Installation and Adjustment of 3161 Governor on 3500 Family of Engines{1264} Caterpillar

Introduction

The information in this instruction is for the on-engine adjustment of a 3161 Governor on the 3500 Family of Engines.

Specific tools that will be needed for the adjustment procedure are also given in a Tools Needed chart.

Tools Needed

Governor Preparation

Because of the clearance between the fuel control linkage cover and governor, the upper left side bolt at location (A) must be installed before the cover (1) is put on the terminal shaft, and before the governor is fastened to the drive adapter housing. The other bolts can be installed after the governor is positioned on the engine.

Install a new 2W9063 Washer and a new 4H1722 Seal (lip type) in the Fuel Control Linkage Cover.

Put clean engine oil on the lip of the seal, and install the cover over the governor terminal shaft.

There are two control levers for the 3161 Governor used on 3500 Engines. Lever (2) has a fixed pin and lever (3) has an adjustable pin. Lever (2), with the fixed pin, is used on the 3161 Generator Set and earlier Standard Governors.

Lever (3), with the adjustable pin, is used on 3161 Governors with fuel air ratio control adjustment and torque rise features. Lever (3) is used to synchronize governor fuel air ratio control adjustment and torque rise schedules to engine fuel zero reference position. Lever (3), with the adjustable pin, can be used on a right side or left side mounted commercial governor. To convert the lever from right side use to left side use, remove the lock bolt and lock from the adjustable pin.

Remove the adjustable pin from the lever, turn it around, and install it into the lever the opposite way. Install the lock and bolt into the adjustable pin and tighten just enough to hold in position. The lever can now be used on the other end of the terminal shaft for left side mounted governors.

The lever and pin (fixed or adjustable) connect the governor terminal shaft to the fuel control linkage stop lever. The lever pin moves in notch (4) of the stop lever. This causes the two to move together.

The 3161 Generator Set and earlier Standard Governors with fixed pin control levers do not require special adjustments when installed on the engine.

After fuel control linkage cover (1) is in position, install lever (2) on the governor terminal shaft. Tighten the bolt to a torque of 25 ± 7 N·m (18 ± 5 lb ft). Control levers can only be installed the correct way, because of the flat and groove of the terminal shaft and the lever pin.

This control lever is for right-side mounted governors. On control levers for left-side mounted governors, the pin is reversed.

For those 3161 Governors with fuel air ratio control adjustment and torque rise features, the adjustable pin control lever is installed on the terminal shaft. Bolt (5) is then tightened to a torque of 25 ± 7 N·m (18 ± 5 lb ft).

Before the governor is installed, tighten the pin lock bolt (6) so it will hold the pin in position when the governor is installed on the engine.

After the governor is installed on an engine, the adjustable pin is turned to synchronize the governor travel to the fuel control linkage. For correct adjustment and setting of these governors, refer the topic entitled Governor Installation in this publication.

Governor Installation

3161 Generator Set and Earlier Standard Governors

1. Make sure four O-ring seals (8), are in position on the governor drive housing. Install the seal on the governor oil pump housing. Put clean engine oil on all seals.

2. Put the governor and cover gasket in position. Make sure the governor drive shaft and the spline drive are in correct alignment. The pin on the governor lever must engage in the slot in the fuel control linkage stop lever.

Cover removed for illustrative purposes only.

NOTE: Be sure there is no binding, side load on the drive shaft, or looseness in the drive coupling. The maximum runout of the governor drive shaft and coupling must be less than 0.15 mm (0.006"). Parts that do not fit correctly or are not in alignment, can cause early wear, shaft seizure, or governor drive shaft failure.

3. Move the governor to put cover (1) in correct alignment (square) with the front housing of the engine. With the governor in alignment, install and tighten bolts (9) to hold the governor to the drive housing.

4. Put cover (1) against the front drive housing and make sure the gasket is in alignment. Install and tighten the bolts. Check the governor terminal shaft for free movement, refer to Step 6.

5. Install bracket (10) as follows:

* Install two bolts in the side of the governor.

