Need the factory service data for your Yanmar ViO27-2 or ViO35-2 excavator? This 584-page service manual covers both machines: hydraulic circuits, electrical systems, undercarriage, engine internals, and the components that fail hardest in the field. Inside: full hydraulic circuit schematics with pressure adjustment procedures, wiring diagrams for the complete electrical system, torque tables covering machine and engine fasteners, and a full troubleshooting section that addresses both non-breakdown symptoms and root-cause diagnosis. You also get step-by-step teardown procedures for the hydraulic pump, control valve, swing motor, and travel motor. Replace the fuel filter element every 200 hours and match any hose to SAE J517, 100R1 at 0.25-inch (6.3 mm) inner diameter. Factory numbers, not estimates. Your machine is down. Get the right spec on the first try. Bookmarked by section; search any torque value or schematic by keyword, on laptop or tablet.
What's Inside This Yanmar ViO27-2, ViO35-2 Manual
| System | Pages | Key Topics |
|---|---|---|
| General Cautions for Maintenance Work | 8-19 | Correct Work, Safety Precautions, Preparations, Cautions for Disassembly and Reassembly, Cautions for Removal and Installation of Hydraulic Equipment |
| Technical Data | 20-48 | Specifications, Outline Drawing and Working Area (Canopy Type, Cabin Type), Weight List of Main Parts, Lifting Capacity List |
| Service Standards | 49-78 | Machine Performance, Engine, Undercarriage (Rubber Crawler Specifications, Steel Crawler Specifications, Common Specifications of Steel & Rubber Crawlers), Controls |
| Engine | 79-121 | Measurement, Inspection, Adjustment, Reassembly Procedures for Engine Components |
| Hydraulic System | 122-165 | Circuit Outline, Hydraulic Circuit Schematic, Circuit Operation, Pressure Adjustment |
| 6-1 Hydraulic Pump | 167-226 | Removal and Reinstallation, Disassembly and Reassembly, Torque Specs, Three Bond Adhesive Application |
| 6-2 Control Valve | 227-276 | Spool Operation, Removal and Reinstallation, Disassembly and Reassembly, Relief Valve Adjustment |
| 6-3 Pilot Valve | 277-286 | Removal and Reinstallation, Disassembly and Reassembly, Pilot Pressure Specs |
| 6-4 Swing Motor | 287-319 | Removal and Reinstallation, Disassembly and Reassembly, Relief Valve, Swing Speed Verification (10 RPM) |
| 6-5 Travel Motor | 320-404 | Removal and Reinstallation, Disassembly and Reassembly, Speed Change Valve, Travel Motor Relief |
| 6-6 Pilot Check Valve (Quick Coupler Type) | 405-412 | Removal and Installation, Quick Coupler Hydraulic Circuit, Pilot Check Valve Disassembly |
| Adjustment and Repair | 413-536 | Electrical Equipment of Machine and Engine, Undercarriage, Controls, Swing Bearing, Hydraulic Equipment, Work Implements, Cabin |
| Periodic Inspection and Servicing | 537-539 | Periodic Inspection Schedule, Service Intervals, Filter Replacement Intervals |
| Fuel, Lube Oil and Grease Recommended | 540-541 | Fuel Specification, Engine Oil Grade, Hydraulic Oil Grade, Grease Type Recommendations |
| Troubleshooting | 542-581 | Non-Breakdown Symptoms, Root-Cause Troubleshooting for Hydraulic, Electrical and Mechanical Faults |
| Reference Data | 582-583 | Specifications for Attachment, Boom and Arm Dimensional Reference |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| ViO27-2 | ||
| Fuel filter filtration area | 67.0 (432) sq.in. (sq.cm) | p. 26 |
| Fuel filter filtration accuracy | 150 Meshes | p. 24 |
| Air cleaner filtration area | 9.7 (0.9) sq.ft. (sq.m) | p. 26 |
| Overall length (Transportation position) | 162.6 in. | p. 21 |
| ViO35-2 | ||
