Cummins/Onan KTT52 Generator Set

1. Idle Speed potentiometer: turn the screw counterclockwise 20 turns, then clockwise 10 turns to set mid position.
2. Run Speed potentiometer: turn the 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.
5. Droop potentiometer: turn to approximately 40 for 3 percent droop, or approximately 80 for 5 percent droop.

1. After the gain adjustment is made, adjust full load governed engine speed to equal the desired speed (60 Hz, 1800 RPM or 50 Hz, 1500 RPM).
2. Use the SPEED ADJUST potentiometer on the engine instrument panel for fine speed adjustments of less than +/-100 RPM.

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

⚠ Filters should be handled with care to prevent damage. If the filter does become 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 the nozzle at least 1 inch (25 mm) away to avoid damaging the element.
4. Soak the filter for at least 15 minutes in water and Donaldsons D1400 solvent (or equivalent other cleaning solvent) to remove soot and carbon as well as dirt.
5. Rinse with clean water (low pressure) and allow to air dry. Do not blow dry with compressed air. Reinstall when the filter element is dry.
6. Replace the filter after two cleanings to avoid restricting the airflow.

⚠ Do not use antifreeze with an anti-leak formula. The stop leak element can prevent or retard the 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. Tighten an additional one-half to three-fourths turn.
5. Open the shutoff valves.

⚠ Be sure the electric solenoid valve used with city water cooled sets is open before initial starting of unit, otherwise overheating and damage to the engine can result.

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

1. Remove the cooling system pressure cap and fill the system with water or a water/antifreeze mixture.
2. On the initial fill, the precharge water filter will automatically add 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, the coolant level will drop and additional coolant should be added.
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. Open the upper and lower radiator hose connections and install the radiator cap.
2. Attach a flushing gun nozzle to the lower radiator hose connection and let the water run until the radiator is full.
3. When full, gradually apply air pressure to avoid damaging the core.
4. Shut off the air and allow the radiator to refill.
5. Repeat flushing procedure until the water coming from the radiator is clean.
6. To flush the engine block, first remove the thermostat to allow the water to fill the block.
7. Attach the flushing gun to the upper radiator hose and fill the block with water. Restrict the lower radiator hose opening until the block is filled.
8. Apply air pressure and force water from the lower opening. Repeat until the water coming from lower radiator hose is clean.
9. 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.

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