Cummins/Onan 4KY Generator Set

⚠ Generator voltage is deadly

1. Remove control panel for access to generator leads and circuit breaker terminals.
2. Reconnect generator leads in accordance with appropriate reconnection diagram.
3. Check voltage after reconnections.
4. Adjust no-load voltage with adjustment pot on control panel as necessary.

⚠ Exhaust gas is deadly

⚠ Hot exhaust tailpipe can ignite oil drain spills

⚠ Excessive back pressure can cause engine damage

Tools: U-bolt muffler clamps, tailpipe hangers

1. Use 18-gauge 1-1/8 inch I.D. aluminized steel tubing or equivalent; do not use flexible pipe.
2. Clamp tailpipe to muffler with U-bolt muffler clamp.
3. Support tailpipe longer than 1-1/2 feet near end and at intervals of 3 feet or less.
4. Use automotive-type tailpipe hangers; do not attach to combustible material.
5. Use U-bolt clamps to connect tailpipe sections; slot overlapping pipe maximum 3/4 inch both sides.
6. Do not route tailpipe near fuel lines or fuel tanks.
7. Keep tailpipe at least 3 inches (76 mm) from combustible material unless insulated or shielded.
8. Do not route tailpipe underneath oil drain or restrict air outlet.
9. Do not route tailpipe into approach/departure angles or below axle clearance line.
10. Do not interconnect genset and vehicle engine exhaust systems.
11. Extend tailpipe at least 1 inch (25 mm) beyond vehicle perimeter and 6 inches (153 mm) from openings.
12. Ensure tailpipe deflector does not cause excessive back pressure.

⚠ Genset can fall from vehicle if supporting structure is weak

⚠ Fire is deadly; install fire-resistive barrier

⚠ Exhaust gas and fire are deadly

1. Verify support structure resists dynamic weight: ±561 lbs vertical (±3 g) and ±187 lbs horizontal (±1 g).
2. Secure genset with six 5/16-18 NC bolts; protrude at least 1-1/2 threads beyond weld nuts, maximum 1/2 inch.
3. For below-floor mounting, use Onan mounting kit and Underfloor Template 539-1535; reinforce wood floor with steel.
4. For above-floor mounting, construct vapor-tight, fire-resistive compartment of 26 gauge galvanized steel or equivalent.
5. Shield cooling air openings from rain, road splash and debris.
6. Provide access for fuel and battery connections and periodic maintenance; use Compartment Template 539-1546 for oil drain cutout.
7. Do not share compartment or ventilation with batteries or fuel tanks.
8. Provide at least 40 in2 (258 cm2) free-air inlet; keep cooling air unobstructed.
9. Maintain required clearances: 1 inch left, 1/4 inch sides, 1 inch top, 1-1/2 inch front if inlet not aligned.
10. Use self-extinguishing acoustic insulation rated at least 200°F (90°C); do not line compartment bottom.

⚠ Exhaust gas is deadly; seal all wiring openings

1. Push remote control wire harness connector through entrance hole and snap to genset connector.
2. For harness made by others, use insulated 18 AWG copper conductors up to 30 feet (9 metres).
3. Use heavier gauge conductors for greater distances and flexible sheathing to protect wiring.
4. Route control leads separately from AC power leads.
5. Seal opening where leads enter vehicle interior with silicone rubber or equivalent.

⚠ Excessive fuel pressure can flood genset causing fire

⚠ Sparks can ignite gasoline

Tools: stainless steel hose clamps

1. Contact vehicle chassis manufacturer regarding second fuel pickup installation.
2. Do not change fuel fill tube, fill limiter vent, vapor canister, vapor lines, filler cap or fuel system without approval.
3. Terminate genset pickup above vehicle pickup to prevent running vehicle out of fuel.
4. Use 1/4 inch I.D. fuel hose (SAE 30-R7) and stainless steel hose clamps for connection.
5. Run fuel line at or above top of fuel tank; maximum fuel pump lift 36 inches (914 mm).
6. Route fuel lines away from electrical wiring and hot exhaust components.

⚠ Batteries give off explosive gases

⚠ Exhaust gas is deadly

1. Complete Installation Review checklist.
2. Connect battery cables to battery, positive (+) cable first.
3. Read Operator’s Manual and perform maintenance and pre-start checks.
4. Check engine oil level before starting.
5. Start and operate genset following Operator’s Manual instructions and safety precautions.
6. Check for fuel and exhaust leaks and unusual noises under full and intermediate loads.
7. Do not place genset in service until all fuel and exhaust leaks are fixed and operation is satisfactory.