The following test procedure will check the pressure of the charge oil that is being delivered from a modulating valve (transmission) to a transmission clutch. There are nine individual modulating valves that control the nine transmission clutches. The modulating valves (transmission) are modulated. The modulation of these valves can be adjusted.
| |
| Illustration 1 | g00800009 |
|
Tooling (K) | |
Use the tools in Table 1 to complete the following test procedure.
| Required Tools (Pressure Gauges) | ||||
|---|---|---|---|---|
| Tool | Item | Part Number | Description | Qty |
| K | K1 | 6V-3989 | Fitting (Test) | 2 |
| K2 | 8T-0855 | Pressure Gauge | 2 | |
| K3 | 177-7861 | Hose As | 2 | |
| K4 | 6V-4143 | Coupler | 4 | |
| 143-4065 | Pressure Sensor
|
1 | ||
 |
|
Sudden movement of the machine or release of oil under pressure can cause serious injury to persons on or near the machine. To prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic system. |
| NOTICE |
|---|
|
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Dispose of all fluids according to local regulations and mandates. |
Pressure gauges are used in the following test procedure.
| |
| Illustration 2 | g01325496 |
|
Transmission Clutches | |
The designated letters are used to correlate a modulating valve to the corresponding transmission clutch, as shown.
| |
| Illustration 3 | g01322698 |
|
Modulating Valves (Transmission) | |
Each modulating valve has a designated letter, as shown. The letters have been cast into the transmission housing.
Log the clutch pressures in Table 2. There are always two clutches that are engaged for each gear selection. NEUTRAL position only uses one clutch. See Table 2 in order to determine the clutches that are engaged for each gear selection.
| Checklist for Transmission Clutch Pressures | ||||
|---|---|---|---|---|
| Gear | Clutch or Valve | Pressure Measurement | Clutch or Valve | Pressure Measurement |
| Fourth gear (reverse) | A | J | ||
| Third gear (reverse) | A | H | ||
| Second gear (reverse) | A | B | ||
| First gear (reverse) | A | G | ||
| Neutral | J | - | - | |
| First gear | C | G | ||
| Second gear | D | G | ||
| Third gear | E | G | ||
| Fourth gear | F | G | ||
| Fifth gear | C | B | ||
| Sixth gear | C | H | ||
| Seventh gear | D | B | ||
| Eighth gear | D | H | ||
| Ninth gear | E | B | ||
| Tenth gear | E | H | ||
| Eleventh gear | F | B | ||
| Twelfth gear | F | H | ||
| Thirteenth gear | C | J | ||
| Fourteenth gear | D | J | ||
| Fifteenth gear | E | J | ||
| Sixteenth gear | F | J | ||
- Make sure that the transmission control lever is in the PARK position.
- Warm the oil to a minimum temperature of
60°C (140°F) .Third gear that uses clutches (E) and (G) is shown in the following test:
- Connect one end of Tooling (K) to the test port on valve (E). Connect one end of a second Tooling (K) to the test port on valve (G).
- Operate the transmission in third gear at high idle.
- Observe the pressure that is being delivered to transmission clutches (E) and (G). You can use Table 2 to write down the measurement.
- Stop the engine.
- Repeat Steps 3 through 6 for the remaining reverse gears and forward gears. Use Table 2 in order to determine the combination of modulating valves that are being engaged for each gear.
- Compare the pressure measurements from all of the transmission clutches. The pressure measurement should be within
2100 ± 35 kPa (305 ± 5 psi) . - Remove Tooling (K).
- Stop the engine.
- If the pressure is not within the specified limits, check the pressure that is being delivered by the relief valve (charge pressure).