HomeEnginesHonda GX270T2

Honda GX270T2 Engine

The Honda GX270T2 is an engine rated at 3600 rpm. It powers generator sets from Honda, including the EM4000SX. It holds 1.1 L (0.3 gal) of oil.

Also known as: Honda GX270T2

3600 rpm
Rated speed
1.1 L
Oil capacity

Engine specifications

Oil capacity1.1 L
Rated speed3600 rpm

Common problems

8
  • Engine speed does not stabilize
    Fix: Disassemble and inspect for restricted parts. Replace or repair the main wire harness. Check for continuity between the ECM 8P connector wire harness side and junction box 8P connector wire harness side: No continuity, Normal, Abnormal, Normal.
  • Engine hard to start
    Fix: Disassemble the carburetor to check for clogged ports, jets, and nozzles (page 5-10). Restart the engine. Check the control gear box (page 5-7). Remove the carburetor spacer (page 5-4) and check whether the choke valve is closed when pulling the recoil starter.
  • Engine does not stop when engine oil level is low
    Fix: Check the combination switch (page 7-7). Replace the combination switch. Check for open circuit in junction box circuit (page 7-11). Check for open circuit in the yellow wire between the oil level switch and ignition coil.
  • Engine does not stop when combination switch is turned off
    Fix: Check the combination switch (page 7-7). Replace the combination switch. Check for continuity between the ignition coil 4P connector wire harness side and combination switch 2P connector wire harness side: Continuity, No continuity.
  • Engine does not start or is hard to start.
    Cause: Engine lacks power. Engine will not rev sufficiently. ENGINE OIL level low. FUEL STRAINER clogged. IGNITION COIL faulty. CHARGE / POWER COIL faulty. CONTROL GEAR BOX faulty. COMBINATION SWITCH faulty. ECM faulty. SPARK ARRESTER clogged. VALVE or VALVE SEAT worn or damaged. CYLINDER, PISTON, or PISTON RING worn. WIRE HARNESS faulty. OIL LEVEL SWITCH faulty. SPARK PLUG faulty. AIR CLEANER ELEMENT clogged. CARBURETOR faulty. VALVE CLEARANCE incorrect.
  • Does not crank
    Fix: Perform STARTING SYSTEM TROUBLESHOOTING
  • Compression is too low
    Cause: Valve spring free length, Valve seat width, Valve face irregularly worn, Decompressor operation, Piston ring side clearance, Piston ring width, Piston ring end gap, Piston skirt O.D., Cylinder sleeve I.D.
    Fix: Check the valve clearance (page 3-9), and then perform the cylinder compression test (page 11-5). If the cylinder compression is too low, perform a leak-down test.
  • Compression is too high
    Fix: Perform the cylinder compression test (page 11-5). If the cylinder compression is too high, remove carbon deposits in the combustion chamber (page 3-10).

Compiled from service & troubleshooting documentation across every generator set that uses the Honda GX270T2.

Maintenance schedule

ItemSpecCapacityPart #Interval
Air filter
Fuel filter
OilSAE 10W-30 API service classification SJ or later1.1 L
Spark plugBPR5ES (NGK), W16EPR-U (DENSO)

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Service intervals

6
ItemActionHoursMonthsNotes
Engine oilChange20 hr1 moFirst service — First month or 20 hrs
Combustion chamberClean1000 hrAfter every 1,000 hrs
CanisterCheck24 moEvery 2 years
Charge tubeCheck24 moEvery 2 years
Fuel tubeCheck24 moEvery 2 years (Replace if necessary)
Purge tubeCheck24 moEvery 2 years

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

42
TypeItemValueUnitCondition
ClearanceFloat height13.2mm
GapIgnition coil air gap0.2 – 0.6mm
GapSpark plug gap0.70 – 0.80mm
OtherCrank duration3-3-4-5secper automatic attempt sequence
OtherEnclosure dimensions85x58x33mm
OtherLength of cable2m
OtherMax. Standby Current9.8mA @ 12 V
OtherNumber of attempts4automatic starting attempts
OtherPause between each automatic attempt10sec
PressureCylinder compression1.29MPaat 1,400 min-1 (rpm)
PressureCylinder compression1.31MPaat 1,400 min-1 (rpm)
ResistanceCT sensor resistance18 ±2Ω
ResistanceSpark plug cap resistance7.5 – 12.5
SpeedAuto Throttle idle speed2,300 ± 100min-1 (rpm)
SpeedMaximum engine speed3,600 ± 100min-1 (rpm)
TemperatureOperating Temperature Range-30 to +70°C
TorqueAir cleaner case bolt5.4N·m
TorqueCarburetor mount nut8.5N·m
TorqueConnecting rod special bolt14N·m
TorqueControl panel mount bolt27N·m
TorqueCrankcase cover bolt24N·m
TorqueCylinder head bolt35N·m
TorqueEngine mount nut34N·m
TorqueExhaust pipe nut24N·m
TorqueFan cover stud bolt23N·m
TorqueFan cover stud bolt mounting nut40N·m
TorqueFlywheel special nut128N·m
TorqueFlywheel special nut170N·m
TorqueFront housing bolt24N·m
TorqueFuel meter screw4N·m
TorqueFuel valve nut23N·m
TorqueGenerator cooling fan screw4.8N·m
TorqueOil drain bolt22.5N·m
TorqueRear housing cover bolt9.8N·m
TorqueRocker arm pivot adjusting nut10N·m
TorqueRocker arm pivot special bolt24N·m
TorqueRotor bolt44N·m
TorqueRubber mount nut24N·m
TorqueSpark plug18N·m
Valve clearanceValve clearance EX0.20 ± 0.02mm
Valve clearanceValve clearance IN0.15 ± 0.02mm
VoltageDC supply12VDCgenerator battery

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

FluidGradeStandardAmbientCapacityNotes
Engine oilSAE 10W-30API service classification SJ or later1.1 LRecommended oil
FuelRegular unleaded gasolinepump octane rating 86 or higher
GreaseMarine greasewater resistant urea based grease
GreaseMulti-purpose greaseNLGI #2 or equivalentLithium based multi-purpose grease
OtherAutomatic transmission fluidATF

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

9
Setting up 10 sec start delay adjustment

⚠ 10 sec start delay is used in combination with an ATS panel to prevent multiple short start-stop commands coming from the ATS panel while the mains is unstable during blackout.

