Part of the Yanmar Repair Manuals.
Pull the valve cover on the 2TNE68-EFW and you have two numbers to get right before it runs again: 0.15 to 0.25 mm of intake valve lash on a cold engine, and a healthy cylinder should still pull 470 PSI at 250 rpm. Both figures come from this Yanmar service manual for the C12R(EP) crawler carrier, publication 131103, and guessing at either one is how a quiet diesel becomes a smoky one.
The 221 page PDF covers the whole machine around that engine: service standards and tightening torques, hydraulic cylinders, tank and piping, wiring diagrams with circuit descriptions for starting and charging, periodic servicing charts, and a troubleshooting chapter. Engine work gets its own chapter, from compression testing through cylinder head, piston, crankshaft and governor measurement.
It is bookmarked for navigation, downloads immediately after purchase, and prints cleanly, so the pages that matter can sit on the bench and get dirty.
What's Inside This Yanmar C12R(EP) Manual
| System | Pages | Key Topics |
|---|---|---|
| General Cautions for Maintenance Work | 9-22 | Correct Work, Safety Precautions, Preparations, Cautions for Disassembly and Reassembly, Cautions for Removal and Installation of Hydraulic Equipment |
| Technical Data | 23-34 | Specifications, Machine Dimensions, Hydraulic Circuit Schematic, Wiring Diagram, Weight of Components |
| Service Standards | 35-50 | Machine Performance, Engine, Undercarriage, Control Devices, Hydraulic Cylinder, Work Implement, List of Tightening Torque (Machine) |
| Engine | 51-96 | Measurement |
| Structure and Operation | 97-110 | Electrical Equipment of Machine (Parts Layout of Electrical Equipment, Monitor and Alarm Systems, Wiring Diagram, Circuit Description of Engine Start and Stop, Circuit Description of Battery Charging) |
| Hydraulic Equipment | 111-146 | Hydraulic Cylinder, Hydraulic Oil Tank, Hydraulic Piping |
| Structure and Operation | 147-198 | Electrical Equipment, Undercarriage, Control Equipment, Power Transmission, Hydraulic Equipment, Wagon |
| Periodic Inspection and Servicing | 199-202 | Lube Oil, Hydraulic System, Undercarriage, Steering Equipment, Electric Equipment, Fuel, Cooling Water, Rubber Hose |
| Fuel, Lube Oil and Grease Recommended | 203-206 | Engine Oil, Transmission Oil, Hydraulic Oil, Fuel, Engine Cooling Water, Fuel Tank, Cooling System |
| Troubleshooting | 207-219 | Machine and Engine, H.S.T., Fuel System, Cooling Water System, Cylinder Head, Piston, Starter Motor, Battery |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Engine \u00d7 Engine mount tightening torque | 44.1 to 58.8 ft\u2022lbf (4.5 to 6.0 N\u2022m) | p. 48 |
| Engine mount vibroisolating rubber Nut M12 tightening torque | 32.6 to 43.5 ft\u2022lbf (44.1 to 58.9 N\u2022m) | p. 48 |
| Hydraulic oil type | YANMAR SUPER HYDRO OIL (ISO VG46) | p. 205 |
| Hydraulic oil system prescribed amount | 4.36 Gals. (16.5 L) | p. 205 |
| Fuel filter filtration area | 66.96 sq.in. (432 sq.cm) | p. 27 |
| LO filter filtration area | 124.0 sq.in. (800 sq.cm) | p. 27 |
| Air cleaner type | Cyclone type | p. 28 |
| Air cleaner filtration area | 4.7 sq.ft. (0.44 sq.m) | p. 28 |
| Hydraulic hose installation tightening torque (valve piping) | 16.6 to 20.3 ft\u2022lbf (22.5 to 27.4 N\u2022m) | p. 142 |
| HST (High) relief set pressure | 3959 to 4002 PSI (27.4 to 27.7 MPa) | p. 25 |
| HST (Low) relief set pressure | 58 to 87 PSI (0.4 to 0.6 MPa) | p. 25 |
Yanmar C12R(EP) Common Problems This Manual Covers
Hard starting and low compression
A 2TNE68-EFW that cranks but will not light usually comes down to compression or valve lash. The manual gives the compression test procedure, the 470 PSI at 250 rpm standard, and the cold intake valve clearance of 0.15 to 0.25 mm, so you set lash to the book instead of by ear.
