Generac 9344 Generator Set

⚠ Do not exceed a no-load speed of 63.5 Hertz.

Tools: AC frequency meter, AC voltmeter

1. Connect an accurate AC frequency meter and voltmeter to the proper generator leads.
2. Start the engine, let it stabilize and warm up at no-load.
3. Read the no-load AC frequency and voltage.
4. If frequency is high or low, turn the governor adjusting screws to obtain a no-load frequency as close as possible to 62 Hertz.
5. Apply an electrical load close to the unit's rated load; if frequency drops below 58 Hertz, set no-load frequency slightly higher than 62 Hertz.
6. Continue until frequency at rated load is 58 Hertz or more.

Tools: Shims

1. Install the injection pump using a shim 0.5mm (0.020 inch) thick.
2. Remove the delivery holder at the front of the injection pump.
3. Remove the delivery valve (IN); reinstall the spring and the delivery holder.
4. Move the governor control lever to its full increase position to deliver fuel with No. 1 piston around 25 degrees BTDC.
5. Slowly turn the crankshaft clockwise until fuel stops coming from the delivery holder; check piston position (16.5-17.5 BTDC).
6. If piston position is later than 16.5 BTDC use a thinner shim; if earlier than 17.5 BTDC use a thicker shim.
7. Assemble the delivery valve (IN); tighten the delivery holder to 29-33 Ft.-Lbs.

⚠ Do not force the potentiometer against its stop.

Tools: AC frequency meter

1. Turn the overspeed shutdown potentiometer counterclockwise until it just contacts its stop.
2. Connect an accurate AC frequency meter across the generator's AC output leads.
3. Start the engine, let it stabilize and warm up.
4. Use the injection pump throttle lever to slowly increase engine speed until the frequency meter reads 69-71 Hertz.
5. Hold the throttle at 69-71 Hertz and slowly turn the overspeed shutdown pot clockwise; when the engine shuts down, setting is correct.

Tools: Feeler gauge, Wrench

1. Loosen the nut, then adjust intake and exhaust valve clearance to 0.008 inch (0.2mm) by turning the adjust screw.
2. Adjust valve clearance with engine cold.
3. Set No. 1 piston at top dead center; adjust intake and exhaust valves of No. 1 cylinder and exhaust valve of No. 2 cylinder.
4. Turn the crankshaft 240 degrees counterclockwise (viewed from the front).
5. Adjust No. 3 cylinder intake and exhaust valves and the intake valve of No. 2 cylinder.

⚠ Do not force the regulator's adjustment potentiometer past its stops or damage can result.

Tools: AC voltmeter

1. Make sure the unit's no-load frequency is correct; readjust the engine governor if necessary.
2. With unit running at no-load, slowly turn the Voltage Adjust potentiometer until voltage is within specified limits.

⚠ Do not force the regulator's adjustment potentiometer past its stops.

Tools: AC voltmeter, AC frequency meter

1. Gain access to the voltage regulator in the generator control panel.
2. If a new regulator is installed, set switch SW1 to Position 2.
3. With unit shut down, turn Voltage Adjust pot fully counterclockwise; set Gain and Stability to mid-position.
4. Do not adjust the Underfrequency Adjust pot.
5. Start the engine and let it stabilize and warm up at no-load; verify frequency 60.5-63.5 Hertz.
6. Turn the Voltage Adjust pot to obtain 242-254 volts line-to-line or 121-127 volts line-to-neutral.
7. If the Regulator lamp flashes, turn the Stability pot until flashing stops.

Tools: Battery capacity tester, Charger

1. With the battery connected to tester, turn the load knob until a current draw equal to three times the battery rating is selected.
2. Hold the current draw for 15 seconds, then observe battery voltage.
3. If voltage remains at 9.6 volts or more, the battery is good.
4. If voltage drops below 9.6, connect the battery to a charger at its fast charge rate (do not exceed 40 amps).
5. After three minutes check the voltmeter; if reading is greater than 16.5 volts, replace the battery.

Tools: Ohmmeter or VOM

1. Remove the connector from the glow plug.
2. Check each glow plug for continuity between the plug terminal and metal.
3. If continuity is indicated, replace the glow plug.

Tools: None

1. Start engine and let it run at no-load with electrical loads turned off.
2. Remove the wire from the switch terminal.
3. Hold the wire terminal end against a clean frame ground.
4. The engine should shut down.

⚠ Meggers and Hi-Pot testers deliver high voltage; do not touch generator or test leads

⚠ Do not apply tester voltages longer than 1 second

Tools: Hi-Pot tester or megohmmeter

1. Disconnect electronic components, regulators, diodes and surge protectors.
2. Isolate all stator leads from ground and connect them together.
3. Connect red test lead to bunched stator leads; black lead to clean frame ground.
4. Set tester voltage switch to 2000 volts; apply voltage for one second only.
5. If Breakdown lamp lights, clean and dry the stator and repeat the test.
6. Replace stator assembly if Breakdown lamp lights on second test.

1. Start the engine and let it run at no load with electrical loads turned off.
2. Remove the wire from the switch terminal.
3. Hold the wire terminal end against a clean frame ground; the engine should shut down.

⚠ Rotor must be completely isolated from the voltage regulator; brush wires No. 1 and 4 must not touch any part of frame during the test.

Tools: Hi-Pot tester or megohmmeter

1. Make sure brushes and brush holders are removed and rotor is isolated from ground and other components.
2. Disconnect excitation leads No. 1 and 4 from the brushes.
3. Connect red test lead to the positive (+) slip ring nearest the rotor bearing.
4. Connect tester black lead to a clean frame ground on the rotor.
5. Set tester Voltage switch to 500 volts; turn tester ON and check Pilot lamp.
6. Set Voltage switch to 1250 volts; wait one second, then turn tester OFF.