Komatsuengine(no series)

Komatsu S6D105-1ZZ(S/N 91468-UP)

Maintenance schedule, common problems & OEM parts breakdown

The Komatsu S6D105-1ZZ engine (S/N 91468-UP) is a six-cylinder, turbocharged diesel powerplant belonging to the S6D105 series. It is primarily fitted to Komatsu GD530A/AW motor graders (the OEM part reference-Up) and certain PC200-3/PC200LC-3 excavators. The engine delivers approximately 170 hp (127 kW) and 550 lb-ft (745 Nm) of torque. It operates within a weight class range of 9,182 to 87,083 lb depending on the host machine configuration. The S6D105-1ZZ succeeded earlier S6D105-1 variants and was eventually replaced by the S6D105-1E and S6D105-1C series as emissions standards tightened. Configurations offered include mechanical fuel systems and various turbocharger setups tailored for grading and excavation duties.

Across the S6D105 generation, changes focused on refining fuel injection precision and integrating electronic monitoring while retaining mechanical robustness. The S6D105-1ZZ remains significant in the used and parts market because it powers high-volume, durable machines like the GD530A grader and PC200-3 excavator. Its widespread use ensures a strong aftermarket supply of cylinder kits, piston sets, and gaskets. The engine's mechanical simplicity compared to newer electronic-only designs makes it a preferred candidate for rebuilds and inframe overhauls, sustaining its value in the secondary market.

Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.

Komatsu S6D105-1ZZ(S/N 91468-UP) specifications

Engine

ModelS6D105-1ZZ
SeriesS6D105 Series
Displacement6.5 L (396 cu. in.)
Cylinders6
AspirationTurbocharged
Fuel SystemDirect injection
Gross Power170 hp (127 kW)
Net Power170 hp (127 kW)
Torque550 lb-ft (745 N·m)
Emissions TierNot documented for this exact serial range — verify with your dealer

Weights

Operating WeightNot documented for this exact serial range — verify with your dealer
Shipping WeightNot documented for this exact serial range — verify with your dealer
Ground PressureNot documented for this exact serial range — verify with your dealer

Dimensions

Transport LengthNot documented for this exact serial range — verify with your dealer
Transport WidthNot documented for this exact serial range — verify with your dealer
Transport HeightNot documented for this exact serial range — verify with your dealer
Track GaugeNot documented for this exact serial range — verify with your dealer
Ground ClearanceNot documented for this exact serial range — verify with your dealer

Performance

Travel SpeedNot documented for this exact serial range — verify with your dealer
GradeabilityNot documented for this exact serial range — verify with your dealer
Dig DepthNot documented for this exact serial range — verify with your dealer
Lift CapacityNot documented for this exact serial range — verify with your dealer

Service capacities (summary)

Engine Oil Refill CapacityNot documented for this exact serial range — verify with your dealer
Cooling System CapacityNot documented for this exact serial range — verify with your dealer
Hydraulic System CapacityNot documented for this exact serial range — verify with your dealer
Fuel Tank CapacityNot documented for this exact serial range — verify with your dealer

Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.

Komatsu S6D105-1ZZ(S/N 91468-UP) maintenance schedule

Service intervalTasks
Every 10 h
  • Check engine oil level and condition.
  • Check hydraulic fluid level via sight glass.
  • Check coolant level and ensure cap is secure.
  • Check fuel level and drain water separator.
  • Check DEF level on Tier 4 machines.
  • Check air filter restriction indicator.
Every 250 h
  • Change engine oil and filter.
  • Grease all points (boom, stick, bucket, swing bearing).
  • Check fluid levels.
  • Check air filter element.
  • Inspect belts and hoses.
  • Perform visual walk-around.
Every 500 h
  • Replace fuel filter.
  • Replace hydraulic return filter.
  • Perform battery service and load test.
  • Test coolant SCA.
  • Collect KOWA oil sample.
  • Perform detailed undercarriage inspection.
Every 1,000 h
  • Collect hydraulic oil sample.
  • Change final drive oil.
  • Inspect turbocharger.
  • Check valve adjustment.
  • Perform structural inspection.
  • Measure undercarriage wear.
Every 2,000 h
  • Change hydraulic oil.
  • Flush and replace coolant.
  • Service transmission.
  • Perform comprehensive component evaluation.
  • Check KDPF.
  • Replace worn belts, hoses, and clamps.

