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Kohler KDI 1903TCR Engine

The Kohler KDI 1903TCR is a 1.86 L 3-cylinder turbo+ charge after cooler engine rated at 1800 rpm, producing up to 34.9 kW. It powers generator sets from Kohler, including the 30 REOZK4, 35 REOZT4 and KDI 1903 TCR. It holds 8.9 L (2.4 gal) of oil and 4.2 L (1.1 gal) of coolant.

Also known as: Kohler KDI 1903TCR

Part of the Kohler KDI1903 engine family — 8 variants share parts & fitment.

1.861 L
Displacement
3
Cylinders
1800 rpm
Rated speed
34 kW
Gross power

Engine specifications

Oil capacity8.9 L
Coolant capacity4.2 L
Displacement1.861 L
Cylinders3
AspirationTurbo+ Charge After Cooler
Rated speed1800 rpm
Gross power34 kW

Common problems

15
  • Warning YELLOW light turn on
    Cause: Engine ECU has detect a malfunctions
    Fix: Contact REHLKO authorised workshops
  • Warning RED light turn on
    Cause: Engine ECU has detect a malfunctions
    Fix: Contact KOHLER authorised workshops
  • The engine starts but stops
    Cause: Inefficient electrical connections
    Fix: Clean the electrical contacts
  • The engine does not start
    Cause: Sulphated battery terminals corroded
    Fix: Clean the battery terminals
  • The engine does not rev up
    Cause: Inefficient electrical connections
    Fix: Clean the electrical contacts; if the problem persists, Contact REHLKO authorised workshops
  • Slow acceleration
    Cause: Clogged fuel filter
    Fix: Replace the fuel filter
  • RPM instability at idle speed
    Cause: Clogged fuel pipes
    Fix: Contact REHLKO authorised workshops
  • Poor quality fuel
    Fix: Clean the tank and refuel with quality fuel
  • Numero dei giri al minimo basso
    Cause: Clogged fuel pipes
    Fix: Contact KOHLER authorised workshops
  • Low idle speed
    Cause: Clogged fuel pipes
    Fix: Contact REHLKO authorised workshops
  • Excessive fuel consumption
    Cause: Clogged air filter
    Fix: Replace with a new filter
  • Engine starts but stops
    Cause: Inefficient electrical connections
    Fix: Clean the electrical contacts
  • Engine overheats
    Cause: Insufficient coolant level
    Fix: Fill up to the level
  • Engine lost its initial performance
    Cause: Clogged air filter
    Fix: Replace with a new filter
  • Engine jerking
    Cause: Clogged fuel pipes
    Fix: Contact REHLKO authorised workshops

Compiled from service & troubleshooting documentation across every generator set that uses the Kohler KDI 1903TCR.

Maintenance schedule

ItemSpecCapacityPart #Interval
Air filter—1000 hr
Fuel filter—250 hr
Oil filterCJ-4 Low S.A.P.S, CK-4 Low S.A.P.S, CJ-4 Low S.A.P.S, CK-4 Low S.A.P.S, CI-4 Plus, CI-4, CH-4—1000 hr
Batterystandby—
Belt—1000 hr
Coolant—250 hr
OilSAE 10w-30 (-25°C ÷ +40°C)8.9 lt.ED0053029490250 hr Amazon eBay
Spark plug—1000 hr

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

Service intervals

8
ItemActionHoursMonthsNotes
oilChange500 hrMinimum 500 hours oil change interval
Alternator V beltReplace36 moIn case of low use: 36 months (Tab. 4.2 footnote 3)
CoolantReplace24 moIn case of low use: 24 months (Tab. 4.2 footnote 4)
Engine oilChange12 moIn case of low use: 12 months (Tab. 4.2 footnote 1)
Fuel filter cartridgeReplace12 moIn case of low use: 12 months (Tab. 4.2 footnote 1)
Oil filter cartridgeReplace12 moIn case of low use: 12 months (Tab. 4.2 footnote 1)
Paralleling boxInspect12 moAnnually by a Kohler authorized distributor/dealer, or when wear, damage, deterioration, or malfunction is evident or suspected.
Paralleling box internal componentsInspect1 moMonthly or when a condition noticed during external inspection may have affected internal components; enclosure cover must be removed by trained personnel.

