Service parts for the T04073
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
| Fuel | Gasoline/LPG/NG |
|---|---|
| Frequency | 60.0 Hz |
| Oil capacity | 0.6 L |
| Voltage options | 120/240 V |
| Phase | Single |
| Power factor | 1 |
| Fuel tank | 19.0 L |
Maintenance & consumables
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Air Cleaner Bracket | 336713526 | eBay | ||
| Battery | 12V sealed lead acid 7.5AH, 151x65x97mm | — | |||
| Oil | FIRMAN SAE 10W-30 API SL | 0.6 L | — | 100 hr | |
| Spark plug | electrode gap 0.020-0.024 in. (0.5-0.6mm) | 330723001 | eBay $9.99 |
Service intervals
11| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Engine Oil | Check | 25 hr | First service — check oil level, initial 25 hours | |
| Fittings/Fasteners | Check | 50 hr | First service — initial 25 hours | |
| Air Filter | Clean | 50 hr | clean, replace if necessary | |
| Fuel Line | Check | 50 hr | check for leakage, retighten or replace gasket if necessary | |
| Spark Plug | Check | 50 hr | check condition, adjust gap and clean | |
| Engine (fuel hose) | Check | 100 hr | 12 mo | check fuel hose for cracks or other damage, replace if necessary |
| Engine Oil | Change | 100 hr | change every 100 hours; for new engine change after 25 hours | |
| Exhaust System | Check | 100 hr | 12 mo | check adjust valve clearance, clean combustion chamber |
| Spark Plug | Replace | 100 hr | 12 mo | |
| Fuel Tank Strainer | Clean | 250 hr | clean fuel tank strainer, replace if necessary | |
| Spark Arrester Screen | Clean | 250 hr | clean/replace if necessary |
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
4| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Clearance | Exhaust Valve Clearance | 0.004-0.006 | in. (0.10-0.15 mm) | |
| Clearance | Intake Valve Clearance | 0.004-0.006 | in. (0.10-0.15 mm) | |
| Gap | Spark Plug Electrode Gap | 0.020-0.024 | in. | |
| Pressure | Natural gas fuel pressure range | 7-11 inches water column (0.25-0.40 psi)(13-20mm mercury)(1.7-2.7 kpa) |
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 |
|---|---|---|---|---|---|
| Engine oil | SAE 10W-30 API SL | API SL or higher | 0.6 L | Other high-quality detergent oils API SL or higher acceptable; full synthetic 5W-30, 5W-30, 10W-40, 10W-30 by temperature chart | |
| Fuel | Unleaded gasoline min 87 octane, max 10% ethanol | 19.0 L | 5.0 US Gallons; at altitudes over 5000ft, min 85 octane acceptable |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Procedures
7Add Engine Oil maintenance
⚠ Do not attempt to crank or start engine before properly filled with oil
Tools: oil funnel
- Place generator on flat, level surface
- Clean area around oil fill and remove oil fill cap/dipstick
- Wipe dipstick clean
- Using oil funnel, slowly pour oil into fill opening until it reaches upper limit H mark on dipstick
- Replace oil fill cap/dipstick and fully tighten
- Check oil level prior to each use or at least every 8 hours of operation
Air Filter Maintenance maintenance
- Carefully remove foam air filter element and wash with liquid detergent and water only, squeeze dry in clean cloth
- Saturate foam air filter element with clean engine oil and squeeze in clean cloth to remove excess oil
- Reinstall clean or new air filter element
Change Engine Oil maintenance
⚠ Avoid prolonged or repeated skin contact with used motor oil
- On level surface drain oil into suitable container by removing drain plug and oil filler cap while engine is warm
- Reinstall drain plug and fill engine with oil until it reaches HIGH(H) level on dipstick
Inspect Muffler and Spark Arrester maintenance
Tools: wire brush
- Inspect muffler for cracks, corrosion, or other damage
- Remove screws securing spark arrester and remove from muffler
- Carefully remove carbon deposits from spark arrester screen with wire brush
- Replace spark arrester if damaged, using only FIRMAN OEM parts
- Position spark arrester in muffler and attach with screws
Long Term Storage maintenance
⚠ Fuel and vapors are extremely flammable
- Treat any stored fuel with fuel stabilizer
- When storing with gasoline in tank, operate engine 5-10 minutes to circulate treated fuel
- No need to drain gasoline if fuel stabilizer added
- If draining fuel tank, run generator outdoors until it stops from lack of gasoline
- Always turn main fuel selector switch to OFF prior to storage
- Allow generator to cool before cleaning and storage
- Change oil
- Remove spark plug boot and spark plug, pour about one teaspoon of engine oil through spark plug hole, pull recoil starter several times
- Cover generator and store in clean, dry place out of direct sunlight
Spark Plug Maintenance maintenance
Tools: spark plug wrench
- Remove spark plug boot
- Remove spark plug using provided wrench
- Inspect spark plug for damage and clean with wire brush before reinstalling, replace if damaged
- Adjust electrode gap to 0.020-0.024 in. (0.5-0.6mm)
- Seat spark plug in position and thread by hand to prevent cross threading
- Tighten plug with provided wrench and put spark plug boot back on
Battery Replacement repair
- Remove spark plug boot from spark plug
- Remove nut and bolt from negative post first, then positive post
- Loosen and remove cap screws and nuts on battery holding bracket
- Remove battery and recycle
- Install new battery: 12V sealed lead acid 7.5AH, 151x65x97mm
- Connect red positive battery cable to battery first
- Connect black negative battery cable to battery second
- Cover posts with boots provided
- Install spark plug boot onto spark plug
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
What fuel type does the Firman T04073 take?