Servicing the S6D105-1ZZ(S/N 91468-UP) beyond the schedule

Predictive Maintenance & Fluid Analysis

Utilize KOWA fluid analysis at every major service interval to monitor wear metals (iron, copper, lead, aluminum) and contaminants (silicon, sodium) in the S6D105-1ZZ engine oil. Check hydraulic fluid particle count and viscosity to detect pump wear early. Test coolant pH, SCA concentration, and glycol content to prevent corrosion in the engine block. Monitor DEF levels daily on Tier 4 applications to ensure SCR system efficiency. Track KOMTRAX telematics data for load frequency and fault codes to anticipate component failures before they cause downtime.

Corrective & Common Repairs

Address intermittent starting or random shutdowns by inspecting the engine controller power supply and sensor wiring on the S6D105-1ZZ. Replace worn fuel injectors if power loss or excessive fuel usage occurs. Fix hydraulic hose cracks and leaks during daily walk-arounds to prevent fluid loss. Replace air filter elements when the restriction indicator triggers. Inspect and replace worn belts and clamps during the 2,000-hour service. Check for coolant leaks around the water pump and thermostat housing, common failure points in this series.

Overhaul & Rebuild Points

Perform inframe overhauls on the S6D105-1ZZ using piston kits (e.g., 6137-32-2130) and ring sets when compression drops or oil consumption increases. Replace cylinder liners and bearings during major rebuilds. Inspect the turbocharger for shaft play and seal leaks at the 1,000-hour interval. Check valve clearances and adjust if necessary to maintain performance. Replace the cylinder head gasket if coolant contamination or combustion gas leakage is detected. Ensure all fasteners are torqued to factory specifications during reassembly.

Seasonal & Environment Servicing

Select engine oil viscosity based on ambient temperature charts in the Operation and Maintenance Manual to ensure proper lubrication in extreme cold or heat. Check the cooling system for debris buildup in the radiator and oil cooler fins before winter or dusty seasons. Drain the fuel water separator daily in humid or cold conditions to prevent freezing. Inspect the air intake system for dust accumulation in arid environments. Verify battery charge and terminal condition in cold weather to ensure reliable starting. Flush the cooling system annually to remove sediment and maintain heat exchange efficiency.

S6D105-1ZZ(S/N 91468-UP) common service parts

Part numberPart
07281-00197Clamp,(With Pre-Fuel Filter)Check fitment →
6127-61-2971O-Ring,Oil Cooler ElementCheck fitment →
6136-61-2190O-Ring,Oil Cooler ElementCheck fitment →
6136-61-2290Gasket,Oil Cooler ElementCheck fitment →
600-651-1411Element,Oil CoolerCheck fitment →

Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.

S6D105-1ZZ(S/N 91468-UP) fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
CA115Engine crankshaft speed sensor and backup speed sensor failureBroken sensor, wiring issue, or connector corrosionReplace the speed sensor and verify the voltage at the pin connector
CA111Internal engine controller faultECM hardware failure or corruptionReplace or reprogram the ECM
CA451Common rail pressure sensor feedback value too highMalfunction in the rail sensor or actual overpressure conditionDiagnose the fuel rail pressure sensor or pump lines
CA441Battery voltage too lowWeak battery or charging system failureReplace the battery or alternator and check the voltage regulator
CA442Battery voltage too highAlternator overcharging or regulator failureReplace the alternator or battery and check the voltage regulator
CA234Engine overspeedThrottle calibration error, engine load cycle issue, or operator misuseVerify throttle calibration and engine load cycle
CA122Intake air pressure sensor feedback voltage too highSensor malfunction or wiring issueVerify the intake pressure sensor and wiring
CA123Intake air pressure sensor feedback voltage too lowSensor short or airflow restrictionCheck for a sensor short or an airflow restriction
CA153Intake air temperature sensor feedback voltage too highSensor malfunctionReplace or test the IAT sensor
CA154Intake air temperature sensor feedback voltage too lowSensor malfunctionReplace or test the IAT sensor

Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.