* Slide bracket (10) in place on the bolts. Tighten the bolts enough to hold bracket (10) in position. The bracket must be free enough to move.

* Install and tighten the two bolts that hold bracket (10) to the top of cover (2). This puts the bracket in correct alignment.

* Tighten the two bolts that hold bracket (10) to the governor.

* Check the governor terminal shaft for free movement, refer to Step 6.

6. Move the governor terminal shaft several times in the "FUEL ON" direction, then release it. The terminal shaft must return completely to the "FUEL OFF" position each time. If the terminal shaft does not return, binding can be the result of parts not in correct alignment.

If the terminal shaft is binding, loosen the cover bolts, align the cover, then tighten the bolts. Again check for binding using the above procedure. If this does not correct the binding problem, loosen the bolts that fasten the governor base to the drive housing. Move the governor as necessary, and again tighten the bolts. Again check for binding using the above procedure.

NOTE: If the governor terminal shaft is binding after the above procedure, first loosen the bolts for the fuel control linkage cover, then loosen the bolts that hold the governor drive housing in position. Move the housing the amount necessary to get alignment of the cover bolt holes. Tighten all of the bolts, then check again for terminal shaft binding.

7. It is necessary to fill the governor with oil. Remove the oil fill plug (7) from the governor top cover. Add 1.8 liters (2 U.S. quarts) of clean engine oil to the governor before the first start up of the engine. Install and tighten the plug in the top cover.

3161 Governor With Fuel Air Ratio Control Adjustment - Governor to Engine Synchronization

1. Make sure four O-ring seals (8), are in position on the governor drive housing. Install the seal on the governor oil pump housing. Put clean engine oil on all seals.

2. Put the governor and cover gasket in position. Make sure the governor drive shaft and the spline drive are in correct alignment. The pin on the governor lever must engage in the slot in the fuel control linkage stop lever.

Cover removed for illustrative purposes only.

NOTE: Be sure there is no binding, side load on the drive shaft, or looseness in the drive coupling. The maximum runout of the governor drive shaft and coupling must be less than 0.15 mm (0.006"). Parts that do not fit correctly or are not in alignment, can cause early wear, shaft seizure, or governor drive shaft failure.

3. Move the governor to put cover (1) in correct alignment (square) with the front housing of the engine. With the governor in alignment, install and tighten bolts (9) to secure the governor to the drive housing.

4. Remove the plug from test ports (11) and (12).

5. Remove synchronizing pin (13) from the fuel setting cover. Remove the washer from the synchronizing pin. Install the synchronizing pin in test port (11). Tighten synchronizing pin (13) to a torque of 10 ± 2 N·m (90 ± 18 lb in).

Cat Vehicular Engines.

6. Install the 4C6101/4C6099 Terminal Shaft Torque Arm (14) on the terminal shaft and turn the shaft to a fully clockwise (CW) position.

The torque arm handle must point toward the center of the engine and be within ± 30° of horizontal when it is installed and turned clockwise (CW). Hold the shaft in position and hang 4C6103 Weight (15), [4.0 kg (9.0 lb)], on the hole in the handle of the arm.

The arm and weight are used to hold the terminal shaft of the governor in the full clockwise (CW) position. This puts the fuel control linkage stop lever against the end of the synchronizing pin. The 4C6101/4C6099 Terminal Shaft Torque Arm is to be attached only with the engine "shut down".

Commercial Engines.

7. Remove bolt (16) and manual fuel shutoff lever (17) (commercial engines only).

Commercial Engines.

8. Install FT1819 Governor Torque Arm (18) on the terminal shaft. The FT1819 Governor Torque Arm (18) is used to hold the terminal shaft of the governor in the full clockwise (CW) position. This puts the fuel control linkage stop lever against the end of the synchronizing pin. The FT1819 Governor Torque Arm (18) is to be attached only with the engine "shut down".

NOTE: On some applications, FT1819 Governor Torque Arm (18) can not be used. Move the governor output shaft in the "FUEL ON" direction by hand. Hold the governor output shaft and fuel control linkage against the synchronizing pin with a force of 10 N·m (90 lb in) to give an accurate dial indicator reading.

