Toyota 4-Runner 1985 Repair Manual page 250

FUEL SYSTEM - Carburetor FU-7
FU0265
FU0266
5. REMOVE POWER PISTON
(a) Loosen the retainer screw.
(b) While holding the piston, rotate the retainer.
(c) Remove the power piston and spring.
6. REMOVE OUTER VENT CONTROL VALVE
Loosen the three screws and remove the outer vent con-
trol valve.