Wheel Excavators, M323 Railroad Excavator, Cat C4.4

Wheel Excavators
M323 Railroad Excavator
M323 Railroad Excavator short tail design silhouette
M323 Railroad Excavator long tail design silhouette
M323 Railroad Excavator operators in the cab
M323 Railroad Excavator with external lights
M323 Railroad Excavator push-to-start button and controls
M323 Railroad Excavator driving in the dirt
M323 Railroad Excavator
M323 Railroad Excavator short tail design silhouette
M323 Railroad Excavator long tail design silhouette
M323 Railroad Excavator operators in the cab
M323 Railroad Excavator with external lights
M323 Railroad Excavator push-to-start button and controls
M323 Railroad Excavator driving in the dirt
Move from Road to Rail with Ease

The Cat® M323 rail excavator features a modular design with options for short-tail and long-tail configurations. The flexible drive system – tire, rail, or an innovative combination – can be switched between at the touch of a button during operation, to help ensure optimal operation in a wide variety of applications. The next generation rail excavator is purpose built for rail and is the ideal machine to help increase versatility and efficiency.

Sustainability
Specially Built for Rail Applications
        
  • Hydrostatic rail wheel drive (9A): Ideal for long distances and for traveling over rail infrastructure such as industrial plants.
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  • Classic drive with rail axles and tire drive (9C): Perfect for applications requiring high traction and pulling power, such as pulling heavy loads.
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  • Combination of both drive types (Dual 9A/9C): Combines the advantages of both systems to help offer maximum flexibility for different applications.
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  • The M323 is extremely mobile and can travel at speeds of up to 25 km/h (15 mph) on the road or 30 km/h (18 mph) on rail.
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  • With removable additional counterweight, the machine meets both the criteria for rail and road approval, while simultaneously helping increase lifting capacities and excavation performance.
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  • With the rail-specific Safe Energy Control System (ECS), machine movements can be limited vertically and sideways. Movements begin to slow down as they approach the preset limits. Movements beyond these limits are blocked.
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  • The short tail design (1575 mm or 5.2 ft) meets the specific requirements for operations around track without significantly compromising the excavator’s performance and stability. It is ideal for working in confined spaces.
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  • The long tail design (2000 mm or 6.6 ft) helps enable smooth operation with high load capacities.
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  • The adjustable boom offers an optimal combination of reach, digging force, and lifting height below the catenary wire.
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  • The rated capacity indicator (RCI) and rated capacity limiter (RCL) systems help ensure machine stability in all working positions.
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  • The cab offers optimal comfort for the driver and passenger, even during long operations, with a sophisticated lighting concept and air conditioning.
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  • The storage space has been increased by 40% to help transport track-specific accessories.
High Performance
Specially Built for Rail Applications
High Performance
        
  • The C4.4 engine meets EU Stage V emission standards.
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  • The engine responds quickly to load changes to help deliver consistently high performance – regardless of operating conditions.
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  • Designed for maximum efficiency through load-sensing hydraulics to support fast cycle times.
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  • Eco mode and automatic engine speed control help lower fuel consumption while still delivering consistent performance.
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  • The powerful and efficient Cat® C4.4 engine offers superior durability.
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  • The on-demand cooling system helps reduce fuel consumption.
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  • A dedicated swing pump also supports fuel efficiency and allows for fast and smooth combined movements.
Work in Comfort
High Performance
Work in Comfort
        
  • A high-resolution LCD monitor helps provide quick access to frequently used functions.
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  • Sensitivity can be adjusted using joysticks on both road and rail.
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  • Adjustable seats, armrests, steering column, joystick controls, buttons, and thumbwheels help enable a unique operator experience.
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  • The ergonomically designed cab features easy-to-reach controls, all located in front of you.
Maintenance
Work in Comfort
Maintenance
        
  • Routine maintenance components such as fuel and engine oil filters, and fluid access points are accessible from ground level.
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  • The automatic lubrication system on the uppercarriage and a small number of lubrication points on the undercarriage help reduce maintenance times.
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  • The axial fan and all radiators are located in a single unit. The radiators are designed for easy cleaning and can be unlocked and tilted without tools.
Versatile Solution for Rail Applications
Maintenance
Versatile Solution for Rail Applications
        
  • With standard auxiliary hydraulics, including high-pressure and quick coupler lines and circuits, attachments can be easily changed without the need for additional lines.
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  • Up to 20 different hydraulic flow and pressure settings can be saved.
Safety Features
Versatile Solution for Rail Applications
Safety Features
        