9. Install and zero the indicator. Either an 8T1000 Electronic Position Indicator Group, or, the 6V3075 Dial Indicator are acceptable for use. Installation instructions for both indicators are as follows:

* 8T1000 Electronic Position Indicator Group - Install the 5P4814 Collet in test port (12). Slide the 8T1002 Probe with the 5P7263 Contact Point into the 5P4814 Collet until 8T1002 Probe sleeve bottoms in the 5P4814 Collet. Tighten the collet enough to hold the probe in this position. Attach the probe to the 8T1001 Indicator. Turn the indicator ON and set it to measure millimeters. With the indicator ON, touch the zero button. The indicator is now ready to be used for the adjustment.

* 6V3075 Dial Indicator - Install the 5P4814 Collet in test port (12). Slide the 6V3075 Dial Indicator with the 5P7263 Contact Point into the 5P4814 Collet. When the contact point seats against the fuel stop lever, slide the indicator IN or OUT, until the indicator dial reads "ZERO". Tighten the collet enough to hold the indicator in this position. The indicator is now ready to be used for the adjustment.

10. Remove 4C6101/4C6099 Terminal Shaft Torque Arm (14) and 4C6103 Weight (15), or, FT1819 Governor Torque Arm (18) from the governor terminal shaft. Make sure the terminal shaft returns to the "FUEL OFF" position.

11. Loosen synchronizing pin (13) a minimum of 25.4 mm (1.00").

12. The rig pin (19) is used to stop the governor terminal shaft at a fixed position while setting the adjustable pin control lever, to synchronize governor travel with engine fuel control linkage travel.

NOTE: The rig pin (19) is to be used only with the engine "shut down".

Put a 5/32" hex wrench in the governor rig pin, push IN, then turn it counterclockwise until the roll pin locks squarely behind the bracket.

13. Install the 4C6101/4C6099 Terminal Shaft Torque Arm (14) and 4C6103 Weight (15), or, install FT1819 Governor Torque Arm (18) to turn and hold the governor terminal shaft and linkage against the governor rig pin.

14. With a 1/4" hex bit × 3/8" drive socket on a 305 mm (12.0") extension and ratchet, position the socket and extension between the cover and housing. Put the hex bit in the governor control lever pin lock bolt and loosen the bolt.

NOTE: Earlier pin lock bolts were a 1/2" standard bolt.

Move the ratchet and extension UP or DOWN until the dial indicator reads 0 ± 0.00 mm (0 ± 0.000") while the terminal shaft is held in the "FUEL ON" direction against the governor rig pin.

Tighten the pin lock bolt (6) on the governor control arm to 25 ± 7 N·m (18 ± 5 lb ft) of torque.

Move the terminal shaft torque arm tool to the "FUEL OFF" position and return it so it is against the governor rig pin. The dial indicator must return to zero each time. If it does not, do the above procedure again.

15. Remove the terminal shaft torque arm tool from the governor terminal shaft.

16. Release the governor rig pin (19). Push on the hex wrench and turn it clockwise (CW) until the roll pin unlocks from the bracket. Release the hex wrench and the spring will return the pin to the disengaged position. Remove the hex wrench.

17. Turn the synchronizing pin (13) IN all the way, and tighten it to 10 ± 2 N·m (90 ± 18 lb in) of torque. Install the terminal shaft torque arm to hold the fuel control linkage stop lever against synchronizing pin. Refer to Step 6. Without a change to the dial indicator position, make sure the reading is zero to indicate the correct fuel control linkage dimension.

18. Remove 8T1002 Probe or 6V3075 Dial Indicator and 5P4814 Collet from test port (12).

19. Remove synchronizing pin (13) from test port (11). Install the washer on synchronizing pin (13) and install the synchronizing pin in the fuel setting cover.

20. Install the test port plugs in test ports (11) and (12).

21. Put cover (1) against the front drive housing and make sure the gasket is in alignment. Install and tighten the bolts. Check the governor terminal shaft for free movement, refer to Step 23.

22. Install bracket (10) as follows:

* Install two bolts in the side of the governor.

