ROD 9T2144 - Caterpillar

Adjusting the Governor
Any mechanic attempting make adjustments to the set point rpm should be trained in governor adjustment.
Engine rpm must be checked with an accurate tachometer. Refer to Testing and Adjusting, "Engine Speed - Check".Low Idle Adjustment
Note: Refer to Technical Marketing Information (TMI) for the correct low idle setting.Start the engine and run until the temperature of normal operation is reached. Check low idle rpm with no load on the engine. If an adjustment is necessary, use the procedure that follows:
Remove the sealed cover over the high idle adjustment screw and the low idle adjustment screw.
Illustration 1 g01029132
Idle adjustment (typical example) (1) High idle adjustment screw (2) Low idle adjustment screw (3) Tachometer drive
To adjust the low idle rpm, move the governor control to the low idle position and turn adjustment screw (2). Increase the engine speed and then return the control back to the low idle position in order to recheck the setting.
When governor adjustment is correct, install the cover over the adjustment screws.When the cover is installed on the governor, the idle adjustment screws fit into holes in the cover. The shape of the holes will not allow the idle adjustment screws to turn after the idle adjustment is done and the cover is installed.
Install a new wire and seal to the cover bolt.Checking the Set Point of the Engine (Balance Point)
The set point of the engine must be adjusted to specifications in order for correct operation of the engine. High idle rpm is not an adjusted specification. The set point of the engine (balance point) is full load rpm plus an additional 20 rpm. The set point is the rpm at which the fuel setting adjustment screw and the stop (or the first torque spring) begin to make contact. At this rpm, movement can be felt between the fuel setting adjustment screw and the stop (first torque spring). When additional load is placed on the engine, the fuel setting adjustment screw and the stop (first torque spring) will become stable against each other. The set point of the engine is controlled by the fuel setting and the high idle adjustment screw.
Table 1
Required Tools    
Part
Number    Part Description    Qty    
8T-0500     Continuity Test Light     1    
9U-7400     Multitach Tool Gp     1    
Illustration 2 g00300249
9U-7400 Multitach The 9U-7400 Multitach Tool Gp is used to check the set point. Refer to Tool Operating Manual, NEHS0605 for instructions on using this tool group. Note: Do not use the tachometer unless the tool's accuracy is known to be within 1 rpm.If the set point is correct and the high idle speed is within specifications, the fuel system operation of the engine is correct. The set point of the engine can be summarized by the following characteristics:
The setpoint is found at full load speed plus an additional 20 rpm.
Contact is made between the fuel setting adjustment screw and the stop (first torque spring).Use the procedure that follows to check the set point. Refer to