Komatsu PC27MR-2, PC30MR-2, PC35MR-2, PC40MR-2, PC50MR-2 Shop Manual – SEBM032410

Description

Komatsu PC27MR-2 through PC50MR-2 Shop Manual – SEBM032410

This is the shop manual released by Komatsu for the PC27MR-2, PC30MR-2, PC35MR-2, PC40MR-2 and PC50MR-2 mini excavators, issued under document number SEBM032410. It is the bench reference used in a service workshop when a machine needs to be diagnosed, adjusted, torn down or rebuilt, and it covers the five models across the full range of their major systems.

File Details

• Manual type: Shop Manual
• Brand: Komatsu
• Models covered: PC27MR-2, PC30MR-2, PC35MR-2, PC40MR-2, PC50MR-2
• Document number: SEBM032410
• Language: English
• File format: PDF
• Page count: 621 pages

Serial Number Coverage

• PC27MR-2 — 15001 and up
• PC30MR-2 — 20001 and up
• PC35MR-2 — 5001 and up
• PC40MR-2 — 8001 and up
• PC50MR-2 — 5001 and up

Engines Referenced in This Manual

• PC27MR-2 — 3D82AE-5M
• PC30MR-2 — 3D84E-5N
• PC35MR-2 — S3D84E-5PBA and 3D88E-5P
• PC40MR-2 and PC50MR-2 — 4D88E-5X

The manual notes that engine details are covered in the separate 68E-88E Series Engine Shop Manual.

Chapters Covered

• 01 General — Specification Dimension Drawing, Working Range Drawing, Specifications, Weight Table, Lubricants, Fuel and Coolant Specifications
• 10 Structure, Function and Maintenance Standard — hydraulic pump, valve assembly, PC valve, LS valve, CLSS, control valve, swing circle, swing machinery, swing motor, track frame, idler, recoil spring, track roller, carrier roller, sprocket, track shoe, road liner, triple grouser shoe, hydraulic tank, cyclone assembly, center swivel joint, travel motor, hydraulic cylinders, PPC valve, solenoid valve, control relief valve, pressure compensation valve, merge-divider valve, logic valve, LS bypass plug, monitor system, sensors, air conditioner, tilt floor, engine control and electric control system
• 20 Testing and Adjusting — standard value tables for engine and chassis related parts, engine speed, exhaust gas color, valve clearance, compression pressure, engine oil pressure, fuel injection timing, alternator and air conditioner belt tension, fuel control lever, track shoe tension, swing circle bearing clearance, work equipment / travel / boom swing / swing / blade oil pressures, LS differential pressure, PC valve, control circuit oil pressure, control pump circuit oil pressure, solenoid valve output pressure, PPC valve output pressure, swing holding brake release pressure, travel deviation, cylinder oil leakage, air bleeding, residual pressure release, tilt floor operation and diode inspection
• 30 Disassembly and Assembly — fuel injection pump assembly, radiator and hydraulic oil cooler assembly, engine and hydraulic pump assembly, track shoe assembly, idler assembly, recoil spring assembly, track roller assembly, carrier roller assembly, center swivel joint assembly, floor frame assembly, swing motor and swing machinery assembly, work equipment assembly, revolving frame assembly, swing circle assembly, control valve assembly, hydraulic cylinder assembly, air conditioner unit assembly, operator’s cab glass and front window assembly
• 90 Others — hydraulic circuit diagrams and electrical circuit diagrams for each model group

What This Shop Manual Gives You

Running the PC27MR-2, PC30MR-2, PC35MR-2, PC40MR-2 or PC50MR-2 without a proper reference makes every job longer than it needs to be. This manual removes the guesswork. The General chapter gives you the specification dimension drawings, working range drawings and weight tables for each model, plus the lubricants, fuel and coolant requirements with ambient temperature charts. The Structure, Function and Maintenance Standard chapter walks through how each assembly works and what to check against, from the variable displacement piston pump and its PC and LS valves, through the control valve spools, pressure compensation valves, merge-divider valve and logic valve, out to the swing motor, travel motor, center swivel joint, undercarriage components, cylinders and PPC valves.

