Market Position:
Essential technical resource for owners, operators, and maintenance technicians of Mitsubishi K15, K21, and K25 gasoline engine forklift trucks, serving industries requiring reliable material handling equipment.
Key Features:
Detailed step-by-step repair instructions, extensive troubleshooting charts, comprehensive wiring diagrams, accurate technical specifications, component identification, and maintenance schedules.
Competitive Alternatives:
Competes with industrial forklifts from brands like Toyota, Nissan (now UniCarriers), Caterpillar, Komatsu, Hyster, and Yale from the same production era.
Systems Covered:
Engine (K15, K21, K25 gasoline), Fuel System, Ignition System, Cooling System, Lubrication System, Exhaust System, Power Train, Transmission, Drive Axle, Steering System, Braking System, Hydraulic System (Lift, Tilt, Steering), Electrical System, Chassis, Mast Assembly, Operator Compartment, Safety Features.
Procedures Included:
Routine Maintenance, Scheduled Servicing, Troubleshooting Guides, Diagnostic Procedures, Repair Procedures, Component Overhaul, Disassembly and Reassembly, Electrical Schematics, Wiring Diagrams, Torque Specifications, Tightening Sequences, Parts Replacement, Technical Adjustments, Performance Tuning (as applicable).
Technical Depth:
Comprehensive; covers everything from basic preventative maintenance to complete engine rebuilds and complex system diagnostics.
Diagnostic Tools:
Covers diagnostic procedures using standard tools and techniques, without reliance on specialized electronic scan tools typical of modern vehicles.
Electrical System Coverage:
Includes detailed troubleshooting of starting system, charging system, lighting circuits, and hydraulic control circuits.
Hydraulic System Coverage:
Comprehensive coverage of the main hydraulic pump, control valve, lift/tilt cylinders, steering cylinder, and associated hoses and fittings.
File Format:
Digital (typically PDF, but may vary based on provider)
Print Quality:
High-resolution, optimized for digital viewing and printing. Includes clear diagrams and illustrations.
Binding Type:
Digital download - no physical binding. If printed, would typically be spiral-bound or perfect-bound for durability in a workshop environment.
Engine Types:
Mitsubishi K15, K21, K25 Gasoline Engines
Power Output Range:
Typically in the range of 30-50 HP (Horsepower), specific output varies by exact model and configuration.
Torque Output Range:
Specific torque figures are not readily available without exact engine variant, but sufficient for forklift operations, typically peaking at lower RPM.
Fuel Delivery:
Carbureted or Fuel Injected (depending on specific engine variant and year).
Carburetor Details:
If carbureted, it will involve specific models and adjustments covered in the manual.
Engine Block Material:
Cast Iron (common for this era and type of engine)
Cooling System Type:
Water-cooled with a radiator, fan, water pump, and thermostat.
Ignition Type:
Distributor-based ignition system with spark plugs (typically for models of this era).
Number Of Cylinders:
Typically 4 cylinders for these models.
Displacement Range:
Likely in the 1.5L to 2.5L range, corresponding to model designations.
Engine Family Notes:
These engines are known for their reliability and simplicity, making them easy to maintain with proper procedures.
Transmission Type:
Automatic (Torque Converter with Planetary Gearset) or Manual Transmission, depending on forklift configuration.
Transmission Fluid Specification:
ATF Dexron II/III or equivalent, consult manual for specific part numbers and capacities.
Optional Transmission Types:
While automatic is common, some configurations may have offered manual transmissions. Consult specific model details.
Transmission Features:
Forward and reverse selection, typically with a two-speed or single-speed range.
Operating Weight:
Varies significantly based on specific forklift model, mast type, and attachments. Typically ranges from 2000 kg to 4000 kg.
Lifting Capacity:
K15: ~1500 kg (3300 lbs), K21: ~2100 kg (4600 lbs), K25: ~2500 kg (5500 lbs) – actual capacity varies by configuration and load center.
Fork Length:
Typically 1070 mm or 1220 mm (42" or 48").
Tire Type:
Solid rubber or pneumatic tires, depending on application and model. Tire size and ply rating are critical and specified in the manual.