* Slide bracket (10) in place on the bolts. Tighten the bolts just enough to hold the bracket in position, however, the bolts must be loose enough to permit the bracket to move.

* Install and tighten the two bolts that hold bracket (10) to the top of cover (1). This puts bracket (10) in correct alignment.

* Tighten the two bolts that hold bracket (10) to the governor.

* Check the governor terminal shaft for free movement, refer to Step 23.

23. Move the governor terminal shaft in the "FUEL ON" direction several times, then release it. The terminal shaft must return to the "FUEL OFF" position completely, each time it is released. If the terminal shaft does not return as required, it can be caused by parts that are binding and not in correct alignment.

If the terminal shaft is binding, loosen the cover bolts, realign the cover and tighten the bolts. Again check for binding with the above procedure. If this does not correct the binding problem, loosen the bolts that fasten the governor base to the drive housing. Move the governor as necessary and again tighten the bolts. Again check for binding using the above procedure.

NOTE: If the governor terminal shaft is binding after the above procedure, first loosen the bolts for the fuel control linkage cover, then loosen the bolts that hold the governor drive housing in position. Move the housing as necessary to get alignment of the cover bolt holes. Tighten all of the bolts, then again check for terminal shaft binding.

24. It is necessary to fill the governor with oil. Remove the oil fill plug (7) from the governor top cover. Add 1.8 liter (2 U.S. quarts) of clean engine oil to the governor before the first start up of the engine. Install and tighten the plug in the top cover.

Fuel Air Ratio Control Adjustment

There are two adjustments for the fuel ratio control. One adjustment is the fuel limit adjustment, and the other adjustment is a gain rate that is factory set, and must not be changed.

Check and Adjustment Of Fuel Limiter

1. For the correct fuel ratio control setting dimension, refer to the topic entitled "Dynamic Fuel Settings" in the "Fuel Setting and Related Information" microfiche library (SBFY1109).

2. Remove the plug from test ports (11) and (12).

3. Remove synchronizing pin (13) from the fuel setting cover. Remove the washer from the synchronizing pin. Install synchronizing pin in test port (11). Tighten synchronizing pin (13) to a torque of 10 ± 2 N·m (90 ± 18 lb in).

Cat Vehicular Engines.

4. Install the 4C6101/4C6099 Terminal Shaft Torque Arm (14) on the terminal shaft and turn the shaft to a fully clockwise (CW) position. The Torque Arm handle must point toward the center of the engine and be within ± 30° horizontal when it is installed and turned clockwise (CW). Hold the shaft in position and hang 4C6103 Weight (15), [4.0 kg (9.0 lb)] on the hole in the handle of the arm.

The arm and weight are used to hold the terminal shaft of the governor in the full clockwise (CW) position. This puts the fuel control linkage stop lever against the end of the synchronizing pin. The 4C6101/4C6099 Terminal Shaft Torque Arm is to be attached only with the engine "shut down".

Commercial Engine.

5. Install FT1819 Governor Torque Arm (18) on the terminal shaft. The FT1819 Governor Torque Arm (18) is used to hold the terminal shaft of the governor in the full clockwise (CW) position. This puts the fuel control linkage stop lever against the end of the synchronizing pin. The FT1819 Governor Torque Arm (18) is to be attached only with the engine "shut down".

NOTE: On some commercial applications, FT1819 Governor Torque Arm (18) can not be used. Move the governor output shaft in the "FUEL ON" direction by hand. Hold the governor output shaft and fuel control linkage against the synchronizing pin with a force of 10 N·m (90 lb in) to give an accurate dial indicator setting.

6. Install and zero the indicator. Either an 8T1000 Electronic Position Indicator Group, or, the 6V3075 Dial Indicator are acceptable to use. Installation instructions for both indicators are as follows:

* 8T1000 Electronic Position Indicator Group - Install the 5P4814 Collet in test port (12). Slide the 8T1002 Probe with the 5P7263 Contact Point into the 5P4814 Collet until 8T1002 Probe sleeve bottoms in the 5P4814 Collet. Tighten the collet enough to hold the probe in this position. Attach the probe to the 8T1001 Indicator. Turn the indicator ON and set it to measure millimeters. With the indicator ON, touch the zero button. The indicator is now ready to be used for the adjustments.

