Using Engine Vacuum
- If vacuum diaphragm unit is working properly and linkage is adjusted correctly, all shifts should occur within specified road speed limits. See appropriate SHIFT SPEEDS table. If not within specifications or slipping occurs, check engine vacuum supply and vacuum operated units for possible defect.
- Connect tachometer to engine. Connect vacuum gauge to manifold vacuum line, using "T" fitting at diaphragm unit. Attach pressure gauge to control pressure take-off located on left side of transmission case. See Fig 1.
- Apply parking brake firmly. Start engine and ensure idle RPM is correct. If engine idle cannot be brought within limits, check throttle and downshift linkages for binding. Check for vacuum leaks in hoses, tubes and all vacuum components such as power brake booster.
- With engine at idle, read and record control pressures in all selector positions. Read and record control pressures with vacuum gauge reading at 10 in. Hg and at one in. Hg (wide open throttle). See appropriate CONTROL PRESSURE SPECIFICATIONS and CONTROL PRESSURE TEST RESULTS .
NOTE:
Governor can be checked at same time and in the same manner as control pressure test.