3114, 3116 and 3126 MUI Engine Governors Caterpillar

The following procedures are used in order to adjust Type IV and some Type III governors after the governors have been assembled. There are certain governor adjustments that must be performed during governor assembly. Refer to the Disassembly and Assembly, "Governor (Type) - Assemble" section in this manual.

1. Install the governor on the 1U-7326 Governor Calibration Bench. Refer to the Testing and Adjusting, "Installation of Governor on 1U-7326 Governor Calibration Bench " section in this manual.

2. Verify the position of the throttle lever. Refer to the Testing and Adjusting, "Throttle Lever Orientation (Types IV, V, VI, VII, And Some III) - Check" section of this manual for more information.

3. If the throttle lever was positioned properly, proceed with Step 4. If the throttle lever was not positioned properly, refer to the Testing and Adjusting, "Throttle Lever (Types IV, V, VI, VII, And Some III) - Remove" and Testing and Adjusting, "Throttle Lever (Types IV, V, VI, VII, And Some III) - Install" sections in this manual for more information.

   Note: If the governor is equipped with a fuel ratio control, a regulated air supply of 140 to 210 kPa (20 to 30 psi) must be connected to the fuel ratio control during the adjusting procedure (except as noted during the fuel ratio control setting steps).

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Illustration 1	g00780280
(A) Access hole for the load stop adjustment screw and the fuel ratio adjustment screw

4. Remove the plug from access hole (A). To remove the plug, use a hammer and a punch to pierce the center of the plug. Then use a suitable prybar to remove the plug from the access hole.

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Illustration 2	g00660334

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Illustration 3	g00660348
(1) Spring (2) Throttle stop adjustment screw (3) Low idle adjustment screw (4) Load stop adjustment screw

5. Make sure that low idle adjustment screw (3) and throttle stop adjustment screw (2) are backed out so the end of the screw is not extending past the housing face.

   Connect spring (1) to the test bench and to the throttle in order to hold the throttle against the throttle stop.

6. Use a 1U-6672 Rack Adjusting Wrench to loosen load stop adjustment screw (4). Loosen the load stop adjustment screw until the end of the screw is even with the face of the governor housing.

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Illustration 4	g00660344
(5) Tachometer (6) Speed control knob

7. Connect the test bench to an electrical outlet. Turn on tachometer (5) .

8. Turn the switch for the test bench to the ON position.

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NOTICE
Do not turn the speed control knob unless the test bench is running. Damage to the variable speed drive may result. Except in the event of an emergency, the speed control knob should always be returned to the slowest rpm setting before the calibration bench is turned off.

9. Turn speed control knob (6) in the counterclockwise (CCW) direction to the slowest speed. Check all fluid connections for leaks. If leaks are found, perform any necessary repairs.

   Note: Always approach a specified rpm setting from a minimum of 100 rpm above the rpm that is required. This will ensure that the test readings are consistent for the entire test procedure.

   Note: All specifications for the governor adjustment procedure are in the Technical Marketing Information (TMI). If no values are listed in the specifications for a particular functional test, proceed to the next step in the test.

Note: If any of the adjustments for the function checks cannot be performed during the governor setting procedure, stop the procedure and inspect the governor for possible problems.

Note: The tolerances that are found in the TMI, refer to the Specifications, "Governor Performance Data" section in this manual, are applicable to all of the governor adjustments. The Expanded Tolerance Band that is referred to in the governor checking procedure is applicable to rechecking a governor that has been previously adjusted.

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Illustration 5	g00660334

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Illustration 6	g00660348
(1) Spring (2) Throttle stop adjustment screw (3) Low idle adjustment screw (4) Load stop adjustment screw

10. Adjust the speed on the calibration bench to the "LOAD STOP ADJ" rpm that is specified in the TMI. Adjust load stop adjustment screw (4) to the output dimension that is specified in the TMI.

11. Tighten the locknut for load stop adjustment screw (4) and check the output dimension again.

12. Increase the speed on the calibration bench by at least 100 rpm. Reduce the speed on the calibration bench back to the "LOAD STOP ADJ" rpm that is specified in the TMI. Check the output dimension again.

    If the dimension is not within the "RECHECK TOL" that is specified in the TMI, repeat Step 10.

13. Adjust the speed on the calibration bench to the "FUNC CHECK #1" rpm that is specified in the TMI. The output dimension must be a maximum of 0.0 mm (0.00 inch).

14. Adjust the speed on the calibration bench to the "THROT STOP ADJ" rpm that is specified in the TMI. Adjust throttle stop adjustment screw (2) in order to obtain the output dimension for the "THROT STOP ADJ". Tighten the locknut for throttle stop adjustment screw (2) and check the output dimension again.

