BALL 0104920 - Caterpillar

Scraper Transmission Small Cover Location3. Remove small cover from scraper transmission case.4. Remove the plugs from P1 speed clutch pressure tap (F) and P2 directional clutch pressure tap (G) and install nipple assemblies.5. Connect a pressure gauge [4000 kPa (600 psi)] to the nipple assemblies.
Location Of Pressure Tap (F) and (G) (Large Cover Removed for Photographic Purpose) (F) Pressure tap for speed clutch (P1). (G) Pressure tap for directional clutch (P2).6. Turn the tractor disconnect and start switches ON. Do not start tractor engine.7. Start the scraper engine and move the tractor transmission rotary selector spool to the FIRST speed position.8. Stop the engine and let all pressures go to 0 kPa (0 psi).9. Start the scraper engine and run it at LOW IDLE rpm.10. The pressure at pressure tap P1 (F) must be 2413 kPa (350 psi) minimum. The pressure at pressure tap P2 (G) must be 0 kPa (0 psi)11. Move the tractor transmission rotary selector spool to the NEUTRAL position.12. The pressure at pressure tap P1 (F) must be an initial pressure of 621 97 kPa (90 14 psi). The pressure at pressure tap P2 (G) must be at 0 kPa (0 psi).13. With the scraper engine still running in LOW IDLE, shift the tractor transmission rotary selector spool to any speed position except NEUTRAL.14. The pressure at pressure tap P1 (F) must be 2413 kPa (350 psi) minimum. The pressure at pressure tap P2 (G) must be 345 55 kPa (50 8 psi) less than the pressure at P1.15. With the tractor transmission still in any speed except NEUTRAL, increase scraper engine rpm to HIGH IDLE.16. The pressure at pressure tap P1 (F) must be 2724 69 kPa (395 10 psi). The pressure at pressure tap P2 (G) must be 345 55 kPa (50 8 psi) less than the pressure at P1.17. When this test is complete, put the tractor transmission in NEUTRAL and stop the engine. If Test 6 is to be done, do not remove test equipment.
Pressure Control Valve Group
(7) Modulation relief valve. (8) Spacers. Problem:The oil pressure in Step 14 is too low. Probable Cause:* The setting of modulation relief valve (7) is too low. Add spacers (8), see spacer chart for modulation relief valve. Problem:The oil pressure in Step 14 is too high. Probable Cause:The setting of modulation relief valve (7) is too high. Remove spacers (8), see spacer chart for modulation relief valve. Problem:The pressure at P2 (F) is not correct throughout this test. Probable Cause:The combination valve is not working correctly. Test 6. Synchronizing Solenoid Pressure
This test will show if:* The synchronizing solenoid operates correctly.* The priority valve operates correctly.
Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To prevent possible injury, make reference to the warning and do the procedure at the start of Test 5 (testing of Speed and Directional Clutch pressures) before performing Test 6.
Procedure:1.