Vacuum Regulator Valve
The vacuum regulator valve provides vacuum signals to control automatic transmission shift points. Vacuum setting of valve should be checked periodically, using the following procedure. Engine MUST NOT be running during this procedure.
- Disconnect 2-port vacuum connector from vacuum regulator valve, located on left side of injection pump. See Fig 2 . Remove throttle cable from pump throttle lever, located on right side of pump.
- Remove throttle return spring and reposition. Place end of spring over throttle lever ball stud and other end over throttle cable support bracket. Attach a hand-held vacuum pump to upper port of vacuum regulator valve.
- Attach vacuum gauge to lower port (labeled "TRANS") of regulator valve. See Fig 1 . Apply and maintain 20 in. Hg to vacuum regulator valve. It will be necessary to increase vacuum as regulator valve bleeds off.
- Cycle throttle lever 5 times from idle to wide open throttle with vacuum applied. Insert Gauging Block (T83T-7B200-AH) between pump boss and wide open throttle stop. See Fig 2 .
- Repositioned spring should hold throttle lever stop against block. Vacuum gauge attached to regulator valve should indicate 6-8 in. Hg. If not, adjust regulator valve.
- To adjust valve, loosen vacuum regulator valve screws and rotate valve until vacuum gauge reads 7 in. Hg. Tighten screws. If valve cannot be adjusted to specification, replace regulator valve and repeat adjustment procedure.
- Remove gauging block. Reconnect throttle return spring in original position and connect throttle cable. Apply 20 in. Hg to vacuum regulator valve. While maintaining vacuum, cycle throttle lever 5 times from idle to wide open throttle.
- Vacuum gauge must indicate at least 13 in. Hg with throttle at idle. If reading is less than 13 in. Hg, replace vacuum regulator valve and repeat adjustment procedure. If reading is correct, remove vacuum pump and gauging block. Attach vacuum connector.