  1. Open the controller cover and locate the red dip switch (S-DELAY).
  2. Use your finger to move the dip switch 1 to ON position.
  3. Replace the cover and tighten screws.
Air Cleaner Check/Cleaning maintenance

⚠ Excess oil will restrict air flow and may cause engine to smoke at startup.

⚠ Operating without element or loose element allows dirt to enter engine.

  1. Remove air cleaner case lid springs and unhook tabs.
  2. Remove air cleaner cover and element.
  3. Check element and replace if damaged.
  4. Clean element in warm soapy water or non-flammable solvent, dry thoroughly.
  5. Dip filter in clean engine oil, squeeze out excess oil.
  6. Install air cleaner in reverse order of removal.
Battery Charging maintenance

⚠ Battery gives off explosive gases; keep sparks, flames, and cigarettes away.

⚠ Battery contains sulfuric acid; contact with skin or eyes may cause severe burns.

Tools: Digital multimeter, Battery charger

  1. Turn combination switch OFF.
  2. Remove battery.
  3. Check battery for damage.
  4. Leave battery for 30 minutes.
  5. Measure battery voltage with digital multimeter.
  6. If below 12.4 V, charge battery.
  7. Connect charger positive to positive, negative to negative.
  8. Leave for 30 minutes.
  9. Measure voltage; if below 12.7 V, charge.
  10. If still below 12.7 V, replace battery.
Engine Oil Change maintenance

⚠ Used engine oil contains substances that have been identified as carcinogenic. Wash hands thoroughly after contact.

  1. Drain oil while engine is warm.
  2. Place suitable container under oil drain bolt.
  3. Remove oil filler cap, oil drain bolt, and washer.
  4. Install new oil drain washer and tighten drain bolt to specified torque.
  5. Fill with recommended oil to upper level mark.
  6. Tighten oil filler cap securely.
Engine Oil Level Check maintenance
  1. Place engine on level surface.
  2. Remove oil filler cap and wipe oil level gauge clean.
  3. Insert oil filler cap without screwing in.
  4. Remove cap and check oil level on gauge.
  5. If near or below lower mark, fill to upper mark with recommended oil.
  6. Tighten oil filler cap securely.
Fuel Tank and Fuel Strainer Cleaning maintenance

⚠ Gasoline is highly flammable and explosive. Keep heat, sparks, and flame away. Handle fuel only outdoors.

  1. Drain fuel into suitable container.
  2. Remove fuel tank and fuel strainer.
  3. Clean fuel strainer and fuel tank with non-flammable solvent.
  4. Allow to dry thoroughly.
  5. Install fuel tank.
  6. Check for any signs of fuel leakage.
Spark Arrester Cleaning maintenance

⚠ If engine has been running, allow it to cool before proceeding.

Tools: Wire brush

  1. Remove two screws and spark arrester.
  2. Clean carbon deposits from spark arrester screen with wire brush.
  3. Check screen for damage; replace spark arrester if damaged.
  4. Install spark arrester in reverse order of removal.
Spark Plug Check/Adjustment maintenance

⚠ If engine has been running, allow it to cool before proceeding.

Tools: Spark plug wrench, Wire-type feeler gauge

  1. Remove spark plug cap, then spark plug using spark plug wrench.
  2. Visually check; replace if heavily fouled or insulator cracked.
  3. Measure plug gap with wire-type feeler gauge.
  4. Adjust gap by bending side electrode.
  5. Install spark plug finger-tight, then tighten 1/8 – 1/4 turn.
  6. Install spark plug cap securely.
Valve Clearance Check/Adjustment maintenance

Tools: Thickness gauge

  1. Disconnect breather hose.
  2. Remove head cover bolt and head cover.
  3. Set piston near top dead center of compression stroke.
  4. Insert thickness gauge between rocker arm and valve stem.
  5. If adjustment needed, loosen pivot adjusting nut, turn pivot to obtain specified clearance.
  6. Retighten pivot adjusting nut to specified torque.
  7. Recheck clearance.
  8. Install head cover and breather hose.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Aftermarket parts that fit this engine

3
35120-Z5T-003 FridayParts $10.90 30700-Z1C-813 KuduParts $12.00 FP-XP-0034625

Parts listed by aftermarket suppliers as fitting this engine — leads compiled from supplier catalogs; verify the exact part for your serial number.

Common questions

What is the oil capacity of the Honda GX270T2?

The Honda GX270T2 engine has an oil capacity of 1.1 liters.

Which generators use the Honda GX270T2 engine?

The Honda GX270T2 powers 1 generator set(s), including Honda EM4000SX.

What is a common problem with the Honda GX270T2 engine?

A commonly reported issue on generators using the Honda GX270T2 is: Engine speed does not stabilize. Fix: Disassemble and inspect for restricted parts. Replace or repair the main wire harness. Check for continuity between the ECM 8P connector wire harness side and junction box 8P connector wire harness side: No continuity, Normal, Abnormal, Normal..