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
TypeItemValueUnitCondition
ClearanceAlternator standard belt deflection at point p<10mmapprox. 10 kg force
OtherAlternator standard belt tension force350-450Nusing DENSO BTG-2 or similar
OtherEngine speed adjustment50default setting; settings between 40 and 60 acceptable; 52 increases speed by 2 RPM, 49 decreases by 1 RPM
OtherGenerator to bus phase angle-10 to 10degreesverify with contactor closed
OtherMaximum inclination during operation30° max. 30 minutesdegreeeven in combined
OtherMaximum inclination during operation35° max 1 minutedegree
OtherReactive droop1%default setting; range 0.5 - 2%
SpeedAlternator Poly-V belt tension at point p149-196Hz
SpeedAlternator standard belt tension at point p80-85Hz
TorqueAlternator belt fastening bolts B and C40Nm
TorqueFuel filter cartridge17Nm
TorqueLifting screws/eyebolts25Nm
TorqueOil drain plug35Nm
TorqueOil filter cover25Nm
TorquePGEN terminal block connections0.5Nm
TorquePGEN terminal block connections4.4in. lbs.
TorqueWater presence sensor5Nm
VoltageController measurement accuracy2%without calibration; requires a calibrated multimeter for calibration

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
Coolant50% ethylene glycol + 50% water or 50% propylene glycol + 50% waterBASF G05/G30/G33/G34/G40/G48/G50; VW G13/G12++; ARTECO XLC/XLI/LONG LIFE COOLANT/FREECOR SPC/FREECOR DSC; TEXACO AFC/XLC; REVKOGEL 2000; PARAFLU F02; CCI LLC L255A/LLC A432Antifreeze mixture
Engine oilSAE 5W-30 / 10W-40API CJ4; ACEA E6-E9; Low S.A.P.S.7.5 LKDI 1903 TCR; max level including oil filter; standard version
FuelDieselEN 590; ASTM D975-09B; S15; No.1 or No.2 low sulfur or ultra low sulfur dieselBiodiesel B10 max 10% methyl ester; do not use vegetable oil. For ambient below 0°C use suitable low-temperature fuel.
FuelNo 1 Diesel (US) - ASTM D 975-09 B - Grade 1-D S 15 and No 2 Diesel (US) - ASTM D 975-09 B - Grade 2-D S 15, S 500 for mechanical models onlyASTM D 975-09 B

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

Procedures

12
Alternator standard belt tension check and setting adjustment

⚠ Check belt tension only when engine is off.

Tools: DENSO BTG-2 or similar belt tension tool, torque wrench

  1. Check belt A condition; replace if worn out or deteriorated.
  2. Check at point p that tension is between 80 and 85 Hz.
  3. Using DENSO BTG-2 or similar tool F, check corresponding value is between 350 and 450 N.
  4. If no tool, apply approx. 10 kg force at point p; movement must be less than 10 mm.
  5. If not correct, loosen fastening bolts B and C.
  6. Pull alternator outwards in direction D to tension belt.
  7. Tighten bolts B and C in sequence with torque wrench E at 40 Nm.
  8. Check tension again; let engine run and cool, repeat adjustments if out of range.
Calibration adjustment

⚠ Copying personality profiles from one controller to another can overwrite calibration coefficients and requires re-calibration.

Tools: Calibrated multimeter with recent calibration verification

  1. Use a calibrated multimeter to measure the generator voltage and enter the correct value in the CONTROLLER CONFIG -> CALIBRATION screen.
  2. Use a calibrated multimeter to measure the bus voltage and enter the correct value in the CONTROLLER CONFIG -> CALIBRATION screen.
Verify Generator Operation diagnostic

⚠ Generators must all operate at the same frequency, voltage, and phase connection in order to parallel.