* 6V3075 Dial Indicator - Install the 5P4814 Collet in test port (12). Slide the 6V3075 Dial Indicator with the 5P7263 Contact Point into the 5P4814 Collet. When the contact point seats against the fuel stop lever, slide the indicator IN or OUT, until the indicator dial roads "ZERO". Tighten the collet enough to hold the indicator in this position. The indicator is now ready to be used for the adjustment.

7. Remove 4C6101/4C6099 Terminal Shaft Torque Arm and 4C6103 Weight, or, FT1819 Governor Torque Arm (18) from the governor terminal shaft. Make sure the terminal shaft returns to the "FUEL OFF" position.

8. Disconnect the boost line from the fuel ratio control. Plug the boost line to keep dirt and foreign material out of the engine.

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Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

9. Start the engine.

10. Rapidly move the speed control shaft in the speed increase direction. The rack position indicator will go up to the fuel limit position, pausing momentarily at this position as the engine accelerates to Hi Idle and then drops back to the idle rack position as the engine speed reaches High Idle. Repeat this procedure several times and read the rack position indicator during each pause.

At the point where the rack position indicator pauses is the limit for fuel control linkage movement set by the fuel ratio control. If the fuel limit setting is in need of adjustment, proceed to Step 11. If the fuel limit setting is correct, stop the engine and proceed to Step 13.

11. Remove plug (20) from the right front corner of the top cover. Put a 3/16" hex wrench through the hole in the top cover until it engages the adjustment screw. Rapidly move the speed control shaft in the speed increase direction. The rack position indicator will go up to the fuel limit position, pausing momentarily at this position as the engine accelerates to Hi Idle and then drops back to the idle rack position as the engine speed reaches High Idle.

During the momentary pause, turn the limit adjustment screw until the dimension on the rack position indicator is the same as the specifications given in the "Fuel Setting and Related Information" microfiche library (SBFY1109).

Turning the limit adjustment screw clockwise (CW) will decrease the limiter setting, while turning the limit adjustment screw counterclockwise (CCW) will increase the limiter setting.

12. When the adjustment is correct, stop the engine. Remove the hex wrench and install the plug in the top cover. Put a seal wire through the holes in both the plug and the bolt head. Install the governor seal. Remove the plug from the boost line. Connect the boost line from the inlet manifold to the fuel ratio control.

13. Remove 8T1002 Probe or 6V3075 Dial Indicator and the 5P4814 Collet from test port (12).

14. Remove synchronizing pin from test port (11). Install the washer on the synchronizing pin and install the synchronizing pin in the fuel setting cover.

15. Install the plugs in test ports (11) and (12).

Torque Rise Setting Procedure

Governors with Single or Dual Slope Torque Rise Springs

The D11N has a single slope torque rise governor. The 776B, 777B, 785, and 789 all have dual slope torque rise governors.

1. Synchronize the governor to the engine.

2. Refer to the "STATIC FUEL-SETTINGS" in the "Fuel Setting and Related Information" microfiche library (SBFY1109) to find the correct settings for the FULL LOAD breakpoint and FULL TORQUE setting.

In the past "STATIC FUEL SETTING" was listed in the "Fuel Setting and Related Information" microfiche for the 3500 Engines. This fuel setting was "MAXIMUM RACK TRAVEL" and was listed as "STATIC FUEL SETTING".

For those 3500 Engines equipped with a 3161 Generator Set Governor, or an earlier Standard Governor, the fuel setting procedure has not changed. The fuel setting screw is used to set the "MAXIMUM RACK TRAVEL", but, the specification in the FUEL SETTING AND RELATED INFORMATION microfiche is shown as "FULL LOAD". "FULL LOAD" and "FULL TORQUE" dimensions will be the same number.

