Porsche 911 TURBO - 1989 Workshop Manual page 138

Exhaust System
REMOVING AND INSTALLING AIR PUMP
Removing
1. Loosen bolts and hoses on diverter valve and
remove valve.
3. Loosen nut on bracket and bolts on air pump
mount.
4. Peel off toothed belt and remove air pump
with mount.
2. Loosen clamps and remove hose between
mixture control unit and valve housing.
Installing
1. Install air pump with air pump mount and
install toothed belt.
2. Press air pump to the left slightly and tighten
the bolt on air pump bracket. Under thumb
pressure, the toothed belt should deflect (at
midpoint) by 6 -8 mm (1/4 to 5/16 in.).
Printed in Germany
26 -22
Removing and Installing Air Pump