Service parts for the 4456
Grouped by system, with how many of each the parts manual calls for.
Air intake
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Standby power | 10 kW |
|---|
Maintenance & consumables
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Air Filter (GH410/GT760/GT990) | 0C8127 | Amazon eBay $15.99 NAPA $24.03 FridayParts $21.87 | ||
| Oil filter | Oil Filter (liquid cooled) | 070185 | Amazon eBay $30.00 NAPA $3.59 FridayParts $45.99 |
Service intervals
1| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Battery | Inspect | 1 mo | Monthly battery inspection; reset the exercise timer after performing it. |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Service specifications
18| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Clearance | Drive belt tension - compressed length of tensioning springs | 5/8 | inch (16mm) | by turning the two adjusting bolts |
| Gap | Starter pinion to ring gear backlash | .020-.035 | inch | measure at eight equally spaced locations with manual engagement |
| Other | Fuel regulator adjuster dimension (top of adjuster screw to top of threaded casting) | 5mm | mm | after removing freeze plug |
| Pressure | Fuel supply pressure to generator regulator | 11 | inches of water column | |
| Pressure | LOS switch (P/N 99236) test air pressure | 20 | PSI | apply 20 PSI air pressure to switch |
| Pressure | LP fuel pressure to generator fuel inlet | 11 to 14 | inches of water column (0.6 psi) | |
| Pressure | Natural gas fuel supply pressure to generator fuel inlet | 11 to 14 | inches of water column | at generator fuel inlet |
| Pressure | Oil pressure | 10-30 | psi | engine running |
| Resistance | 057522 Low Coolant Level sensor resistance | 45 to 60 | ohms | with wire 85 disconnected, from sensor connector to body (ground) |
| Valve clearance | Valve lash | .002-.004 | ||
| Voltage | Battery charger / utility sensing voltage (red wire pcb pin #14 to #225A pcb pin #15) | 14-16 | vac | |
| Voltage | Battery voltage during cranking | 11 | volts DC | minimum; below this recharge/replace battery |
| Voltage | Line to line voltage (#T1 pcb pin #17 to #T2 pcb pin #16) | 208 or 240 | vac | must be line to line value |
| Voltage | PCB #14 wire (J1-7) to ground (J1-13) | greater than 10 | volts DC | while engine is cranking |
| Voltage | PCB #23 wire (J1-3) and #194 wire (J1-4) | greater than 10 | volts DC | in Auto |
| Voltage | PCB #56 wire (J1-5) to #0 wire (J1-13) | greater than 10 | volts DC | within 5 seconds of placing unit to manual |
| Voltage | PCB J1-14 (red wire) to J1-15 (#225A wire) | greater than 12 | V AC | in Auto; from secondary winding of utility sensing transformer |
| Voltage | Starter contactor terminal voltage during cranking | 11-12 | volts DC | during cranking |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Recommended fluids
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Coolant | low silicate antifreeze | Cooling system should be completely drained and flushed. Only de-ionized water and low silicate anti-freeze and additives should be used. If not available use pre-mixed 50/50 low silicate antifreeze and low silicate supplemental additives. Do not over-concentrate; never exceed a 60/40 mixture. Anti-freeze should never be added to an engine without being mixed with water first. |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Fault codes
32| Code | Name | Meaning | Severity | Action |
|---|---|---|---|---|
| 00 | Open | Reason For Failure | ||
| 01 | Shorted | Reason For Failure | ||
| 02 | Missing / Wrong | Reason For Failure | ||
| 03 | Frozen / Tight / Rough | Reason For Failure | ||
| 04 | Broken / Cracked | Reason For Failure | ||
| 05 | Burnt / Bent / Distorted | Reason For Failure | ||
| 06 | Leak | Reason For Failure | ||
| 07 | Miswired / Misadjusted | Reason For Failure | ||
| 08 | Defective | Reason For Failure | ||
| 09 | Post Manuf. Update | Reason For Failure | ||