For those 3500 Engines equipped with 3161 Governors that have a single or dual slope torque rise, there are two static fuel dimensions. The first dimension is "FULL TORQUE", which is maximum rack travel, and is set with the fuel setting screw. The second dimension is "FULL LOAD", which is a "reference position" where the fuel control linkage is held, while the torque rise spring is adjusted. This is a temporary dimension, set with the synchronizing pin. This dimension is shown in the FUEL SETTING AND RELATED INFORMATION microfiche as "FULL LOAD."

The dual slope torque rise governor has an additional dimension "first breakpoint". This "first breakpoint" dimension is 5.43 mm (0.214") less than the "FULL LOAD" dimension. This is also a temporary dimension that is set with the synchronizing pin. This dimension is NOT shown in the FUEL SETTING AND RELATED INFORMATION microfiche.

Altitude Deration

Refer to ALTITUDE DERATING DATA under the STATIC FUEL-SETTINGS in the FUEL SETTING AND RELATED INFORMATION microfiche to find the correct dimension for the FULL LOAD breakpoint and FULL TORQUE, for operation at a specific altitude. On dual slope torque rise governors the "first breakpoint" will be 5.43 mm (0.214") less than the "full load" dimension in all altitude ranges.

NOTE: Before removing the top cover of the governor, make sure that the entire area surrounding the governor is free from dirt and debris. A high pressure wash is recommended to clean the governor and governor area before adjustment.

3. Remove plugs from test ports (11) and (12).

4. Remove synchronizing pin (13) from the fuel setting cover. Remove the washer from the synchronizing pin. Install the synchronizing pin in test port (14). Tighten synchronizing pin (13) to a torque of 10 ± 2 N·m (90 ± 18 lb in).

5. Remove bolts (21) that hold the top cover in position on the governor. Make sure that the oil level of the governor is below the joint face of the top cover and the governor housing. This will eliminate the loss of oil due to spillage.

Remove top cover (22) and gasket (23).

6. Install the 4C6101/4C6099 Terminal Shaft Torque Arm (14) on the terminal shaft and turn the shaft to a fully clockwise (CW) position.

The Terminal Shaft Torque Arm handle must point toward the center of the engine and be within ± 30° horizontal when it is installed and turned clockwise (CW). Hold the shaft in position and hang the 4C6103 Weight [4.0 kg (9.0 lb)] (15) on the hole in the handle of the arm.

The arm and weight are used to hold the terminal shaft of the governor in the full clockwise (CW) position. This puts the fuel control linkage stop lever against the end of the synchronizing pin.

7. Install the 4C6098 Speeder Shaft Torque Arm (24) on the speeder shaft and turn the shaft clockwise (CW) to a full throttle position.

The torque arm handle must point toward the radiator and be within ± 30° of horizontal when it is installed and turned clockwise (CW). Hold the shaft in position and hang 4C6102 Weight (25), [2.3 kg (5.0 lb)] on the hole in the handle of arm. The arm and weight are used to hold the throttle (speeder shaft) in the "FULL ON" position.

NOTE: The use of the Torque Arms and Weights, puts the fuel control linkage in position for adjustment. DO NOT OPERATE THE ENGINE WITH THESE TOOLS ON THE GOVERNOR. THE TOOLS ARE DESIGNED FOR ADJUSTMENT PURPOSES ONLY.

8. Install and zero the indicator. Either an 8T1000 Electronic Position Indicator Group, or, the 6V3075 Dial Indicator are acceptable to use. Installation instructions for both indicators are as follows:

* 8T100 Electronic Position Indicator Group - Install the 5P4814 Collet in test port (12). Slide the 8T1002 Probe with the 5P7263 Contact Point into the 5P4814 Collet until 8T1002 Probe sleeve bottoms in the 5P4814 Collet. Tighten the collet enough to hold the probe in this position. Attach the probe to the 8T1001 Indicator. Turn the indicator ON and set it to measure millimeters. With the indicator ON, touch the zero button. The indicator is now ready to be used for the adjustment.

* 6V3075 Dial Indicator - Install the 5P4814 Collet in test port (12). Slide the 6V3075 Dial Indicator with the 5P7263 Contact Point into the 5P4814 Collet. When the contact point seats against the fuel stop lever, slide the indicator IN or OUT, until the indicator dial reads "ZERO". Tighten the collet enough to hold the indicator in this position. The indicator is now ready to be used for the adjustment.

