Part of the Yanmar Repair Manuals.
Feeler gauge in hand at the rocker cover of a 3TNA72L, you want Yanmar's own clearance in front of you, not a forum guess. This service manual puts the factory servicing standards for the C20R crawler carrier and its 3TNA72L-UFW diesel into 34 tightly packed pages: engine, power train equipment, undercarriage, control devices, hydraulic cylinder, work implement, and a full torque specification table.
Guessing on a machine this age gets expensive fast. Set a clutch by feel and you can glaze it in a week; run a worn rubber track past its limit and you buy a derailment in soft ground. The manual gives the wear limits, clearances, adjustment values and tightening torques that separate a repair from a repeat teardown.
It is a 1.64 MB PDF with 35 bookmarks, so it opens on a phone in the shed and prints page by page for the bench. Wherever the C20R is parked, the numbers travel with it.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| 1-34 | Engine, Power Train Equipment, Undercarriage, Control Devices, Hydraulic Cylinder, Work Implement, Torque Specifications |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| C20R | ||
| Engine base fixing bolt tightening torque | 4.5~6.0 kgf·m | p. 31 |
| Battery type | 46B24L-MF | p. 8 |
| Battery voltage - 5 hrs rate capacity | 12-36 V-Ah | p. 8 |
| Battery tightening nut (Under) torque | 0.2~0.4 kgf·m | p. 31 |
| Battery tightening nut (Over) torque | 0.8~1.2 kgf·m | p. 31 |
| Starter motor nominal output | 12-1.0 V-kW | p. 8 |
| Starter motor engagement | Magnetic shift | p. 8 |
| FO filter type | Paper type element | p. 7 |
| Hydraulic oil type (also used as transmission oil) | Yanmar super royal oil SAE 10W-30 Diesel engine oil SAE 10W-30 API CD class | p. 14 |
| Idler Fixing Nut Tightening Torque | 35.0~45.0 kgf·m | p. 31 |
| 3TNA72L series | ||
| Intake Valve Clearance (Cold eng.) | 0.15~0.25 mm | p. 21 |
