Challenger 35, Challenger 45 and Challenger 55 Agricultural Tractors Power Train Caterpillar

Illustration 1	g00637850
Test port location (A) Speed clutch (B) Speed clutch (C) Speed clutch (1) Number one speed clutch (2) Number two speed clutch (3) Number three speed clutch (F1) First direction clutch F1 (F2) Second forward direction clutch F2 (REV) Reverse direction clutch

Perform the following steps before you test the transmission pressure.

1. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level - Check".

2. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation/Testing and Adjusting, "Transmission Clutch Calibration".

3. Repair any problems that are found in the calibration procedure.

4. Check the transmission charge oil pressure. Refer to "Charge Pressure Tests for the Transmission".

5. Check the supply oil to each of the clutch solenoids in the transmission control valve.

6. Install one 3J-7354 O-Ring Seal on each of the 110-6349 Nipple Assemblies.

7. Install the 110-6349 Nipple Assemblies on the control valves for the six speed clutches.

8. Install the 110-6349 Nipple Assemblies on the control valves for the three direction clutches.

While you perform the transmission pressure tests, record the following pressures in Table 4.

• Clutch pressures for the 16 forward speed clutches

• Clutch pressures for the nine reverse speed clutches

• Directional clutch pressures

If the pressure of one clutch is low, check the other speeds that use the clutch. Hold a compass near the solenoid. Use the EMC in order to energize the solenoid. The needle of the compass should turn toward the solenoid. If the needle of the compass does not turn, refer to Systems Operation and Testing and Adjusting, RENR1781, "Electronic Systems". If the solenoid is working properly, inspect the seals on the solenoid valve. Replace any seals that appear to be leaking. Recalibrate the transmission after the repairs have been made. Refer to Testing and Adjusting, "Transmission Clutch Calibration".

Pressure Testing

Charge Pressure Test for the Transmission

1. Park the machine on a level surface. Stop the engine and apply the parking brake.

Show/hide table



Illustration 2	g00492672

2. Connect an 8T-0854 Pressure Gauge to the nipple assembly (7) on the bottom left side of the transmission control valve.

3. Start the engine. Warm the hydraulic oil to a temperature of 60°C (140.0°F). At least two segments should be visible on the bargraph for hydraulic oil temperature.

4. Start the engine. Adjust the engine speed to 2100 rpm. The pressure of the oil should be 1825 ± 70 kPa (265 ± 10 psi).

5. If the pressure reading is not correct, stop the engine. Then, reshim the pressure regulating valve.
   Show/hide table
   
   

   Illustration 3	g00637811

   1. Remove spring retaining cap (8) .

      Note: The springs are under pressure and the springs may escape when the spring retaining cap is removed.

   2. The spring retaining cap contains a large washer and the spring retaining cap contains shims for pressure adjustment. Add shims in order to increase the pressure. Remove shims in order to decrease the pressure.

   3. Recheck the charge pressure. If the charge pressure is not correct, repeat Step 4 through Step 5.b.

      Note: If the correct pressure can not be achieved, the pump should be inspected.

Individual Clutch Testing

The clutch pressures should be logged on Table 4. Three clutches should be engaged in each of the speed ranges. Refer to Table 5 in order to determine the clutches that are engaged in each speed.

Use the following procedure in order to test the pressures for the clutch engagement.

1. Park the machine on a level surface. Stop the engine and apply the parking brake.

2. Remove the plug and install a 3J-7354 O-Ring Seal and 110-6349 Nipple Assembly in each of the test ports.

   Note: The designation of the clutch is marked on the casting of the transmission valve.

3. Use Table 5 in order to determine the clutches that are engaged in each speed.

4. Install a 8T-0854 Pressure Gauge and install a line on each of the following test ports. (A), (1) and (F1) .

5. Start the engine. Warm the hydraulic oil to a temperature of 60°C (140.0°F). At least two segments should be visible on the bargraph for hydraulic oil temperature.

6. Operate the machine in the first forward speed.

7. Record the pressures from the gauges. Refer to Table 4.

8. Use this process for the remainder of the forward speeds and reverse speeds. Use Table 5 in order to determine the clutches that will be engaged for each of the gears.

9. Compare the pressure readings from all of the engaged clutches.
   • The clutch pressure should not vary more than ten percent.

   • If no pressure reading is recorded check the solenoid and the valve.

   • If there is a pressure reading on a clutch that is disengaged, check for the following conditions: internal leak between clutch packs, failure of an internal seal ring, internal leak in the housing for the transmission control and open solenoid valve.

   • If the pressure for the clutch is correct, the clutch pack may be worn.