9. Use a 3/32" hex wrench to turn null screw (26), on the governor torque control group, in a clockwise (CW) direction until it stops. This positions the pilot valve to the static adjust/test position for torque control setting screws.

NOTE: Clean screw balls, pads and control spring sides (27) with solvent to insure electrical contact while testing.

NOTE: Steps 10 and 11 do not apply to single slope torque rise governors. Proceed to Step 12 when adjusting a single slope torque rise governor.

10. Loosen the synchronizing pin until the dimension for the "first breakpoint" setting is read on the indicator.

Apply a slight amount of pressure (tapping) on the 4C6099 Terminal Shaft Torque Arm (14) and 4C6103 Weight (15), to make sure the fuel stop lever is solidly against the synchronizing pin.

11. Connect the clip end of the 8T0500 Circuit Tester (28) to the governor case-to-cover bolt hole. Touch the probe end of the circuit tester to the edge of the first spring (top leaf spring) in sandwich portion of the control group.

NOTE: Do not touch the probe end to the top surface of the leaf spring because the oxide film will cause faulty continuity readings.

Use a 3/32" hex wrench to turn top leaf spring adjustment screw (29). Turn adjustment screw (29) in a clockwise (CW) direction until the circuit tester light just comes on (a dim light). If the circuit tester light is already lit, turn the adjustment screw (29) counterclockwise (CCW) until light goes off and then turn the adjustment screw clockwise (CW) until light is dimly lit.

12. Loosen the synchronizing pin (13) until the "FULL LOAD" dimension is read on the indicator.

Apply a slight downward "tapping" pressure on the 4C6099 Terminal Shaft Torque Arm (14) and 4C6103 Weight (15), to insure that the fuel stop lever is solidly against the synchronization pin (13).

13. Connect the clip end of the 8T0500 Circuit Tester (28) to the governor case-to-cover bolt hole. Touch the probe end of the circuit tester to the edge of the bottom leaf spring in sandwich portion of the control.

NOTE: Do not touch the probe end to the top surface of the leaf spring because the oxide film will cause faulty continuity readings.

On single slope torque rise governors there is only one spring.

Use a 3/32" hex wrench to turn bottom leaf spring adjustment screw (30). Turn adjustment screw (30) in a clockwise (CW) direction until the circuit tester light just comes on (a dim light). If the circuit tester light is already lit, turn the adjustment screw (30) counterclockwise (CCW) until light goes off and then turn the adjustment screw clockwise (CW) until light is dimly lit. Single slope torque rise governors have only one adjustment screw.

14. Use a 3/32" hex wrench to turn null screw (26), on the governor torque control group, in a counterclockwise (CCW) direction until it stops. This releases the torque control pivot (pilot valve) to the run position.

NOTE: Null screw (26) must be in the run position before installation of the top cover and running the engine. Failure to return the screw to the run position will result in failure to start, erratic operation of the engine and failure to accept a load.

15. Loosen the synchronizing pin (13) and back it out a minimum of 25.4 mm (1.00"). Apply a slight downward pressure on the 4C6101/4C6099 Terminal Shaft Torque Arm (14) and 4C6103 Weight (15). The dimension on the indicator should be equal to the "FULL TORQUE" setting.

If adjustment is necessary, refer to the topic entitled Fuel Setting Adjustment in the "Testing and Adjusting" section of the Service Manual for the adjustment procedure.

16. Install the top cover (22) with a new gasket (23) on the governor. Install bolts (21) and tighten them to a torque of 10 ± 2 N·m (90 ± 18 lb in). After the top cover is installed, put a seal wire through the holes in both the plug and the bolt head. Install the governor seal.

17. Remove the 8T1002 Probe or the 6V3075 Dial Indicator and 5P4814 Collet from test port (12).

18. Remove synchronizing pin (13) from test port (11). Install the washer on the synchronizing pin, then install the synchronizing pin in the fuel setting cover.

19. Install the test port plugs in test ports (11) and (12).