S6D105-1ZZ(S/N 91468-UP) attachments & work tools

Crawler Excavator Attachments

The S6D105-1ZZ engine (S/N 91468-Up) powers the GD530A/AW-2A/2B/2C motor grader series, not a crawler excavator. Excavator applications for the S6D105-1ZZ are not documented in the provided sources; excavator models like the PC200-3 utilize the S6D105-B-1 engine variant.

Motor Grader Blade Configurations

The GD530A/AW-2A/2B/2C series utilizes a moldboard blade with a typical width of 3.7 meters (12 ft 2 in) to 4.0 meters (13 ft 1 in) for this class. The blade is mounted via a standard grader circle or A-frame hitch system, allowing for 360-degree rotation and lateral shift.

Motor Grader Ripper/Scarifier

Rear-mounted ripper or scarifier attachments are available for the GD530A/AW-2A/2B/2C series to break hard ground. These tools are hydraulically controlled and mounted to the rear frame, requiring auxiliary hydraulic lines from the main valve to operate the lift and depth cylinders.

Hydraulic System Requirements

Work tools requiring hydraulic power utilize Komatsu hydraulic oil (HO) or equivalent. The engine drives the main hydraulic pump, which supplies flow to the grader circle, blade cylinders, and optional rear ripper circuits. Fluid capacity and pressure ratings vary by specific machine configuration.

Engine Guarding and Options

Factory configurations for the GD530A/AW-2A/2B/2C series include standard engine guarding such as heavy-duty air filters and oil coolers suitable for dusty environments. Specific guarding options like extended life coolant (ELC) or specialized exhaust systems are determined by the machine's emission tier and operating region.

All S6D105-1ZZ(S/N 91468-UP) assemblies by section

Every catalogued assembly group for the Komatsu S6D105-1ZZ(S/N 91468-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

