Kohler 38RCL Generator Set

Tools: digital voltmeter, personal computer, SiteTech software

1. Connect PC to controller via USB
2. With generator off, connect multimeter across L1/L2 (AC volts)
3. Start generator set
4. Compare voltmeter reading to controller display
5. Calculate new Genset Calibration Factor Voltage using (Vmeter / Vcontrol) x Fold = Fnew
6. Enter new value into SiteTech and click Apply Changes
7. Verify voltmeter matches controller display
8. Repeat for L2-L3 and L3-L1 if three-phase
9. Press OFF to stop generator set

Tools: digital voltmeter

1. With generator off, connect digital multimeter across L1 and L2, set to AC volts
2. Start generator set with RUN button
3. Navigate to Generator Metering menu, press Select; Volts L1-L2 displayed
4. Press Select; voltage number flashes
5. Use up/down arrows to match voltmeter reading
6. Press Select to confirm
7. Step to Return screen
8. Press OFF to stop generator set

Tools: clamp-on DC current probe or DC current meter

1. Connect DC current probe/clamp meter to measure generator current
2. Start generator with RUN button
3. Adjust system voltage to obtain rated current output with battery bank attached (or use load bank)
4. Trip output breaker
5. Navigate to Generator Metering menu, select Generator Load
6. Press and hold Select for No-Load Calibration; verify breaker open, confirm Yes
7. Close output breaker; verify rated output current, confirm Yes
8. Verify displayed load is correct; recalibrate if necessary
9. Press OFF to stop generator set

⚠ Always identify and correct the cause of a fault shutdown before resetting the controller.

1. Press the Select button to go to the Overview menu.
2. Press Select again to display the active fault.
3. Press Select; Confirm Clear Fault: NO is displayed.
4. Press the Up arrow button; Confirm Clear Fault: YES is displayed.
5. Press the Select button to enter YES and clear the fault.
6. Press the Select button to return to the overview menu.
7. Press AUTO to put the generator set into automatic mode.

⚠ Block heater damage. The block heater will fail if the energized heater element is not immersed in coolant. Fill the cooling system before turning on the block heater.

⚠ Do not add coolant to a hot engine. Wait until the engine has cooled.

⚠ Hot coolant and steam. Stop the generator set and allow it to cool before removing the pressure cap.

Tools: pipe sealant, cable tie

1. Secure the block heater to the block heater mounting bracket (GM78546) using 4 screws (M933-06020-60), 4 washers (M125A-06-80), and 4 hex nuts (M6923-06-80).
2. Secure the mounting bracket with block heater to the skid using 2 screws (M933-06016-60) and 2 hex nuts (M6923-06-80).
3. Locate the 2 shutoff valves on opposite sides of the engine block and verify they are closed.
4. Remove the pipe plug from each shutoff valve and discard the plugs.
5. Apply pipe sealant to the threads of hose connectors X-391-19 and X-582-1.
6. Install the 90 degree hose connector (X-391-19) in the shutoff valve closest to the block heater.
7. Install the straight connector (X-582-1) in the shutoff valve on the opposite side of the engine.
8. Hold the molded hose (276206 or GM103656) in place and cut to fit if necessary.
9. Install the shorter heat shield (GM17809) over the molded hose and secure with a cable tie.
10. Connect the molded hose to the hose connector and secure with a hose clamp (X-426-12 or GM103203).
11. Connect the other end of the hose to the block heater outlet and secure with a hose clamp (X-426-12 or GM103203).
12. Install the longer heat shield (GM23718) over the inlet hose (X-312-53 or X-312-47) and secure with a cable tie.
13. Connect the hose to the block heater inlet with a hose clamp (X-426-12); route the hose under the engine.
14. Secure the hang tag (279047) to the power cord.
15. Open the two block heater shutoff valves and, after the block heater is full, add approximately 0.6 L (0.2 gal) coolant to the cooling system.

1. Disable set: press OFF button, disconnect battery charger power, remove battery cables, negative (--) lead first.
2. Loosen the cover retaining knob(s) or release the retaining clips and remove the cover.
3. Remove and discard the old air cleaner element and precleaner (if equipped).
4. Install the precleaner over the new air cleaner element.
5. Install the paper element onto the air cleaner base, making sure it is flat and properly seated.
6. Reinstall the element cover, element cover nut, and the air cleaner cover; secure with the knob(s) or clips.
7. 15RES/30RES and RCL models: wipe cover and housing with a clean rag and make sure sealing surfaces fit correctly.
8. Reconnect the battery cable, negative (--) lead last.

⚠ Do not clean the element in any liquid or use compressed air; this will damage the filter element.

1. Remove the cover from the air cleaner housing.
2. Remove the air cleaner element.
3. Examine the element and housing for damage; replace if damaged.
4. Tap the element lightly against a flat surface to dislodge loose surface dirt.
5. Wipe the cover and housing with a clean rag to remove dirt.
6. Replace the air cleaner cover.

