BCDD Operating Vacuum
- Warm engine to normal operating temperature. Ensure idle speed is set to specifications and place transmission in Neutral. Disconnect solenoid harness (if equipped). Connect a vacuum gauge to intake manifold.
- Run engine under no load conditions and note vacuum reading. Increase engine speed to 3000-3500 RPM, then quickly close throttle. Manifold vacuum should increase to 24 in. Hg or more and then gradually decrease to level noted at idle.
- If BCDD operating vacuum at idle is not as specified in BCDD OPERATING VACUUM table, turn adjusting screw/nut as necessary until specified operating vacuum is obtained. See Fig 1 and Fig 3.
- Turning adjusting SCREW counterclockwise increases operating vacuum. Turning adjusting NUT clockwise increases operating vacuum. Turn adjusting nut in or out with lock spring in place. Always set lock spring properly to prevent changes in operating pressure.
BCDD OPERATING VACUUM
| Application | In. Hg | |
|---|---|---|
| B210 & F10 | 20-21 | |
| 200SX, 510 & Pickup | ||
| Federal | 21-22 | |
| Calif. | 22-23 | |
| 280Z & 280ZX | 17-19 | |
| 810 | 19-20 | |