Accessory
Komatsu : S6d105-1zz(S/N 91468-Up) : Accessory : Air Compressor
61***20Air Compressor Ass'Y1
DK***20Connecting Rod A1
DK***00Bearing2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Accessory : Air Compressor And Mounting
01***20Bolt,(Sandy? Dusty Terrain Spec.)2
01***25Bolt,(Sandy? Dusty Terrain Spec.)4
01***95Bolt,(For Reversible Fan)2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Accessory : Air Compressor Piping
07***12Gasket,(Without Air Compressor Type) (K1)6
07***16Gasket,Air Compressor Piping1
07***15Plug,(Used When Without Heater)1
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Cooling System
Komatsu : S6d105-1zz(S/N 91468-Up) : Cooling System : Corrosion Resistor And Piping
01***25Bolt,(Sandy? Dusty Terrain Spec.)4
01***20Bolt, Hose Clamps (Inlet And Return Line Hoses)4
01***29Washer,Spring (Cold Weather Spec.)4
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cooling System : Water Pump And Cooling Fan
01***16Bolt,(For Slag Handling)2
01***30Bolt,(Cold Terrain Spec.)3
01***55Bolt,(For Suction? Reversible Fan)2
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Cylinder Block
Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Camshaft And Tappet
01***25Bolt,(Without Auto Priming System)2
01***20Bolt,(Forwarded Individually Parts)2
01***25Washer,Spring?(Sandy And Dusty Spec.)2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Crankshaft
01***25Bolt - Rear Guard Mounting6
01***45Bolt,Nylock1
01***25Bolt,L.H. (For Add. Air Compressor)6
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Cylinder Block
01***30Bolt,(For France Noise Suppression)4
01***25Bolt, Mount Engine Oil Drain To Fuel Tank4
01***30Washer,Spring(Sandy?Dusty Terrain S.)4
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Flywheel And Flywheel Housing
01***40Bolt,(Dust And Dirt Protection)9
01***60Bolt, Trunnion Cap2
01***35Screw6
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Front Cover And Gear
01***22Bolt,(Cold Terrain Spec.)4
01***25Bolt,(Without Auto Priming System)4
01***60Bolt,(Without Alternator Bracket)10
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Oil Pan
01***12Bolt,(Without R.P.C.U.)3
01***22Bolt,(Cold Terrain Spec.)28
01***25Bolt,(Without Auto Priming System)8
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Block : Piston And Connecting Rod
04***18Ring, Retaining12
61***40Crank Pin Metal A6
61***02Connecting Rod Ass'Y,(B)6
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Cylinder Head
Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Air Cleaner
08***01Indicator,Dust (Japanese-English)1
08***01Indicator,Dust Indicator1
09***61Plate? Instruction,(Japanese-English) (Not Shown)1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Air Intake Manifold And Connection
01***50Bolt,(For Trimming Dozer)2
01***65Bolt,(For Alternator Bracket Mount)10
01***70Bolt3
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Cylinder Head
01***25Bolt,(Sandy? Dusty Terrain Spec.)2
01***20Bolt, Hose Clamps (Inlet And Return Line Hoses)2
01***30Washer,Spring(Sandy?Dusty Terrain S.)2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Cylinder Head Cover
07***23Clamp - Hose1
07***00Clip1
07***30Clip1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Exhaust Manifold And Turbocharger
01***00Bolt (M10-1.50x100)10
01***15Bolt2
01***00Bolt (M10-1.50x100)10
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Muffler And Mounting
01***16Bolt,(For Slag Handling)2
01***20Bolt,(Large Capacity Type) (Std)2
01***16Bolt, Mount Solenoid Valve2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Rocker Arm
01***80Bolt,(Shim 5 Pieces Over)2
01***06Nut, Regular Hexagon (M8-1.25)12
01***36Washer,Radio Controlled Slag Handling6