Tools: SiteTech software

  1. Ensure the load is not connected or is drawing less power than a single generator can provide.
  2. Navigate to CONTROLLER CONFIG -> COMMUNICATION SETUP and verify PGEN Nodes Online indicates the correct number of nodes.
  3. Verify alternator connection (voltage selector switch position), system voltage, and voltage regulator target on each generator.
  4. Start a single generator by pressing the Run button; the paralleling box contactor should close and the Generator Connected to Bus indicator should light.
  5. Verify bus and generator voltages match and generator to bus phase angle is between -10 and 10 degrees.
  6. Verify the load bus is energized and available at the load.
  7. Stop the generator by pressing the OFF button; the contactor should open.
  8. Repeat for each generator in the paralleling system.
Verify Paralleling and Load Sharing diagnostic

Tools: Load bank (optional)

  1. Place all generators in automatic mode by pressing the Auto button; verify the red shutdown indicator is not illuminated.
  2. Provide a local start request by holding AUTO, pressing RUN, releasing RUN, then releasing AUTO.
  3. Verify all generators start, one generator closes its contactor, and the others synchronize and close their contactors.
  4. Verify that the % of rated power of the generators matches, showing the generators are sharing load equally.
  5. If a load bank is available, test the system under load.
Control Harness Connections installation

⚠ The control harness connections for GEN 1 and GEN 2 must correspond to the source camlock cable connections.

  1. Connect the control harness from the generator set connected to the GEN 1 camlock connectors to GEN 1 CONTROL.
  2. Connect the control harness from the generator set connected to the GEN 2 camlock connectors to GEN 2 CONTROL.
  3. When not used, store the control harnesses on the storage rack inside the enclosure.
Grounding installation

⚠ Grounding electrical equipment: hazardous voltage can cause severe injury or death. Turn off the main circuit breakers of all power sources before servicing.

  1. Connect the ground lug on the paralleling box to earth ground according to applicable state and local codes.
  2. Follow NEC guidelines for grounding electrical equipment.
  3. The neutral is bonded to ground inside the paralleling box; if required, remove the bonding bus to disconnect neutral from ground.
Load Connections installation

⚠ Multiple power sources can automatically energize the distribution bus. Disconnect all power sources before connecting to the distribution bus.

  1. Remove the camlock security guard from one row of connectors for each generator and store the guard.
  2. Connect the load side ground (green) camlock cables to the distribution bus and then to the paralleling box.
  3. Connect the load side neutral (white) camlock cables to the distribution bus and then to the paralleling box.
  4. Connect the load side L1 (black), L2 (red), and L3 (blue) camlock cables to the distribution bus and then to the paralleling box.
Multiple Paralleling Boxes (PGEN Connections) installation
  1. Connect one or two generators to each paralleling box.
  2. Use Belden cable #9841 (or equivalent) shielded twisted-pair communication cable to connect the PGEN terminal blocks on the paralleling boxes.
  3. Tighten the connections to 0.5 Nm (4.4 in. lbs.).
Paralleling System Setup installation

⚠ Generator management must be disabled manually at each generator set controller.

Tools: Personal computer with SiteTech software

  1. Check that the voltage selector switch and/or alternator wiring matches the building voltage configuration for all generator sets.
  2. Set the digital output to Contactor (SiteTech Programmable Digital Output 116).
  3. Set reactive droop to 0.5-2% (default 1%), using the same reactive droop setting on all generators.
  4. Set the target voltage on all paralleled generators to the same value.
  5. Set engine speed adjustment to 50 on all generators (default 50; range 40-60).
  6. Verify metering; if voltage is incorrect, use the calibration procedure.
  7. Set Sync Mode in AUTO to ACTIVE and Sync Mode in Run to CHECK on all generators.
  8. Set Generator Management Enabled to OFF at each generator unless generator management is requested.
  9. Set up load management (load shed priorities) for non-critical loads.
  10. Stop all generators by pressing the OFF button on each controller.
Source Connections installation

⚠ Hazardous voltage. This equipment must be installed and serviced by qualified electrical personnel. Do not connect or disconnect cables under load.

  1. Remove the camlock security guard from one row of connectors for each generator and store the guard.
  2. Generator 2 connects to the upper set of camlocks; generator 1 connects to the lower set.
  3. Connect the source side ground (green) camlock cables to the paralleling box first and then to each generator.
  4. Connect the source side neutral (white) camlock cables to the paralleling box first and then to each generator.
  5. Connect the source side L1 (black), L2 (red), and L3 (blue) camlock cables to the paralleling box first and then to each generator.
Air filter cartridge replacement maintenance
  1. Release two fastenings F of cover A.
  2. Remove cartridges B and G.
  3. Reinstall new cartridges B and G.
  4. Reinstall cover A and check right tightness of fastenings F.
Air filter check maintenance

⚠ Do not use compressed air.