The Testing and Adjusting chapter is where the manual becomes really practical. It includes the standard value tables for engine and chassis related parts — high and low idle speeds, compression pressure, blow-by pressure, oil pressure, fuel injection timing, valve clearance — and then the field procedures: how to measure main relief pressure for the work equipment, travel, boom swing, swing and blade circuits, how to read LS differential pressure, how to adjust the PC valve, the PPC valve, the main relief valves and the swing motor safety valve, and how to measure control circuit oil pressure and solenoid valve output pressure. There are step-by-step procedures for bleeding air from the pump, cylinders, swing motor and travel motor, and for releasing residual pressure from the hydraulic circuit and hydraulic tank before opening anything up.

The troubleshooting sections are split by system: E-mode for the electrical system, H-mode for hydraulic and mechanical faults, M-mode for the monitor panel and S-mode for the engine. Each entry pairs a reported symptom with a presumed cause, a standard value in normalcy and a reference for judging good or no good — useful when a machine will not start, will not swing, travels off line, loses power, or shows a warning on the monitor panel.

Disassembly and Assembly covers removing and reinstalling the major assemblies and rebuilding the sub-assemblies: the idler, recoil spring, track roller, carrier roller, center swivel joint, swing motor and swing machinery, hydraulic cylinders, control valve, swing circle and the air conditioner unit. Where a special tool is required, the manual lists it and, in many cases, sketches it so you can understand what the tool has to do before you look for one. Tightening torques, coating materials, grease types and oil quantities are given at the points where they matter.

Finally, the Others chapter collects the hydraulic circuit diagrams and the electrical circuit diagrams, split by model group and, where relevant, by page half for the larger electrical drawings. These are the drawings you want open when a fault is electrical and the wiring needs tracing rather than the pump being opened.

Who This Manual Suits

This is a working document for anyone servicing a Komatsu MR-2 series mini excavator: an owner-mechanic doing their own repairs, a workshop technician taking on a machine outside the dealer network, or a fleet maintenance team that needs the correct relief pressures, torque values and disassembly order on hand. Because one document covers PC27MR-2, PC30MR-2, PC35MR-2, PC40MR-2 and PC50MR-2, it is also useful for anyone working across more than one size in the same yard — though it is worth checking the serial number range and the engine fitted to your particular machine against the lists above before relying on a torque or pressure figure.

Repairs and Diagnoses This Manual Supports

• Setting engine idle speeds, valve clearance, fuel injection timing and fuel control lever travel
• Measuring and adjusting main relief, swing relief, boom swing relief, blade relief and travel relief pressures
• Adjusting the PC valve, LS valve and PPC valve when speed, power or fine control is off
• Tracing electrical faults through the E-mode troubleshooting tables and the electrical circuit diagrams
• Diagnosing travel deviation, swing overrun, hydraulic drift, cylinder leakage and time lag
• Removing and rebuilding hydraulic cylinders, swing machinery, center swivel joint, travel motor, idler, recoil spring, track roller and carrier roller
• Setting track shoe tension and measuring swing circle bearing clearance
• Bleeding air and releasing residual pressure correctly before opening the hydraulic system

Why the Correct Procedures and Specifications Matter

On a compact excavator, pressures and clearances are tight and the consequences of getting them wrong show up quickly — a relief valve set too high, a piston nut torqued to the wrong figure, or air left in a circuit after a rebuild can turn a straightforward repair into a repeat failure. This manual gives the target values, the tolerances and the adjustment method for the systems it covers, which is what separates a repair that holds from one that comes back.

Delivery

IMAGES PREVIEW

The file is delivered as an instant PDF download after purchase. There is no shipping and nothing to wait for. You can open it on a laptop, tablet or phone in the workshop, print the pages you need for the job in front of you, and keep the rest of the manual on file for the next machine. Because the whole PC27MR-2 through PC50MR-2 range sits in one document, you only need this single PDF on the shelf to cover all five models.