Porsche 928 1982 Owner's Manual page 71

The collapsible spare tire cannot be re-
paired or mounted with standard work-
shop equipment. Repair and remounting
must only be done by the manufacturer.
Tire tread depth
As required by law, the tread depth of the
collapsible tire is the same as that of the
original equipment tire. Replace a worn col-
lapsible spare tire in time.
If air compressor does not work
...Check if tobacco or any other foreign
matter is lodged in the cigarette lighter
socket. Remove carefully with a wooden
pick. Do not use metal object to prevent
short circuit.
... Check if fuse is blown. Replace with new
equivalent fuse.
Maintenance of air compressor
The air compressor is maintenance-free. Do
not apply oil or any other lubricant.
The air filter should be cleaned periodically
to assure maximum efficiency of the unit.
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