Tools: damp cloth

  1. Release two clasps F of cover A.
  2. Remove cartridges B and G.
  3. Remove cap C.
  4. Clean inside components A, C, and D with a damp cloth.
  5. Do not use compressed air; repeatedly tap front side E on a flat surface.
  6. When cartridge G is dirty, do not clean it but replace cartridges B and G.
  7. Reinstall cartridges G and B, cap C, and cover A; check clasps F tightness.

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

Parts cataloged across the Kohler KDI1903 family

40
Part #DescriptionCategory
100-025-000Air FilterAir filter
401-2567Cartridge dry-type air filterAir filter
A-226955Air cleaner assemblyAir filter
ED161816KDI AIR FILTER DONALDSON 7” WITH SAFETY CARTRIDGEAir filter
GM16944Element, air cleanerAir filter
GM66601Element, InnerAir filter
100-075-000BeltBelt
401-2571Alternator belt (standard alternator)Belt
401-2572Poly-V alternator belt (heavy environmental condition)Belt
401-2573Poly-V alternator belt (standard condition)Belt
100-060-000Coolant FilterCoolant filter
401-2574Coolant (OAT)Fluid
401-2575Coolant (HOAT)Fluid
100-045-000Fuel FilterFuel filter
ED161817KIT FUEL FEEDING PUMP WITH PRE-FILTERFuel filter
ED161820KIT SECONDARY FEUL FILTER (WIF+CS+HEATER)Fuel filter
ED0082051340-SCOV.HEAD GASK.-OR SET 1903 TCRGasket
ED0082051360-SCOV.HEAD GASK.-OR SET 1903 MGasket
ED161746KIT AIR GRID HEATER + GASKETS (FOR LOW TEMPERATURES)Gasket
401-2568Intake manifold hose (air filter - intake manifold)Hose
401-2569Coolant hosesHose
401-2570Fuel line hoseHose
GM22310Hose, ReducerHose
GM88850Hose, Air Intake (Item 5)Hose
100-030-000Oil FilterOil filter
ED161799KIT REMOTE OIL FILTER (KDI 1903TCR ONLY)Oil filter
401-2576ATS (Engine)Service part / kit
ED00530294902.5 Blue smokeService part / kit
ED0072455190CONTROL PANEL KDI-TCR STAGE VService part / kit
ED161789KIT CAB HEATER PROVISIONService part / kit
ED161815KDI M - VEHICLE WIREHARNESSService part / kit
ED161818KDI COUNTER CONNECTOR ACCESSORIESService part / kit
ED161821KDI TCR VEHICLE HARNESS (2186-499)Service part / kit
ED161822KDI BATTERY HARNESS (2186-406)Service part / kit
ED161823KIT THROTTLE CONTROL PEDAL + COUNTER CONNECTORService part / kit
ED161824KIT THROTTLE CONTROL KNOB + COUNTER CONNECTORService part / kit
ED161825KIT THROTTLE CONTROL LEVER + COUNTER CONNECTORService part / kit
273377Gauge, restrictionSensor
ED161819KIT COUNTER CONNECTOR WATER IN FEUL SENSORSensor
100-090-000Spark PlugSpark plug

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Aftermarket parts that fit this engine

11

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 Kohler KDI 1903TCR?

The Kohler KDI 1903TCR engine has an oil capacity of 8.9 liters.

What is the displacement of the Kohler KDI 1903TCR?

The Kohler KDI 1903TCR has a displacement of 1.861 liters with 3 cylinders.

Which generators use the Kohler KDI 1903TCR engine?

The Kohler KDI 1903TCR powers 3 generator set(s), including Kohler 30 REOZK4, Kohler 35 REOZT4, Kohler KDI 1903 TCR.

How often should you change the oil in the Kohler KDI 1903TCR?

The Kohler KDI 1903TCR oil change interval is every 250 hours.

What is a common problem with the Kohler KDI 1903TCR engine?

A commonly reported issue on generators using the Kohler KDI 1903TCR is: Warning YELLOW light turn on. Cause: Engine ECU has detect a malfunctions. Fix: Contact REHLKO authorised workshops.