| Air cleaner filtration area | 9.7 (0.9) sq.ft. (sq.m) | p. 33 |
| Overall length (Transportation position) | 180.9 in. | p. 28 |
| All Models | ||
| Hydraulic hose (SAE J517, 100R1) Inner dia. (Hose dia. 02) | 0.25 (6.3) in. (mm) | p. 15 |
| Hydraulic hose (SAE J517, 100R1) Outer dia. (Hose dia. 02) | 0.53 (13.5) in. (mm) | p. 15 |
| Minimum ground clearance | 12.6 in. | p. 21 |
| Swing speed | 10 rpm | p. 22 |
| Hydraulic oil tank capacity | 11.1 Gals | p. 24 |
| Intake valve clearance (Cold engine) | 0.0079 in. | p. 26 |
Yanmar ViO27-2, ViO35-2 Common Problems This Manual Covers
Yanmar ViO27-2 and ViO35-2 boom or stick functions become weak or stop under load
Inspect the main relief valve and control spools for wear or sticking. Verify the hydraulic hose working pressure for size 02 lines does not exceed 2489 PSI (17.2 MPa) as noted on page 15. Drain and replace the hydraulic fluid if you find heavy contamination.
Manual Section: Control Valve TroubleshootingUpperstructure swing motor fails to rotate or turns slowly when the control lever is engaged
Test the swing speed to verify it reaches 10 rpm as specified on page 22. Inspect the pilot lines and swing motor relief valve for sticking spools. Measure the pilot pressure at the test port. Rebuild or replace the swing motor if internal leakage exceeds allowable limits.
Manual Section: Swing Motor TroubleshootingEngine starts hard, stalls frequently, or runs rough when operating in cold weather conditions
Drain the water separator daily to prevent fuel contamination. Replace the fuel filter element every 200 hrs as directed on page 539. Measure the intake valve clearance on a cold engine and adjust it to 0.0079 in. Check page 26 for exact valve train measurement procedures.
Manual Section: Engine Measurement, Inspection, Adjustment, and ReassemblyHydraulic oil level drops repeatedly or visible external fluid leaks appear around the boom cylinders p. 49
Inspect all visible hydraulic lines and cylinder rod seals for damage. Tighten hose clip 25 and 35 to a torque of 2.89 to 3.62 ft·lbf (3.92 to 4.9 N·m) using the chart on page 76. Replace any worn O-rings or cracked hoses immediately to stop fluid loss.
Manual Section: Service StandardsFrequently Asked Questions
What are the torque specs for the hydraulic pump mounting bolts on Yanmar ViO27-2?
For the Yanmar ViO27-2, the hydraulic pump installation bolts (M12) should be tightened to a torque of 57.9 to 72.3 ft·lbf (78.5 to 98.1 N·m). Apply Three Bond 1324 or equivalent adhesive to the bolts.
What are the replacement specifications for the Air filter on Yanmar ViO27-2/ViO35-2?
The air cleaner filtration area is 9.7 sq.ft. (0.9 sq.m) for both ViO27-2 and ViO35-2. Inspect and replace the air filter element per the periodic inspection schedule (Section 8-1).
How often should I replace the fuel filter element on the Yanmar ViO27-2?
Replace the fuel filter element per Section 8-1. The fuel filter is a filter paper type with automatic air release, filtration area 67.0 sq.in. (432 sq.cm). Replace every 200 hours or per the periodic maintenance schedule.
What is the correct swing speed specification for the Yanmar ViO27-2 and ViO35-2?
The specified swing speed for both the ViO27-2 and ViO35-2 is 10 rpm. If swing speed falls below this, inspect the swing motor relief valve and pilot lines for sticking spools or internal leakage.
Can I download and print this manual?
Yes. This is a PDF manual — download immediately after purchase and print any section you need in the shop. The file is fully searchable and bookmarked by section for quick navigation.
Reviews
There are no reviews yet.