| 10 | Dirty / Clogged | Reason For Failure | ||
| 11 | Loose | Reason For Failure | ||
| 12 | Weak | Reason For Failure | ||
| 13 | Noisy | Reason For Failure | ||
| 14 | Re-establish Magnetism | Reason For Failure | ||
| 15 | Rebuilt Stock | Reason For Failure | ||
| 16 | New Defective | Reason For Failure | ||
| 17 | PCB Timer Wiring | Reason For Failure | ||
| 99 | Other / Misc | Reason For Failure | ||
| A | Alternator | Primary Failure Code (What System?) | ||
| C | PCB - Control Circuitry | Primary Failure Code (What System?) | ||
| D | Fuel Systems | Primary Failure Code (What System?) | ||
| E | Engine Related | Primary Failure Code (What System?) | ||
| F | Control Panel | Primary Failure Code (What System?) | ||
| G | Governor | Primary Failure Code (What System?) | ||
| H | Ignition System | Primary Failure Code (What System?) | ||
| L | Transfer Switch | Primary Failure Code (What System?) | ||
| O | Oil System | Primary Failure Code (What System?) | ||
| P | Gear Box | Primary Failure Code (What System?) | ||
| S | Sheet Metal | Primary Failure Code (What System?) | ||
| W | Water System | Primary Failure Code (What System?) | ||
| Z | Other (Misc) | Primary Failure Code (What System?) |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
12Drive Belt Tension adjustment
⚠ On all new product make sure the belt tension is inspected before it is installed.
- Remove all covers and inspect belt for proper tensioning.
- Turn the two adjusting bolts until the compressed length of the springs is 5/8 inch (16mm).
Fuel Regulator Adjustment (hard starting GV410 gaseous fueled product) adjustment
⚠ Under no circumstances should this adjuster be completely removed.
⚠ A new freeze plug part # D2529 MUST be reinstalled to retain the tamperproof status of the regulator.
Tools: Spark tester, Feeler gauge
- Check for proper spark using a spark tester.
- Check for proper fuel supply to the regulator; 11 inches of water column should be available.
- Check valve lash; valves should be set between .002-.004.
- Verify the regulator is not stuck (manually choke the unit to start, then retry).
- Remove the freeze plug located directly above the inlet.
- Unscrew the threaded adjuster to achieve 5mm from the top of the adjuster screw to the top of the threaded casting.
- Start the generator a number of times until satisfied the condition is fixed.
- Reinstall a new freeze plug part # D2529 and mark an X across the freeze plug with a permanent marker.
Block Heater Test diagnostic
⚠ In multiple hairpin configurations, one hairpin can fail while the others remain functioning. Note the jumper position so they can be properly reassembled.
Tools: Phillips screwdriver (slip-joint pliers for explosion proof), Needle nose pliers or nut driver, Ohmmeter
- Disconnect the heater from the power source.
- For heaters with a thermostat, allow the coolant to cool below the thermostat range or remove the heater from the engine.
- Check for continuity with an ohmmeter between the element terminals inside the electrical box (remove all wires to avoid a false reading).
- If there is continuity through the element, check for continuity across the thermostat terminals (if applicable).
- If there is no continuity between the element or thermostat terminals the heater has failed; determine the cause of failure.
- If there is continuity through both the element and the thermostat, the heater is fine and the problem is improper installation, faulty wiring or an air pocket.
Check Oil Pressure diagnostic
Tools: Pressure gauge
- Remove plug or LOS switch from engine and install a pressure gauge.
- Start and run engine and note how much oil pressure you have.
GV410 Starter Pinion Jam Procedure diagnostic
⚠ New rubber bumper gets placed at base of block right above sump cover, and on the centerline of the starter.
Tools: Feeler gauge
- Measure the voltage at the starter contactor terminal; verify 11-12 volts DC during cranking.