The Firman T04073 runs on Gasoline/LPG/NG.
What air filter fits the Firman T04073?
The Firman T04073 uses air filter part number 336713526.
Troubleshooting
7Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Engine is running, but no AC output is available. | 1. Circuit breaker is open. 2. Fault in generator. 3. Poor connection or defective cord set. 4. Connected device is bad. | 1. Reset circuit breaker. 2. Contact authorized service facility. 3. Check and repair. 4. Connect another device that is in good condition. |
| Engine runs good at no-load but “bogs down” when loads are connected. | 1. Short circuit in a connected load. 2. Engine speed is too slow. 3. Shorted generator circuit. | 1. Disconnect shorted electrical load. 2. Contact authorized service facility. 3. Contact authorized service facility. |
| Engine will not start; starts and runs rough or shuts down when running. | 1. Fuel selector switch set to OFF (O) position. 2. Low oil level. 3. Dirty air cleaner. 4. Out of gasoline. 5. Stale gasoline. 6. Spark plug wire not connected to spark plug. 7. Bad spark plug. 8. Water in gasoline. 9. Flooded. 10. Excessively rich fuel mixture. | 1. Set fuel selector switch to “GAS” or “LPG/NG” position. 2. Fill crankcase to proper level or place generator on level surface. 3. Clean or replace air cleaner. 4. Fill fuel tank with gasoline. 5. Drain fuel tank and carburetor; fill with fresh gasoline. 6. Connect wire to spark plug. 7. Replace spark plug. 8. Drain gas tank and carburetor; fill with fresh gasoline. 9. Wait 5 minutes and re-crank engine. 10. Contact authorized service facility. |
| Engine lacks power. | 1. Load is too high. 2. Dirty air filter. | 1. Don't Overload Generator 2. Replace air filter. |
| Engine“hunts”or falters. | 1. Carburetor is running too rich or too lean. 2. Clogged or dirty fuel filter. 3. Clogged or dirty fuel filter. 4. Clogged spark arrester. | 1. Contact authorized service facility. 2. Clean or replace fuel filter. 3. Clean or replace fuel filter. 4. Clean or replace spark arrester. |
| Engine shuts down when running. | 1. Out of gasoline or LPG/NG. 2. Dirty air cleaner. 3. Low oil level. 4. Clogged or dirty fuel filter. | 1. Fill fuel tank with gasoline or replace LPG cylinder / check NG supply. 2. Clean or replace air cleaner. 3. Fill crankcase to proper level or place generator on level surface. 4. Contact authorized service facility. |
| Engine shuts down and yellow CO fault light blinking. | 1. CO system fault | 1. Contact authorized FIRMAN service facility. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Parts
20| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 330723001 | Spark Plug | 1 | Spark plug | eBay $9.99 |
| 336713526 | Air Cleaner Bracket | 1 | Air filter | eBay |
| 336723551 | Gasket, Carburetor | 1 | Gasket | eBay $15.99 |
| 336723552 | Gasket, Air Cleaner | 2 | Gasket | eBay |
| 336723567 | Air Cleaner Set | 1 | Air filter | eBay |
| 336723569 | Element, Air Cleaner | 1 | Air filter | eBay |
| 336723614 | Starter Motor Assembly | 1 | Starter | eBay $49.99 |
| 336728301 | Recoil Starter Knob | 1 | Starter | eBay |
| 340713007 | Seal, Oil | 2 | Seal | eBay |
| 340713011 | Gasket, Cylinder Head | 1 | Gasket | eBay |
| 340715501 | Muffler Gasket | 2 | Gasket | eBay |
| 340715510 | Starter Assy | 1 | Starter | eBay |
| 336713529 | Holder, Spark Arrester | 1 | Service part / kit | eBay |
| 336713533 | Muffler Assembly | 1 | Service part / kit | eBay |
| 336713590 | Charger | 1 | Service part / kit | eBay |
| 336713820 | Battery | 1 | Service part / kit | eBay |
| 336723609 | Ignition Coil | 1 | Service part / kit | eBay |
| 340415504 | Carburetor | 1 | Service part / kit | eBay |
| 340715500 | Arrester, Spark | 1 | Service part / kit | eBay |
| 340715505 | Control Module&vf Module | 1 | Service part / kit | eBay |
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 |
|---|---|---|---|
| Standby | 1.7 | 0.45 |