⚠ Do not load RDC2.4 firmware onto a red- or green-board controller

Tools: personal computer, USB cable, SiteTech software

1. Download latest firmware file (.bin) from Kohler Power Resource Center or dealer portal
2. Connect controller to PC via USB cable
3. Start SiteTech; program recognizes connected device
4. Click Update Firmware
5. Browse to and select firmware file, click Open
6. Verify current/new version and file name, click Update Firmware
7. Wait for 'Firmware Updated Successfully' message, click Close

⚠ Dispose of waste materials (oil, fuel, filter) in an environmentally safe manner.

Tools: oil filter wrench, drain hose

1. Press the OFF button on the RDC2 generator set controller.
2. Disconnect the power for the battery charger.
3. Disconnect the generator set engine starting battery, negative lead first.
4. Remove the housing side panel.
5. Remove the plug from the oil drain fitting and install a drain hose.
6. Open the oil drain valve on the engine and allow oil to drain completely.
7. Close the oil drain valve and replace the oil drain plug.
8. Remove the oil filter by rotating counterclockwise with an oil filter wrench.
9. Clean the contact surface of the oil filter adapter; apply light coat of clean oil to new filter's rubber seal.
10. Install the new oil filter.
11. Fill with oil per oil selection chart and capacity (4.7 L / 5.0 qt).
12. Reconnect the battery negative lead last and reconnect battery charger power.
13. Start the generator set and check for leaks around the oil filter; tighten if necessary.
14. Stop the generator set, check oil level, and add oil to bring to the Full mark.
15. Reset the maintenance timer on the RDC2 controller.

⚠ Hot engine oil can cause severe injury or death. Avoid skin contact with hot oil.

⚠ Do not work on the generator set until it cools.

⚠ Accidental starting can cause severe injury or death. Remove the negative (--) lead first when disconnecting the battery.

Tools: Funnel, Drain tube (3/8 in. inside diameter), Catch basin / drain pan

1. Disable set: press OFF button, disconnect battery charger power, remove battery cables, negative (--) lead first.
2. Drain the oil while it is warm. On most models a drain plug is on the service side, opposite the starter.
3. For most models remove one oil drain plug and the oil fill cap/dipstick; aim the drain tube into a catch basin.
4. For most models open the valve near the oil sump and allow ample time for complete drainage.
5. Close the valve and place the tube back in the clip on the bulkhead wall.
6. For 8/10/12RESV(L), cover the alternator with rags near the oil drain valve and oil filter.
7. For 8/10/12RESV(L), place a drain tube (3/8 in. inside diameter) onto the oil drain valve into a drain pan.
8. For 8/10/12RESV(L), open the oil drain valve, remove the dipstick and oil fill cap, and drain completely.
9. For 8/10/12RESV(L), close the oil drain valve and remove the oil drain tube.
10. Remove the old filter, tilting it upward to prevent spilling, and wipe off the adapter/base on the engine.
11. Place a new replacement filter open end up in a shallow pan; pour new oil (provided) through the threaded center hole to the bottom of threads.
12. Allow a minute or two for the oil to be absorbed by the filter material.
13. Apply a thin film of clean oil to the rubber gasket on the new oil filter.
14. Install the new oil filter; hand tighten clockwise until the gasket contacts the adapter, then tighten an additional 3/4--1 turn.
15. Fill the crankcase with new oil to the F/FULL mark on the dipstick; reinstall cap/dipstick, reconnect battery cable negative (--) lead last, test run, check for leaks, and recheck oil level.

⚠ Disconnect the battery cables before working on the generator set. Remove the negative (--) lead first when disconnecting and reconnect it last.

1. Press the OFF button on the generator set controller.
2. Disconnect the utility power to the generator set.
3. Disconnect the generator set engine starting battery, negative (--) lead first.

⚠ Servicing the air cleaner: a sudden backfire can cause severe injury. Do not operate with the air cleaner removed.

Tools: 13/16 in. socket, 5/8 in. spark plug socket, Wire feeler gauge, Torque wrench

1. Disable set: press OFF button, disconnect battery charger power, remove battery cables, negative (--) lead first.
2. Clean or blow out the area around the base of the plug(s) before removal to keep dirt out of the engine; wear eye protection.
3. Using a spark plug socket, remove and discard the old spark plug(s).
4. 24RCL, 30RCL, and 38RCLB: use a 13/16 in. socket. Other models: use a 5/8 in. spark plug socket.
5. Check and set the gap of the new spark plug(s) using a wire feeler gauge.
6. Adjust the gap by carefully bending the ground electrode.
7. Apply a light coating of anti-seize lubricant to the spark plug threads and wipe away any excess compound.
8. Install the new spark plug(s) and torque as shown in Figure 4.
9. Reconnect the spark plug lead(s).
10. Reconnect the battery cable, negative (--) lead last.