- If below 11 volts DC, measure at the battery terminals during cranking; recharge/replace battery if below 11 volts DC.
- If battery voltage is above 11 volts DC, check for proper battery cable sizing.
- Manually engage the starter pinion into the ring gear and check for .020-.035 inch backlash, measuring at eight equally spaced locations.
- Shim or remove shims as necessary using shim kit part number 0D4791.
- Visually check that the starter motor is perpendicular to the ring gear; replace the starter motor if the mounting bracket is bent.
- Check position of rectangular rubber bumper part number 0C3794; older units used rubber dimples and should be replaced.
Procedure for Checking Control Board Number 76009A diagnostic
⚠ Record your measurements and include these findings on the Warranty Repair Report or the claim will be rejected.
⚠ Be careful when pushing the SW1 switch, there is LIVE voltage present on the PCB.
- With Auto/Off/Manual in Auto or Manual, check for battery voltage from wire #15A (J1-10) to wire #0 (J1-13); should be 12-14 VDC.
- IF STARTER DOES NOT CRANK: measure #56 wire (J1-5) to #0 (J1-13) within 5 seconds of placing unit to manual; should be greater than 10 VDC.
- If less than 10 VDC, remove #56 wire from J1 housing and re-measure across J1-5 to J1-13; if still less than 10 VDC, replace the board.
- Also check for a short to ground on wire #56 which could damage the board.
- IF STARTER CRANKS BUT UNIT DOES NOT COME UP TO SPEED: measure #14 wire (J1-7) to ground (J1-13) while cranking; should be greater than 10 VDC.
- If less than 10 VDC, remove #14 wire and re-measure J1-7 to J1-13; if still less than 10 VDC, replace the board.
- IN AUTO - UNIT DOES NOT TRANSFER AFTER UTILITY LOSS & 20 SECOND WARM-UP DELAY: measure #23 (J1-3) and #194 (J1-4); should be greater than 10 VDC.
- If not, remove #23 and #194 wires and re-measure J1-3 to J1-4; if less than 10 VDC, replace the board; also check for a short to ground on #194.
- IN AUTO - UNIT DOES NOT TRANSFER BACK TO UTILITY WHEN UTILITY VOLTAGE IS RESTORED: check voltage between J1-14 (red wire) and J1-15 (#225A wire); should be greater than 12 VAC.
- If utility is near rated (208 VAC or 240 VAC) and secondary is less than 12 VAC, check transformer wiring; if greater than 12 VAC and still no return, replace the board.
Test Method for Generac LOS - P/N 99236 diagnostic
Tools: Audible continuity meter, Air pressure source
- Apply 20 PSI air pressure to switch.
- Connect an audible continuity meter to the switch and ground.
- Release the air pressure and note the pressure when the meter sounds.
- Accept the part if the switch closes at the specified pressure; reject if it does not.
Testing the Battery Charger diagnostic
⚠ If the battery voltage measures greater than 13 volts it should be discharged to less than 12.6 volts.
Tools: Current meter, Voltmeter
- Set the exercise timer per the Owner's Manual (this sets the PCB to the zero reading).
- Remove the DC fuse from the control panel.
- Measure the DC voltage at the battery (+)(-) and record; if greater than 13 volts discharge it to less than 12.6 volts.
- Measure current across the fuse holder with the fuse removed (current flow should be into the battery, typically in the .5 amp range).
- If current cannot be measured, reinstall the fuse and measure battery voltage; over ten to fifteen minutes a slow increase should be seen.
Testing the Weekly Exercise Circuit diagnostic
⚠ Be careful when pushing the SW1 switch, there is LIVE voltage present on the PCB.
Tools: Non-conductive device (e.g., pencil eraser), Flashlight
- Remove the DC fuse from the control panel.
- Open the control panel front (be careful not to short any wiring).
- Remove the cover from the CMA box.
- Locate SW1 on the circuit board (76009-A) in the upper right corner.