Wheelbase:
Varies by model, typically 1.5-1.8 meters.
Overall Length:
Varies greatly by model and mast configuration. Typically 2-3 meters without forks.
Overall Width:
Varies by model, typically 1-1.5 meters.
Mast Type:
Various mast types including Duplex (2-stage) and Triplex (3-stage) masts with corresponding lift heights and lowered heights. Details will be specific to the forklift model covered.
Fork Width:
Standard fork width is typically 125 mm (5 inches).
Passive Safety Features:
Operator Overhead Guard (OHG), Seatbelts, Load Backrest Extension (LBR), Mast Vibration Dampening.
Active Safety Features:
Brake Systems (e.g., hydraulic drum or disc brakes), Parking Brake, Warning Lights, Backup Alarms (often optional or added).
Safety Certifications:
Designed to meet relevant ANSI/ASME or international safety standards for forklift trucks (specific certifications depend on region and manufacturing year).
Infotainment Features:
Basic operator controls and instrumentation. Typically includes hour meter, fuel gauge, temperature gauge, oil pressure warning light, battery charge warning light, and control levers for lift, tilt, and drive.
Driver Assistance Features:
Limited; focus is on mechanical and hydraulic systems. May include power steering assist. No electronic driver assistance systems like ABS or traction control found on modern vehicles.
Connectivity Features:
None (not applicable to this type of industrial equipment).
Routine Maintenance Intervals:
Daily Checks (fluids, tires, controls), 50-Hour Checks (lubrication, filter inspection), 250-Hour Checks (oil change, filter replacement, brake inspection), 500-Hour Checks (hydraulic fluid change, transmission fluid check, engine tune-up), Annual Service. Specific intervals are detailed within the manual.
Engine Oil Type:
API Service SG, SH, SJ or higher; SAE 10W-30 or 10W-40 (check manual for specific viscosity based on ambient temperature).
Coolant Type:
Ethylene glycol based antifreeze/coolant with corrosion inhibitors. Typically a 50/50 mix with distilled water.
Hydraulic Fluid Type:
ISO VG 32 or 46 hydraulic fluid (check manual for specific viscosity and type, e.g., anti-wear hydraulic oil).
Common Issues:
Wear and tear on lift chains and cylinders, hydraulic seal leaks, carburetor or fuel injection system issues (common in gasoline engines of this era), ignition system faults, brake wear, cooling system leaks (radiator, hoses).
Common Wear Items:
Brake pads/linings, steer axle components, tilt cylinder seals, mast rollers, drive motor brushes (if applicable).
Engine Oil Capacity:
Approximately 4-5 liters (consult manual for exact capacity of K15, K21, K25 engines).
Transmission Fluid Capacity:
Approximately 6-10 liters (varies significantly by transmission type). Consult manual.
Hydraulic Fluid Capacity:
Approximately 15-25 liters (varies by mast and attachment configuration). Consult manual.
Coolant Capacity:
Approximately 8-12 liters (varies by radiator size). Consult manual.
Engine Oil Filter Pn:
Specific part numbers are critical and should be cross-referenced from the manual or dealer based on the exact engine serial number. Examples of aftermarket equivalents might exist, but original or equivalent is recommended.
Fuel Filter Pn:
Varies by engine and fuel system type. Consult manual for specific PN.
Hydraulic Filter Pn:
Varies by hydraulic system configuration. Consult manual for specific PN.
Transmission Filter Pn:
If equipped with a filter, consult manual for specific PN.
Brand Heritage:
Mitsubishi Heavy Industries (MHI) is a globally recognized manufacturer with a long history of producing robust and reliable industrial equipment, including forklifts.
Model Evolution:
The K-series forklifts represent a lineage of dependable internal combustion engine (ICE) forklifts from Mitsubishi, designed for general material handling applications. The K15, K21, and K25 designations typically refer to load capacity (e.g., 1.5, 2.1, 2.5 tons).
Production Period:
These models likely fall within the late 1980s to early 2000s production era, reflecting common forklift technology of that time.
Manufacturing Location:
Likely manufactured in Japan or at Mitsubishi's overseas production facilities.