  • Rollover protective structures (ROPS) for the operator and auxiliary cabs are tested according to ISO 12117-2:2008.
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  • The Cat M323 meets all applicable safety standards, including EN 15746:2020.
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  • E-fence technology limits movement when working under power lines or near traffic.
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  • The cab includes an electric backup horn, emergency button, and machine main power switch.
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  • Intelligent devices adapted for rail and road, such as a seatbelt warning indicator, automatic swing lock, and safety lever, help enhance jobsite safety.
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  • Long handrails and access steps with anti-skid plates help provide easy and safe entry into the cab.
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  • Large glass areas, wide-angle mirrors, a large roof hatch, rear and side-view cameras, and powerful LED work lights help provide great all-around visibility.
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  • The standard integrated PIN code helps prevent unauthorized use and make theft more difficult.
Integrated Cat® Technologies
Safety Features
Integrated Cat® Technologies
        
  • Increase production and minimize operating costs with help from Cat technology solutions.
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  • VisionLinkTM technology provides a wireless connection to your jobsite and provides machine location, operating hours, fuel consumption, idle time, and event codes.
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  • The easy-to-read, high-resolution LCD monitor keeps you up-to-date with important machine information.
Sustainability
Integrated Cat® Technologies
Sustainability
        
  • The Cat C4.4 engine meets EU Stage V emission standards.
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  • Cat diesel engines are required to use ULSD (ultra-low sulfur diesel fuel with 15 ppm of sulfur or less) and are compatible* with ULSD blended with the following lower-carbon intensity fuels** up to: 20% biodiesel FAME (fatty acid methyl ester)*** or 100% renewable diesel, HVO (hydrogenated vegetable oil) and GTL (gas-to-liquid) fuels. Refer to guidelines for successful application. Please consult your Cat dealer or “Caterpillar Machine Fluids Recommendations” (SEBU6250) for details.
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  • Auto Engine Speed Control helps reduce unnecessary fuel burn and greenhouse gas emissions by allowing the engine to automatically go into idle mode when the machine is not working.
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  • VisionLinkTM displays the CO₂ emissions for monitored assets, calculated by fuel type for the Runtime Fuel Burned each day in a selected date range.