- Install the fuse back in the control panel.
- Put the Auto-Off-Manual switch in the Auto position.
- Push and hold SW1 with a non-conductive device until the unit starts (about 30 seconds); the unit will run about 20 minutes then shutdown.
Setting the Exercise Timer operation
⚠ The exerciser will only work in the AUTO mode.
⚠ The exerciser will need to be reset every time the 12-volt battery is disconnected and then reconnected.
⚠ The exerciser WILL NOT work if dip switch 2 (Remote Not Auto) is ON.
- Verify that the Auto/Off/Manual switch is set to AUTO.
- Hold down the set timer switch until the generator starts (approximately 10 seconds) and then release.
- The generator will start and run approximately seven (7) or twelve (12) minutes then shut down on its own; the exerciser is set to run at that time weekly.
LP Conversion - Air-cooled standby using 992cc V-Twin engine repair
⚠ The primary regulator for the propane supply is NOT INCLUDED with the generator.
Tools: Pipe thread sealant
- Turn off the main gas supply.
- Remove the three carburetor fuel hoses from the outlet ports of the demand regulator.
- Disconnect wire #0 and wire #14 from the gas solenoid on top of the demand regulator.
- Remove the demand regulator from the enclosure by rotating counterclockwise.
- Remove the small brass hose fitting from the idle circuit port of the regulator housing.
- Remove the small jet (0D5698A) located in the side of the regulator port on the regulator.
- Refit the brass hose fitting to the idle circuit port using pipe thread sealant.
- Identify both adjustment screws (one accessed from the front, one from the back).
- Reverse procedure steps 1-4 to reinstall the demand regulator.
- To run on LP fuel, turn both adjuster screws 1/4 turn clockwise.
- Make minor adjustments to the preset screw settings to achieve maximum power.
Re-positioning fuel hose between fuel solenoid and fuel regulator on the 1.5 liquid cooled Mitsubishi engine repair
⚠ Make sure you have clearance here (new mounting location).
- Remove M8 bolt from clamp located on the side of engine block.
- Reposition fuel hose and clamp to new mounting location on the timing belt case cover.
- Replace M8 bolt and tighten.
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Common questions
How many kW is the Generac 4456?
The Generac 4456 is rated 10 kW standby.
What oil filter does the Generac 4456 use?
The Generac 4456 uses oil filter part number 070185.
What air filter fits the Generac 4456?
The Generac 4456 uses air filter part number 0C8127.
Troubleshooting
7Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| The generator cranks over for an excessive amount of time before starting, or does not start at all. | Check for proper spark using a spark tester. Check for the proper fuel supply to the regulator, 11 inches of water column should be available to the generators regulator. Also check the valve lash for proper adjustment, valves should be set between .002-.004. A sticking regulator can also cause a no start, verify that the regulator is not stuck (manually choke the unit to start, then retry) If all this checks out an adjustment of the regulator can be made. The regulator is fitted with a freeze plug located directly above the inlet. This freeze plug must be removed. Under the plug is a threaded adjuster, which applies a spring pressure to the inlet seal. Unscrew the adjuster to achieve a dimension of 5mm from the top of the adjuster screw to the top of the threaded casting. Under no circumstances should this adjuster be completely removed. Start the generator a number of times until you are satisfied that the condition is fixed. A new freeze plug part # D2529 MUST be reinstalled in to the regulator to retain the tamperproof status of the regulator. As an identification that the regulator has been adjusted put an X across the freeze plug with a permanent marker. | |
