Part of the Yanmar Parts Manuals.
Strip a 3TNC80L-RB to a bare block and every collar, washer, and O-ring has to go back exactly where Yanmar put it, with the right replacement on order before the head goes back on. This Yanmar parts catalog, publication Y00B4461-1, is what makes that possible: 35 pages of exploded views and numbered parts lists for the complete engine.
Coverage runs from the cylinder block, gear housing, and flywheel housing through the camshaft, crankshaft and pistons, cylinder head, fuel injection pump and pipes, governor, lube oil and cooling water systems, starting motor, and generator. It also flags previous-model parts and repair parts where the factory lists them. Whether the engine sits in a tractor, a genset, or on a stand in your shop, the part numbers are the same.
The bookmarked PDF is small enough to carry on a phone to the parts counter, so the rebuild does not stall waiting on a second shipment because the first number was a guess.
What's Inside This Yanmar 3TNC80L-RB, Y00B4461 Parts Manual
| System | Pages | Key Topics |
|---|---|---|
| Engine | 1 | Small Vertical (B), Tnc |
| Cylinder Block | 2-3 | Cylinder Block Assy, Main Bearing, Thrust Bearing, Camshaft Bush, Head Gasket |
| Gear Housing | 4-5 | Gear Housing Assy, Oil Seal, Lub. Oil Supply Cap, Gears Housing Flange, Hydraulic Oil Pump Cover, Gasket, Knock Pipe, Blind Cover |
| Flywheel Housing & L.O Sump | 6-7 | Flywheel Housing, Flywheel Cover Cap, Lub. Oil Sump Spacer, Oil Sump Assy, Oil Seal Case Assy, Oil Seal |
| Cylinder Head & Bonnet | 8-9 | Cylinder Head Assy, Suction Valve, Exhaust Valve, Valve Spring, Spring Retainer, Valve Stem Seal, Valve Cap, Rocker Support Assy |
| Suc/Exh Manifold | 10-11 | Suction Manifold, Gasket, Exhaust Manifold, Exhaust Manifold Gasket, Air Heater |
| Camshaft & Driving Gear | 12-13 | Camshaft Assy, Thrust Bearing, Camshaft Gear, Idle Gear Shaft, Gear W/ Bush, Idle Gear Bush, Tappet, Push Rod |
| Crankshaft & Piston | 14-15 | Crankshaft Assy, Crankshaft Gear, Crankshaft V-Pulley, Flywheel W/ Gear, Ring Gear, Piston W/ Rings, Ring Set, Connecting Rod Assy |
| Lub. Oil System | 16-17 | Lub. Oil Pump Assy, Lub. Oil Pump Gasket, Lub. Oil Dipstic, Dipstick Guide, Gasket, Oil Inlet Pipe Assy, Strainer Bracket, Filter 90X80L |
| Cooling Water System | 18-19 | Cooling Water Pump, Cooling Water Pump Gasket, V-Belt, V-Pulley, Cooling Fan, Spacer, Thermostat Cover, Gasket |
| Fuel Injection Pump | 20-22 | Camshaft, Thrust Ball Bearing, Cam Shaft Support, Plunger W/ Barrel, Retainer a, Plunger Spring Shoe, Plunger Spring |
| Fuel Injection Pipe | 23-24 | Fuel Injection Valve Assy, Fuel Injection Nozzle Assy, Nozzle Holder Assy, Nozzle Spring, Nozzle Spring Seat, Stop Plate, Injection Pipe Retainer |
| Fuel Pipe | 25-26 | Fuel Strainer Assy, Taper Valve, Taper Valve Spring, Lever, Strainer Cup, Retaining Ring, Spring, Element |
| Governor | 27-28 | Governor Case, Governor Case Gasket, Governor Case Cover, Case Cover Gasket, Link, Governor Weight Assy, Sleeve, Control Shaft Assy |
| Starting Motor | 29-30 | Starter, Armature Assy, Bearing, Field Coil Assy, Brush, Rear Cover, Brush Holder Assy, Brush Spring |
| Generator | 31-32 | Collar, Plate Assy, Stator, Coupler, Flywheel Assy, