Test Five - Governor Pressure
NOTE: This test checks governor operation by measuring governor pressure response to changes in vehicle speed. It is usually not necessary to check governor operation unless shift speeds are incorrect or if the transmission will not downshift. The test should be performed on the road or on a hoist that will allow the rear wheels to rotate freely.1. Move 100 psi Test Gauge C-3292, or equivalent to governor pressure port.
2. Move transmission shift lever two detents rearward from full forward position. This is D range.
3. Have helper start and run engine at curb idle speed. Then firmly apply service brakes so wheels will not rotate.
4. Note governor pressure:
- Governor pressure should be no more than 20.6 kPa (3 psi) at curb idle speed and wheels not rotating.
- If pressure exceeds 20.6 kPa (3 psi), a fault exists in governor pressure control system.
5. Release brakes, slowly increase engine speed, and observe speedometer and pressure test gauge (do not exceed 30 mph on speedometer). Governor pressure should increase in proportion to vehicle speed. Or approximately 6.89 kPa (1 psi) for every 1 mph.
6. Governor pressure rise should be smooth and drop back to no more than 20.6 kPa (3 psi), after engine returns to curb idle and brakes are applied to prevent wheels from rotating.
7. Compare results of pressure test with analysis chart.