| Starter pinion jammed into flywheel on initial cranking. | Measure the voltage at the terminal of the starter contactor and verify 11-12 volts DC is available to the generator during cranking. If voltage is below 11 volts DC, measure at the battery terminals during cranking. If battery voltage is below 11 volts DC, recharge/replace battery. If battery voltage is above 11 volts DC, check for proper battery cable sizing, see owners manual. Manually engage the starter pinion into to ring gear on the flywheel and check for .020-.035 inch backlash. When checking backlash, measure at eight equally spaced locations and make sure the gear teeth are in contact in the direction of rotation. Shim or remove shims as necessary, use shim kit part number 0D4791. Visually check that the starter motor is perpendicular to the ring gear. Replace the starter motor if the starter motor mounting bracket is bent. Check for proper position of rectangular rubber bumper part number 0C3794. Older units used rubber dimples, they should be replaced if jamming is occurring. New rubber bumper gets placed at base of block right above sump cover, and on the centerline of the starter. | |
| The exercise function on some units may be accelerated by approximately 5 minutes per week. | It is recommended that the customer reset the exercise timer after performing the monthly battery inspection, as outlined in the maintenance schedule. | |
| The heater has been subjected to an air pocket preventing the coolant from circulating. | Although the heated coolant can’t circulate, the heater thermostat continues to turn the heater on and off. The engine will then cool down, activating the low coolant temperature alarm. | The engine should be thoroughly ‘purged’ to eliminate any air pockets before the heater is energized. We recommend running the engine up to operating temperature to open the engine thermostat after the installation. This will insure that no air pockets are left within the cooling system. Also check the outlet hose and make sure there is no point in the line where it flows down. Remember that heat rises and a downward trend will stop the flow of hot water. |
| The heater (Fig. 5,6 ) was actually mounted with the outlet facing sideways. | In the pictures it can be seen that the coolant never reached the top portion of the tank. This exposes the hairpins to air and eliminates the heaters ability to ‘pull’ cold coolant from the engine. | It is critical that the heater is completely full of coolant at all times. This means the outlet of the heater must be at the highest point of the heating system for it to work correctly. |
| Over-concentration of coolant will cause a gel-like slime to accumulate on the element. | In severe cases, it may burn on the element causing a black sludge to form. Over-concentration of additives will cause a similar slime, but usually in a different color. | |
| Insufficient Natural Gas fuel pressure supplied to the generator. | Eleven to fourteen inches of water column pressure must be supplied to the generator. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Repair guides
8- Block Heater Test
- Fuel Regulator Adjustment (hard starting GV410 gaseous fueled product)
- GV410 Starter Pinion Jam Procedure
- LP Conversion - Air-cooled standby using 992cc V-Twin engine
- Procedure for Checking Control Board Number 76009A
- Re-positioning fuel hose between fuel solenoid and fuel regulator on the 1.5 liquid cooled Mitsubishi engine
- Testing the Battery Charger
- Testing the Weekly Exercise Circuit
Step-by-step procedures compiled from the Generac service manual for this model.
Parts
8| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 070185 | FILTER, OIL | 1 | Oil filter | Amazon eBay $30.00 NAPA $3.59 FridayParts $45.99 |
| 075281 | SWITCH, HIGH TEMPERATURE | 1 | Sensor | Amazon eBay $39.00 |
| 0C3025 | SWITCH, OIL PRESS | 1 | Sensor | Amazon eBay $16.00 FridayParts $16.50 |
| 0C3040 | PRE-CLEANER | 1 | Air filter | eBay $12.00 |
| 0C8127 | ELEMENT AIR CLEANER | 1 | Air filter | Amazon eBay $15.99 NAPA $24.03 FridayParts $21.87 |
| 0D4529 | SPARKPLUG | 2 | Spark plug | Amazon eBay |
| SE501951 | WATER PUMP (REMAN FOR RE504911) (4412, 4456) | Water pump | Amazon eBay | |
| 0C7720 | Airbox Mixer (GT760/GT990) | Service part / kit | buy |
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.
Fuel consumption
| Rating | Load | L/h | gal/h |
|---|---|---|---|
| Prime | 50% | 105.0 | 27.74 |
| Standby | 50% | 74.0 | 19.55 |
Available documents
This page was generated from the 3 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.