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Komatsu : S6d105-1zz(S/N 91468-Up) : Cylinder Head : Turbocharger
61***00Turbocharger Ass'Y,(T04b-59)1
GA***00Clamp3
GA***01Bolt6
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Electrical System
Komatsu : S6d105-1zz(S/N 91468-Up) : Electrical System : Alternator (35a)
60***20Alternator A. (35a)1
KD***57Bearing,Ball? Front1
KD***80Collar1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Electrical System : Alternator And Mounting (35a)
01***45Bolt,(For Suction? Reversible Fan)1
01***35Bolt,(Cold Weather Spec.)1
01***40Bolt,(Shim 3-Piece)1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Electrical System : Starting Motor (7.5kw)
60***50Starting Motor Ass'Y,(7.5kw)1
KD***60Shift Lever Assembly1
KD***40Spring,Spring4
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Komatsu : S6d105-1zz(S/N 91468-Up) : Electrical System : Starting Motor And Mounting (7.5kw)
01***35Bolt - Torque Converter Totransmission Mounting3
01***30Bolt, Mounting - Front Hand Rails3
01***36Washer,Radio Controlled Slag Handling3
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Engine Kit
Komatsu : S6d105-1zz(S/N 91468-Up) : Engine Kit : Gasket Kit
07***18O-Ring,(See Fig.1601-29?1602-17)1
07***70O-Ring,(For Intake Air Cover)1
07***00O-Ring,(F4350-65a1 -5 )1
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Fuel System
Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Filter And Piping
01***25Bolt,(Sandy? Dusty Terrain Spec.)2
01***35Bolt, Mounting - Flywheel Housing End2
01***20Bolt, Hose Clamps (Inlet And Return Line Hoses)2
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump (Coupling)
DK***00Bolt1
DK***00Washer,Lock2
DK***00Coupling,Cross1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump (Feed Pump)
DK***20Bolt, Joint1
DK***20Pump,Priming1
DK***20Housing1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump (Governor) (1/2)
DK***00Adapter1
DK***00Governor Ass'Y1
DK***80Nut1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump (Governor) (2/2)
DK***80Shim? 0.5mm0
DK***00Washer,Spring1
DK***00Spring1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump (Pump)
61***30Injection Pump Ass'Y1
DK***10Washer,Spring1
DK***30Bearing0
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Injection Pump And Piping
01***70Bolt4
01***20Bolt,(Large Capacity Type) (Std)2
01***35Bolt, Mounting - Flywheel Housing End5
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Komatsu : S6d105-1zz(S/N 91468-Up) : Fuel System : Fuel Nozzle And Spill Pipe
01***55Bolt,(For Trimming Dozer)12
01***55Screw12
01***25Washer,Spring?(Sandy And Dusty Spec.)12
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Lubricating Oil System
Komatsu : S6d105-1zz(S/N 91468-Up) : Lubricating Oil System : Lubricating Oil Cooler
01***25Bolt,(Without Auto Priming System)4
01***30Bolt,(Cold Terrain Spec.)4
01***35Bolt,(Without Auto Priming System)15
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Komatsu : S6d105-1zz(S/N 91468-Up) : Lubricating Oil System : Lubricating Oil Filter And Mounting
01***95Bolt1
01***35Bolt, Mounting - Flywheel Housing End1
01***25Bolt (M10x1.50x25)1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Lubricating Oil System : Lubricating Oil Pump And Suction Pipe
01***25Bolt,(Without Auto Priming System)3
01***30Bolt,(Cold Terrain Spec.)1
01***45Bolt,(S6d155-4b)1
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Komatsu : S6d105-1zz(S/N 91468-Up) : Lubricating Oil System : Turbocharger Lubricating Oil Piping
01***22Bolt,(Cold Terrain Spec.)2
01***35Bolt, Mounting - Flywheel Housing End2
01***20Bolt,(Forwarded Individually Parts)2
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S6D105-1ZZ(S/N 91468-UP) serial number reference

