjusted brakes, and a correct-
ly working brake system, the pedal travel to
the point of brake actuation should be 1-3/16"
to 1 -9/16" or 30 to 40 mm. Whenever the brake
pedal travel exceeds this distance, have the
brake system checked.
Keep in mind that the braking distance in-
creases very rapidly as the speed increases.
At 60 mph or 96 km/h, for example, it is not
twice but four times longer than at 30 mph
or 48 km/h. Tire traction is also less effective
when the roads are wet or slippery. Therefor,
always maintain a safe distance.
Moisture or road salt on brakes
affects braking
Driving through water may reduce tire trac-
tion. Moisture on brakes from road water
or car wash or coating of road salt may af-
fect braking efficiency. Cautiously apply
brakes for a test. Brakes will dry and salt
coating will be cleaned off after a few cau-
tious brake applications.
Brake booster
The brake booster assists braking only when
the engine is running. When the car is moving
while the engine is not running, or if the brake
booster is defective, more pressure on the
brake pedal is required to bring the car to a
halt.
Brake warning lights
The central warning light and the brake fluid
warning light in the combination instrument
will flash when the level in the brake fluid re-
servoir is too low. To report a brake circuit
failure, the central warning light and the brake
pressure warning light will flash (see "Central
warning light system").
Clutch
Due to the hydraulic operation of the clutch,
a free travel of the clutch pedal of 0 , 1 " or
2.5 mm is necessary.
Should this free travel suddenly become
bigger, it could mean a malfunction of the
clutch. See your Porsche dealer for recti-
fication.
The specified maximum rpm figures should
not be exceeded when shifting down, as
otherwise the engine speed would be too
high. This applies to standard gear ratios
only.
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