15. Increase the speed on the calibration bench by a minimum of 100 rpm. Then reduce the speed back to the original "THROT STOP ADJ" rpm. Check the output dimension again. If the output dimension is not within the specification that is specified in the TMI, repeat Step 14.

16. Adjust the speed on the calibration bench to the "FUNC CHECK #2" rpm that is specified in the TMI. The output dimension must be within specifications. If the output dimension is not within specifications, repeat steps 10 through 16.

17. Adjust the speed on the calibration bench to the "FUNC CHECK #3" rpm that is specified in the TMI. The output dimension must be within specifications. If the output dimension is not within specifications, inspect the torque cam for wear or damage. Make sure that the correct torque cam is installed on the governor. If the torque cam needs to be replaced, refer to the Disassembly and Assembly, "Governor (Type) - Disassemble" and Disassembly and Assembly, "Governor (Type) - Assemble" sections in this manual.

    Note: If the governor is not equipped with a fuel ratio control, proceed to Step 21. If the governor is equipped with a fuel ratio control, continue with Step 18.

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Illustration 7	g00660400
(7) Fuel ratio control adjustment screw

18. If the governor is equipped with a fuel ratio control, purge the air pressure to the fuel ratio control. Adjust the speed on the calibration bench to the "FRC ADJ" rpm that is specified in the TMI. Adjust fuel ratio control adjustment screw (7) in order to obtain the dimension that is specified. Tighten the locknut for fuel ratio control adjustment screw (7) .

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NOTICE
A regulated air supply of 140 to 210 kPa (20 to 30 psi) must be used to avoid damage to the fuel ratio control.

19. Apply regulated air pressure to the fuel ratio control for approximately three seconds. Purge the air pressure. Snap the throttle lever to the throttle stop and back to the low idle position. Hold the throttle lever at the low idle position for approximately three seconds. Return the throttle lever to the throttle stop and check the output dimension for the "FRC ADJ". If the output dimension is not within the specification that is given in the TMI, adjust the output dimension and repeat this Step.

20. For the remainder of the test, the air supply to the fuel ratio control must be on.

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Illustration 8	g00780296
(B) Fuel transfer pump outlet (1) Spring (2) Throttle stop adjustment screw (3) Low idle adjustment screw (8) Pressure gauge (9) Inlet line

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Illustration 9	g00780280
(A) Access hole for the load stop adjustment screw and the fuel ratio adjustment screw

21. Remove spring (1) that connects the throttle lever to the base of the tachometer. This will permit the throttle lever to contact the governor housing in the low idle position.

22. Adjust the speed on the calibration bench to the "LOW IDLE ADJ" rpm that is specified in the TMI. Adjust low idle adjustment screw (3) in order to obtain the output dimension that is specified in the TMI. Tighten the locknut and check the output dimension again.

23. Increase the speed on the calibration bench by at least 100 rpm. Reduce the speed on the calibration bench back to the original "LOW IDLE ADJ" rpm. Check the low idle output dimension again.

    If the dimension is not within specifications, perform Step 22 again.

24. Adjust the speed on the calibration bench to the "FUNC CHECK #4" rpm that is specified in the TMI, if necessary. The output dimension must be within the tolerance that is specified in the TMI.

25. Reduce the speed on the calibration bench to the lowest setting and turn the switch to the OFF position.

26. If the fuel transfer pump was removed at the beginning of this procedure, install the fuel transfer pump on the governor housing and connect inlet line (9). Remove pressure gauge (8) from the quick disconnect fitting that is located on the housing for the lubrication filter. Install the pressure gauge on the quick disconnect fitting that is located at fuel transfer pump outlet (B). It is now possible to measure the fuel transfer pump pressure.

27. Turn the switch on the test bench to the ON position.

28. Adjust the speed on the calibration bench to 1500 rpm. The fuel transfer pump pressure should be 105 ± 30 kPa (15 ± 4 psi).

29. Reduce the speed on the calibration bench to the lowest rpm setting. Turn the switch on the test bench to the OFF position. The tachometer will turn OFF automatically after a short period of time.

30. After the test procedure is completed, install a new 7C-6204 Plug or the threaded plug in access hole (A) .

Note: When you apply 5P-3413 Pipe Sealant to the plug, ensure that pipe sealant does not enter the governor housing.

31. Use the following procedure to install the plug:
    • Ensure that the bore for the plug in the governor housing is clean and free of burrs.

    • Apply 5P-3413 Pipe Sealant around the edge of the plug. Then position the plug in the plug bore in the governor housing.

    • Use a hammer and a punch with a blunt end to carefully tap the plug in the center in order to expand the plug so that the plug is tight within the bore.

32. After the governor has been Installed on the engine and the low idle has been adjusted, seal the throttle adjustment screw with the lockwire and a tamper resistant seal.