Part of the Yanmar Parts Manuals.
The crank is out, the micrometer says the journals need a regrind, and the next question is whether Yanmar ever cataloged undersize bearings for this engine. This catalog settles it: 0.25 undersize main and crank-pin bearings and a 0.25 oversize ring set are all listed, with the part numbers to order them.
Publication Y00B3761 is Yanmar's parts catalog for the 3TNA72L-UTB industrial diesel in its YB10-2 specification. Seventy pages in 35 sections run from the cylinder block and gear housing through the fuel injection pump, governor, starting motor, and the gasket set at the back. Every plunger, shim pack, seal, and bush has its listing, so the parts order that comes back matches the engine on your stand.
It does not matter what this engine is bolted into. As a small PDF it goes wherever the work is: on a phone at the bench, or printed and clipped up above the parts washer.
What's Inside This Parts Manual
| System | Pages | Key Topics |
|---|---|---|
| Engine | 1 | |
| Cylinder Block | 2-3 | Cylinder Block Assy, Main Bearing, Thrust Bearing, Camshaft Bush, Cylinder Head Gasket, Joint PT1, Gasket |
| Gear Housing | 4-5 | Gear Housing Assy, Gear Housing Cover, Oil Seal HTC456208, Knock Pipe, Generator Bracket |
| Gear Housing Blind Cover | 6-7 | Cover, Pump Cover Gasket, Lub. Oil Supply Cap, Hydraulic Oil Pump Cover, Blind Cover, F.feed Pump Gasket |
| Flywheel Housing | 8-9 | Flywheel Cover Cap, Bolt, Pin |
| Oil Seal Housing | 10-11 | Oil Seal, Pin, Bolt |
| Lub. Oil Sump | 12-13 | Lub. Oil Sump Assy, Oil Sump Spacer, Plug, O-Ring |
| Cylinder Head | 14-15 | Cylinder Head Assy, Suction Valve, Exhaust Valve, Valve Spring, Spring Retainer, Valve Stem Seal, Valve Cap, Nozzle Protector |
| Rocker Arm | 16-17 | Arm Support Assy, Rocker Shaft Assy, Rocker Arm Assy, Rocker Arm Support, Spring |
| Bonnet | 18-19 | Lub. Oil Supply Cap, Knob, Head Bonnet Assy, Joint, Shelter Plate, Plate Gasket, Bonnet Gasket, Pipe 12X |
| Air Cleaner | 20-21 | Case Assy, Dust Pan Assy, Retainer, Air Cleaner Element, Air Intake Pipe, Suction Pipe, Air Cleaner Support |
| Suction Manifold | 22-23 | Air Intake Manifold, Int.manifold Gasket, Bolt |
| Exhaust Manifold | 24-25 | Exhaust Manifold Gasket, Washer, Bolt |
| Camshaft | 26-27 | Bearing, Fuel Injection Pump Camshaft, Camshaft Gear, Tappet, Push Rod, Fuel Injection Pump Gear |
| Crankshaft | 28-29 | Crankshaft Assy, Crankshaft Gear, V-pulley, Key |
| Flywheel | 30-31 | Flywheel Assy, Ring Gear, Bolt, Pin |
| Piston | 32-33 | Piston w/ Rings, Ring Set, Pin, Circlip |
| Connecting Rod | 34-35 | Connecting Rod Assy, Crank-pin Bearing, Piston Pin Bush, Bolt |
| Driving Gear | 36-37 | Idle Gear Retainer, Idle Gear Shaft, Idle Gear w/ Bush, Idle Gear Bush |
| Lub. Oil Pump | 38-39 | Pump Assy, Lub. Oil, Gasket, L.O.PUMP, Bolt M 6X 20 |
| Lub. Oil System | 40-41 | Lub. Oil Dipstick, Dipstick Guide, Oil Filter Bracket, Bracket Gasket, Lub. Oil Filter, Oil Press Valve Assy, Lub. Oil Pipe Assy, Oil Pressure Switch |
| Cooling Water Pump | 42-43 | Cooling Water Pump Assy, Cooling Water Pump Gasket, V-belt, Cooling Water Pump V-pulley, V-pulley, Cooling Fan, Sub Reservoir Assy, Reservoir Tank Cap |
| Thermostat | 44-45 | Gasket, Thermometer, Thermostat Cover, Thermo.cover Gasket |
| Fuel Injection Pump | 46-47 | Fuel Injection Pump Assy, Plunger w/ Barrel, Retainer, Plunger Spring, Delivery Valve w/ Seat, Delivery Valve Spring, Delivery Valve Holder, Delivery Gasket |
| Fuel Injection Valve | 48-49 | Fuel Injection Valve Assy, Nozzle Assy.fuel Injection, Valve w/ Case Holder, Valve Spring, Seat Spring, Valve Stop Spacer |
| Fuel Strainer | 50-51 | Fuel Strainer Assy, Strainer Body Assy, Taper Valve Spring, Cock Handle, Taper Valve, Spring, Fuel Element, Retaining Ring |
| Fuel Injection Line | 52-53 | Injection Pipe Retainer, Fuel Inject Pipe, Bolt |
| Fuel Line | 54-55 | Fuel Oil Pipe, Gasket, Pipe, Feed Pump |
| Fuel Return Line | 56-57 | Fuel Over Pipe Assy, Joint, Fuel Return Pipe, Gasket |
| Governor | 58-59 | Governor Case Gasket, Governor Case Cover, Governor Weight Assy, Governor Sleeve, Governor Case, Link Color, Spacer Assy, Governor Lever Shaft |
| Control System | 60-61 | Torque Spring Assy, Lead, Wire, Nut |
| Starting Motor | 62-63 | Starter 12V- .0W, Retainer, Yoke Assy, Armature Assy, Bearing, Starter Clutch, Starter Pinion, Shaft |
| Generator | 64-65 | Plate Assy, Stator, Coupler, Collar, Pulley, Flywheel Assy, Belt Adjuster |
| Glow Plug | 66-67 | |
| Gasket Set & Special Tool (Op) | 68-70 | Gasket Set, Cylinder Head Gasket, Pump Cover Gasket, F.feed Pump Gasket, Plate Gasket, Bonnet Gasket, Int.manifold Gasket, Silencer Gasket |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Main Bearing Undersize | 0.25 | p. 2 |
| Piston Ring Set Oversize | 0.25 | p. 32 |
| Connecting Rod Bearing Undersize | 0.25 | p. 34 |
| V-Belt Length | 36.5 FM | p. 42 |
| Governor Link Length (No Color) | 88.8 | p. 58 |
| Governor Link Length (White) | 88.6 | p. 58 |
| Governor Link Length (Red) | 89.0 | p. 58 |