Manual Section: Chapter 4 Engine p. 51Machine will not travel straight
After a hose swap or an oil change, air trapped in the H.S.T. system leaves the carrier pulling to one side or creeping unevenly. The air release procedure in this chapter walks through bleeding the circuit properly before you condemn a pump.
Manual Section: Chapter 1 General Cautions for Maintenance Work p. 9Leaking hydraulic cylinders and fittings
Weeping cylinder seals and seeping fittings drop the oil level until travel and dump response go soft. This chapter covers the hydraulic cylinders, oil tank and piping runs, and the service standards give a cylinder nut torque of 217 to 253 ft-lbf so reassembly is not a guess.
Manual Section: Chapter 6 Hydraulic Equipment p. 111Engine will not crank or charge
When the key does nothing or the battery keeps going flat, the fault usually sits in the start, stop or charging circuits. This chapter lays out the electrical parts layout, the wiring diagram, and circuit descriptions for engine start and stop and battery charging, so you can trace it wire by wire.
Manual Section: Chapter 5 Structure and Operation p. 97Overheating and coolant loss
A radiator cap that will not hold its rated 12.8 PSI, or a thermostat that never opens at 157.1 to 162.5 degrees F, will cook a small diesel fast. The engine chapter includes the cooling water system and radiator leak check alongside those standards, so you test parts instead of swapping them.
Manual Section: Chapter 4 Engine p. 51Loose track roller and sprocket hardware
Roller, idler and carrier roller nuts back off under vibration, and pulling them tight by feel invites a sheared stud. The tightening torque list gives the figures: 115.7 to 123.0 ft-lbf for the roller and idler nuts, 123.0 to 151.9 ft-lbf for the sprocket bolts.
Manual Section: Chapter 3 Service Standards p. 35Faults you cannot pin down
Some symptoms, a hunting idle, a warning lamp, sluggish travel, do not point at any one component. The troubleshooting chapter maps symptoms to likely causes across the engine, electrical and hydraulic systems, so you test in a sensible order rather than replacing parts on a hunch.
Manual Section: Chapter 10 Troubleshooting p. 207Frequently Asked Questions
Which machine and engine does this manual cover?
It covers the Yanmar C12R(EP) crawler carrier and its 2TNE68-EFW diesel engine, rated 10.3 HP (7.7 kW) at 2800 rpm. The carrier itself is covered alongside the engine: the hydraulic oil type and the system prescribed amount are on page 205. This is the Yanmar service manual, publication number 131103, in English.
Does it include engine rebuild measurements and clearances?
Yes. The Engine chapter covers compression testing, valve clearance adjustment and fuel injection timing, then measurement procedures with service data for the cylinder head, cylinder block, pistons and rings, connecting rods, camshaft, crankshaft, gears and governor mechanism. p. 51
Are wiring diagrams included?
Yes. The Technical Data chapter includes the wiring diagram and hydraulic circuit schematic, and the Structure and Operation chapters add the electrical parts layout plus circuit descriptions for engine start and stop and battery charging. p. 23
Where do I find torque specs?
The Service Standards chapter carries the machine tightening torque list, from the engine mount bolts at 44.1 to 58.8 ft-lbf down to hose clips and battery clamps, with the track roller, idler and sprocket figures in the same table. p. 35
What format is this manual in?
A 221-page Service Manual in searchable PDF format, available the moment you complete checkout. View on computer, tablet, or phone, with no shipping wait.
Can I print specific sections of this Service Manual?
No restrictions at all. Print individual pages, full chapters, or the entire manual. The PDF is completely unlocked.
Can I find wiring schematics in this Yanmar C12R(EP) manual?
Yes. The wiring diagram is on page 32, printed alongside the hydraulic circuit schematic in the Technical Data chapter, and the electrical parts layout with the engine start and stop circuit descriptions follows in the Structure and Operation chapters. There is no separate connector-pinout chapter beyond that.
Reviews
There are no reviews yet.