Cummins/Onan KTT52 Generator Set

1. Close the main line circuit breaker and apply approximately 1/4 of the rated load.
2. Make sure the engine speed is constant.
3. Turn the GAIN potentiometer clockwise slowly until the engine speed is not constant.
4. Slowly turn the potentiometer counterclockwise until a constant speed is achieved, then an additional 1/2 division.

1. For 60 Hz full load, set engine no-load governed speed to 60.0 Hz (1800 RPM) isochronous, 61.8 Hz (1854 RPM) for 3% droop, or 63.0 Hz (1890 RPM) for 5% droop.
2. For 50 Hz full load, set engine no-load governed speed to 50.0 Hz (1500 RPM) isochronous, 51.5 Hz (1545 RPM) for 3% droop, or 52.5 Hz (1575 RPM) for 5% droop.
3. Use the SPEED ADJUST potentiometer on the engine instrument panel for fine speed adjustments of less than ±100 RPM.

1. Idle Speed potentiometer: turn screw counterclockwise 20 turns then clockwise 10 turns to set mid position.
2. Run Speed potentiometer: turn screw counterclockwise 20 turns then clockwise 10 turns to set mid position.
3. Gain potentiometer: turn the screw fully counterclockwise.
4. Droop potentiometer: turn fully counterclockwise for isochronous operation; approximately 40 for 3 percent droop; approximately 80 for 5 percent droop.

⚠ Do not blow dry with compressed air.

⚠ Filters should be handled with care to prevent damage; if damaged, install recommended replacement part.

Tools: Low pressure compressed air source

1. Loosen fastener(s) and remove air cleaner housing end cap.
2. Remove the air filter element from the filter housing.
3. To clean, blow low pressure compressed air (30 psi/207 kPa) through the element from the clean side; hold nozzle at least 1 inch (25 mm) away.
4. Soak the filter for at least 15 minutes in water and Donaldsons D1400 solvent (or equivalent cleaning solvent).
5. Rinse with clean water (low pressure) and allow to air dry; reinstall when dry. Replace the filter after two cleanings.

⚠ Do not use antifreeze with an anti-leak formula; the stop leak element can prevent or retard coolant flow through the filter.

1. Close the shutoff valves.
2. Unscrew the coolant filters and discard.
3. Apply a light coat of lubricating oil to the gasket surface.
4. Install a new filter and tighten by hand until the seal just touches the filter head, then an additional one-half to three-fourths turn.
5. Open the shutoff valves.

⚠ Contact with hot coolant can result in serious burns. Do not bleed hot, pressurized coolant from a closed cooling system.

⚠ Be sure the electric solenoid valve used with city water cooled sets is open before initial starting of unit.

1. Remove the cooling system pressure cap and fill the system with water or a water/antifreeze mixture.
2. On initial fill, the precharge water filter automatically adds the required anti-corrosion chemicals.
3. When the engine is first started, remove the pressure cap and monitor the coolant level.
4. As trapped air is expelled, add additional coolant.
5. Replace the pressure cap when the coolant level is stable.

⚠ Excessive air pressure while starting the water flow could split the radiator core. Apply air pressure gradually to avoid damage.

Tools: Flushing gun nozzle

1. Use a good cooling system cleaner such as sodium bisulphate or oxalic acid and follow the supplier's instructions.
2. Neutralize and flush with clean water.
3. Open the upper and lower radiator hose connections and install the radiator cap.
4. Attach a flushing gun nozzle to the lower radiator hose connection and let water run until the radiator is full.
5. Gradually apply air pressure to avoid damaging the core; shut off air and allow radiator to refill.
6. Repeat flushing procedure until water coming from the radiator is clean.
7. To flush the engine block, remove the thermostat, attach the flushing gun to the upper radiator hose and fill the block with water.
8. Restrict the lower radiator hose opening until the block is filled, apply air pressure and force water from the lower opening.
9. Repeat until water from the lower radiator hose is clean.
10. Replace the thermostat and all hoses and refill cooling system.

⚠ Crankcase pressure can blow out hot oil and cause serious burns. Do NOT check oil while the generator set is operating.

⚠ Do not operate the engine with the oil level below the low mark or above the high mark.

1. Start the generator set and allow engine to warm up to operating temperature, then shut off.
2. Ensure Automatic Start switch is at OFF position and negative (-) battery cable is disconnected.
3. Remove oil drain plug or open drain valve and collect engine oil in a suitable waste container.
4. When crankcase is drained, replace drain plug or close drain valve and torque to 60-70 ft.-lb (81-95 N·m).
5. Unscrew the oil filters and discard.
6. Apply a light coat of oil to the gasket sealing surface of the new filters and fill filters with clean, new oil.
7. Install filters and tighten 2/3 turn by hand after the seal touches the sealing surface of the bracket. Do not overtighten.
8. Fill the crankcase with the amount of oil to achieve reading at high mark of dipstick.
9. Reconnect the negative (-) starting battery cable, start the engine and check for oil leaks.
10. Shut off the engine, wait 15 minutes, and then check the oil level. Add oil if required.