Part of the Yanmar Parts Manuals.
The crank is out, the machine shop has measured the journals, and the next question is whether Yanmar lists an undersize bearing for this block. This catalog answers it. Publication Y00B4102 covers the 3TNA72L-UBA and 3TNA72L-UBA/B three-cylinder diesels, whether the engine is still bolted into whatever it powers or stripped bare on a stand.
Its 34 pages step through sixteen exploded figures with numbered parts lists: cylinder block, gear housing, flywheel housing and oil sump, cylinder head and bonnet, camshaft, crankshaft and pistons, the lubrication oil and cooling water systems, fuel injection device, fuel pipe, governor, starting motor, generator, and an optional tool and gasket set.
Every callout ties a part on the diagram to its Yanmar part number, including rebuild sizes such as 0.25 and 0.5 oversize pistons, so the order you place matches the engine you measured. The PDF downloads immediately after purchase and prints cleanly for the bench.
Other edition of this manual
What's Inside This Parts Manual
| System | Pages | Key Topics |
|---|---|---|
| Engine | 1-2 | Cylinder Block Assy, Main Bearing, Thrust Bearing, Camshaft Bush, Cylinder Head Gasket, Gasket, Joint PT1 |
| Cylinder Block | 3-4 | Gear Housing Assy, Housing Cover Assy, Oil Seal HTC456208, Knock Pipe, Cover, Pump Cover Gasket, Gasket, Lub. Oil Supply Cap |
| Gear Housing | 5-6 | Lub. Oil Sump Assy, Oil Sump Spacer, Oil Seal Case Assy, Oil Seal, Flywheel Housing, Flywheel Cover Cap |
| Flywheel Housing & Oil Sump | 7-8 | Cylinder Head Assy, Suction Valve, Exhaust Valve, Valve Spring, Spring Retainer, Valve Stem Seal, Valve Cap, Nozzle Protector |
| Cylinder Head & Bonnet | 9-10 | Air Cleaner Support, Support Felt, Air Cleaner, Case, Air Cleaner Element, Dust Pan, Retainer, Air Intake Pipe |
| Suction Manifold & Air Cleaner | 11-12 | Silencer Gasket, Gasket, Silencer, Silencer Stay, Exhaust Manifold, Exhaust Manifold Gasket |
| Exhaust Manifold & Silencer | 13-14 | Camshaft Assy, Camshaft Gear, Thrust Bearing, Push Rod, Tappet, Fuel Cam Bearing, Fuel Injection Pump Cam Assy, Idle Gear Retainer |
| Camshaft & Driving Gear | 15-16 | Crankshaft Assy, Crankshaft Gear, Crankgear, V-pulley, Flywheel Assy, Ring Gear, Piston w/ Rings, Ring Set |
| Crankshaft & Piston | 17-18 | Lub. Oil Pump Assy, Lub. Oil Pump Gasket, Lub. Oil Dipstick, Dipstick Guide, Oil Filter Bracket, Bracket Gasket, Gasket, Lub. Oil Filter |
| Lubrication Oil System | 19-20 | Cooling Water Pump Assy, Cw Pump Assy, Cooling Water Pump Gasket, V-belt, Cooling Water Pump V-pulley, Thermo Switch, Gasket, Thermostat Cover |
| Cooling Water System | 21-22 | Fuel Injection Pump Assy, Plunger w/ Barrel, Retainer, Plunger Spring, Delivery Valve w/ Seat, Delivery Valve Spring, Delivery Valve Holder, Delivery Gasket |
| Fuel Injection Device | 23-24 | F.feed Pump Gasket, Gasket, Feed Pump, Fuel Feed Pump Assy, F.o Strainer Assy, Taper Valve, Taper Valve Spring, Lever |
| Fuel Pipe | 25-26 | Governor Case, Governor Case Gasket, Gasket, Governor Case Cover, Link Color, Link, Governor Weight Assy, Governor Sleeve |
| Governor | 27-28 | Starter 12V- .0W, Retainer, Yoke Assy, Armature Assy, Bearing, Starter Clutch, Starter Pinion, Shaft |
| Starting Motor | 29-30 | Generator, Collar, Plate Assy, Stator, Coupler, Flywheel Assy, Belt Adjuster |
| Generator | 31-32 | Flex Horn, Gasket Set, Cylinder Head Gasket, Bonnet Gasket, Int.manifold Gasket, Silencer Gasket, Exhaust Manifold Gasket, Cooling Water Pump Gasket |
| Tool & Gasket Set Optional | 33-34 | Overview, Parts List, Brush, Gasket, Liquid, Cylinder Head, Rocker Cover, Oil Pan |
Every system also includes overview.
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Main Bearing Undersize | 0.25 (unit not specified) | p. 2 |
| Piston W/Ring Oversize | 0.25 (unit not specified) | p. 16 |
| Ring Set Oversize | 0.25 (unit not specified) | p. 16 |
| Bearing Pin Undersize | 0.25 (unit not specified) | p. 16 |
| V-Belt FM Length | 36.5 (unit not specified) | p. 20 |
| Fuel Pipe Diameter x Length | 12mm x 400mm | p. 24 |
| Governor Link Length (No Color) | 88.8 (unit not specified) | p. 26 |
| Governor Link Length (White) | 88.6 (unit not specified) | p. 26 |
| Starter Motor Rating | 12V-1.0W | p. 28 |