*While Caterpillar engines are compatible with these alternative fuels, some regions may not allow their use.
**Tailpipe greenhouse gas emissions from lower-carbon intensity fuels are essentially the same as traditional fuels.
***Engines with no aftertreatment devices are compatible with higher blends, up to 100% biodiesel (for use of blends higher than 20% biodiesel, consult your Cat dealer).
Specially Built for Rail Applications
Cat M323 Railroad Excavator on the rails with a bucket
Cat M323 Railroad Excavator beauty shot
Cat M323 Railroad Excavator operator looking comfortable in the cab
Cat M323 Railroad Excavator ground level maintenance check
Cat M323 Railroad Excavator with a Cat bucket
Cat M323 Railroad Excavator with external lights
Remotely manage your production targets
M323 Railroad Excavator side profile
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Engine
Engine Model Cat C4.4
Biodiesel Capability Up to B20¹
Emissions Meets EU Stage V emission standards.
Note (1) Net power advertised is the power available at the flywheel when the engine is equipped with fan, air cleaner, Clean Emission Module (CEM) exhaust gas aftertreatment, alternator, and cooling fan running at intermediate speed. Rated speed at 1,700 rpm. Advertised power is tested per the specified standard in effect at the time of manufacture.
Note (2) ¹Cat diesel engines are required to use ULSD (ultra-low sulfur diesel fuel with 15 ppm of sulfur or less) and are compatible* with ULSD blended with the following lower-carbon intensity fuels** up to: 20% biodiesel FAME (fatty acid methyl ester)*** or 100% renewable diesel, HVO (hydrotreated vegetable oil) and GTL (gas-to-liquid) fuels. Refer to guidelines for successful application. Please consult your Cat dealer or “Caterpillar Machine Fluids Recommendations” (SEBU6250) for details. *While Caterpillar engines are compatible with these alternative fuels, some regions may not allow their use. **Tailpipe greenhouse gas emissions from lower-carbon intensity fuels are essentially the same as traditional fuels. ***Engines with no aftertreatment devices are compatible with higher blends, up to 100% biodiesel (for use of blends higher than 20% biodiesel, consult your Cat dealer).
Swing Mechanism
Note (1) *For CE-marked machine default value may be set lower.
Machine Weight
Note (1) Operating weight includes full fuel tank, operator and pneumatic tires. Weight varies depending on configuration.
Dimensions
Boom Variable Adjustable Boom 5.2 m (17'1")
Stick 2.0 m (6'7")
Working Ranges and Forces
Boom Variable Adjustable Boom 5.2 m (17'1")
Stick 2.0 m (6'7")
Note (1) Range values are with 9A transmission and dual pneumatic tires (10.00-20). Range values at the stick end.
Air Conditioning System
Note The air conditioning system on this machine contains the fluorinated greenhouse gas refrigerant R134a or R1234yf. See the label or instruction manual for identification of the gas. If equipped with R134a (Global Warming Potential = 1430), the system contains 0.8 kg (1.8 lb) of refrigerant which has a CO2 equivalent of 1.144 metric tonnes (1.261 tons). If equipped with R1234yf (Global Warming Potential = 0.5), the system contains 0.8 kg (1.8 lb) of refrigerant which has a CO2 equivalent of 0.0004 metric tonnes (0.0004 tons).
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Engine
Engine Power - ISO 14396 134 kW
Engine Power - ISO 14396 (DIN) 183 hp (metric)
Net Power - ISO 9249 129 kW
Net Power - ISO 9249 (DIN) 176 hp (metric)
Bore 105 mm
Stroke 127 mm
Displacement 4.4 l
Drive
Maximum Travel Speed - Road Mode 25 km/h
Maximum Travel Speed - Rail Mode 30 km/h
Hydraulic System
Main System - Maximum Flow - Implement 306 L/min
Maximum Pressure - Implement Circuit - Normal 35000 kPa
Maximum Pressure - Implement Circuit - Heavy Lift 37000 kPa
Maximum Pressure - Implement Circuit - Travel Circuit 35000 kPa
Swing Mechanism
Maximum Swing Speed* 9 r/min
Maximum Swing Torque 52 kN·m
Machine Weight
Operating Weight Maximum 24300 kg
Operating Weight Minimum 21700 kg
Service Refill Capacities
Fuel Tank 240 l
Diesel Exhaust Fluid (DEF) 19 l
Cooling System 30 l
Hydraulic Tank 116 l
Hydraulic System - Including Tank 270 l
Dimensions
Shipping Height - Top of Cab 3209 mm
Shipping Length 8921 mm
Support Point 4234 mm
Working Ranges and Forces
Maximum Cutting Height 8741 mm
Maximum Digging Depth 3247 mm
Maximum Reach at Ground Line 7345 mm
Stick Forces (ISO) 83 kN
Bucket Forces (ISO) 117 kN
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NOTE
BOOM AND STICK
UNDERCARRIAGE AND STRUCTURES
  • - Long or Short radius counterweight
  • - Removeable counterweight for road regulation
  • - Hydrostatic (9A), Friction (9C) or combined (9A and 9C) transmission
  • - Road and Rail travel speed
  • - Access step
  • - Lifting points
  • - Tie-down points
  • - Tires
HYDRAULIC SYSTEM
  • - Joystick with sliders and push buttons
  • - Adjustable hydraulic sensitivity
  • - Dedicated swing pump
  • - Pump for the drive and implement
  • - Programmable flow and pressure for up to 20 attachments
  • - 1x High Pressure Line (HP) and 1x Medium Pressure Line (MP)
SERVICE AND MAINTENANCE
  • - Ground-level fuel and engine oil filters and fluid taps
  • - Ground-level fuel refueling
  • - Centralized lubrication for undercarriage
  • - Auto-lubrication system
SAFETY AND SECURITY
  • - Emergency stop button
  • - Safety decals for rail certification
  • - Insulated or Non insulated wheels
  • - Rail suspensions for 9A transmission
  • - ROPS cab for operator and rail agent
  • - Stick lowering control valve (SLCV) and boom lowering control valve (BLCV) including overload warning device
  • - Bucket lowering control valve (BLCV)
  • - Safe ECS monitor - Set the limit/monitor the load
CAB
  • - Premium or Deluxe cab
  • - Travel pedal (1-way or 2-way)
ENGINE
  • - Cat C4.4 Twin Turbo
  • - Altitude 3000 m (9,842 ft) capability without derating
  • - Mechanical air compressor
ELECTRICAL SYSTEM
  • - Rescue pump
  • - Camera, Rear and Right Hand (RH) side
  • - 9 working lights (1800 LM or 4200 LM)
  • - Wiper
  • - Speed Road and Rail (country regulation)
  • - Product Link™ (Global System for Mobile [GSM] or satellite)
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NOTE
UNDERCARRIAGE AND STRUCTURES
  • - Rail wheel Stone shield protection and Work Tools (WT) support
  • - Towing coupler (manual or automatic)
  • - Rail coupler
  • - Rail towing bar
  • - Tire pressure monitoring
  • - Tire inflator, blow gun
  • - 1M track gauge kit
HYDRAULIC SYSTEM
  • - Drain line
  • - Return line 25.4 mm (1")
  • - 2nd HP
  • - Bio hydraulic oil
  • - Bio oil micro-filtration unit
SERVICE AND MAINTENANCE
SAFETY AND SECURITY
  • - Air braking system for rail cars or trailers
  • - Ground area proximity light
  • - People detect system
  • - Bird view camera
  • - Access light
ELECTRICAL SYSTEM
  • - 5 working lights (1800 LM or 4200 LM)
  • - Refueling pump
  • - UIC certified rail lights
  • - Travel alarm
  • - Beacon
  • - Electric plug at the stick-end (permanent and switch actuated)
  • - Electrical plug at the lower frame
  • - Anti theft system