The PIN plate is riveted to the right-hand side of the cab on the lower frame, typically just behind the front idler or beneath the operator's window. The prefix is the model code (e.g., GD530A) found on the plate, followed by the serial number range.

PrefixIdentifies
GD530A/AW-2A/2B/2CMotor Grader / Wheel Loader

Frequently asked questions

What engine does the Komatsu S6D105-1ZZ (S/N 91468-UP) use?

It uses the Komatsu S6D105-1ZZ, a six-cylinder, turbocharged, direct-injection diesel engine delivering approximately 170 hp (127 kW) and 550 lb-ft (745 Nm) of torque.

What is the operating weight of machines using this engine?

Operating weight varies by configuration and host machine. For the GD530A/AW motor grader (S/N the OEM part reference-Up) and PC200-3/PC200LC-3 excavators, weights range from approximately 9,182 lb to 87,083 lb depending on attachments and counterweights.

What replaced the Komatsu S6D105-1ZZ engine?

The S6D105-1ZZ was succeeded by the S6D105-1E and S6D105-1C series engines as Komatsu updated its powertrain lineup to meet stricter emissions standards and improve performance.

What S6D105-1ZZ(S/N 91468-UP) owners discuss

What are the known powertrain and hydraulic behaviors for the Komatsu S6D105-1ZZ engine series?
The S6D105-1ZZ engine delivers 170 horsepower and 550 lb-ft of torque. It utilizes a turbocharged aspiration system with direct injection fuel delivery. The engine is designed to drive hydraulic pumps that are sensitive to engine speed; if the hydraulic pump fails, the engine is often damaged shortly thereafter. The machine operates smoothly and is noted for high fuel efficiency compared to earlier generation competitors. Hydraulic performance is closely tied to engine RPM, and a drop in engine speed under load often indicates hydraulic system overload or engine power loss rather than a pure hydraulic fault. All hydraulic functions slowing simultaneously points to shared supply, pump control, or engine performance issues, while single-function weakness requires circuit-specific diagnosis of valves, cylinders, or pilot controls. Hydraulic weakness that appears only when hot suggests internal leakage in pumps, main control valves, or motors due to decreased oil viscosity at operating temperature. The engine relies on Komatsu EO, TO, and AXO fluid specifications for proper lubrication and cooling system protection. Have your dealer verify the exact hydraulic pressure settings for your specific machine configuration.
What undercarriage and wear patterns are typical for machines equipped with this engine?
Machines with this engine series are subject to significant wear on bushings, bearings, and track pads due to continuous load and environmental exposure. Worn bushings lead to increased noise and vibration, while degraded bearings can cause premature track failure. Track tensioners are prone to leakage and require regular inspection; seal kits for these tensioners are a common maintenance item. Undercarriage components should be monitored for mud or debris packing, which affects travel speed and track tension. The line is generally designed to wear out complete machines simultaneously, contributing to lower resale values when major components fail. Aftermarket undercarriage parts are available, but genuine Komatsu parts are significantly more expensive. Have your dealer verify the current undercarriage wear percentage and track tensioner seal condition.
What are the specific quirks or maintenance requirements for the S6D105-1ZZ engine series?
The S6D105-1ZZ engine (Serial Number 91468-Up) is part of the 6D105 series. It requires Komatsu genuine oil filters; using non-OEM filters like Donaldson has been reported to cause the oil diversion warning light to stay on for 5-10 minutes, though this may also be related to oil change timing. The engine uses a specific arrangement of fittings that resemble JIC fittings but have different angles, requiring specialized tools for service. Coolant system cleaning requires stopping the machine on level ground and adding Komatsu corrosion resistor agent K1. The engine oil refill capacity varies by ambient temperature and specific engine model variant within the series. Regular inspection of the cooling package, including the radiator, hydraulic oil cooler, and charge-air cooler, is critical as material packed between heat exchangers can cause overheating even if the exterior appears clean. Have your dealer verify the correct coolant type and oil viscosity grade for your operating environment.
What are the common electrical and sensor issues reported for this machine type?
Komatsu excavators rely heavily on electronic control systems, meaning a single faulty sensor or unstable power supply can trigger multiple warning signals. Common electrical issues include intermittent starting, dashboard failure, and random machine shutdowns. These symptoms often stem from battery condition, poor engine or chassis grounds, or faulty connectors. A battery may show acceptable voltage until the starter is loaded; a load and voltage-drop test is recommended before replacing the starter. Multiple fault codes often indicate battery, ground, or connector issues rather than component failure. The oil diversion warning light may stay on for several minutes if non-OEM filters are used. Have your dealer verify the integrity of all engine and chassis ground connections and the battery load capacity.
What should be checked when buying a used machine with the S6D105-1ZZ engine (S/N 91468-Up)?
When purchasing a used machine with this engine, verify the exact serial number prefix to confirm the engine model and configuration. Check the engine data plate on the left side of the engine block for the model name and serial number. Inspect the cooling system for material packed between the heat exchangers. Test the hydraulic system cold and hot to identify viscosity-related leakage. Check the track tensioner seals for leakage and inspect the undercarriage for worn bushings and bearings. Verify the battery condition under load. Check for any history of hydraulic pump failure, as this often damages the engine. Confirm the use of genuine Komatsu filters to avoid warning light issues. Have your dealer verify the engine serial number matches the machine frame serial number and check for any outstanding technical service bulletins.
How does the S6D105-1ZZ engine differ from related variants like the S6D102E-1?
The S6D105-1ZZ engine (Serial Number 91468-Up) is a distinct model from the S6D102E-1 series. The S6D105-1ZZ is part of the 6D105 series, while the S6D102E-1 is part of the 6D102 series. These engines have different displacements, power outputs, and internal components. The S6D105-1ZZ delivers 170 horsepower and 550 lb-ft of torque. Parts and service procedures are not interchangeable between these series. Always confirm the engine model and serial number before ordering parts or performing service. Have your dealer verify the exact engine model and serial number to ensure correct parts and service procedures are used.
What are the fluid specifications and capacities for the S6D105-1ZZ engine?
The S6D105-1ZZ engine requires Komatsu EO, TO, and AXO fluid specifications. The engine oil refill capacity varies by ambient temperature and specific engine model variant within the series. The coolant system requires Komatsu Super Coolant AF-NAC or equivalent with corrosion resistor agent K1. The hydraulic system uses Komatsu hydraulic oil specifications. The exact oil and coolant capacities are not specified in the general sources for this exact serial range and vary by configuration. Have your dealer verify the exact fluid capacities and specifications for your specific machine configuration.

Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.

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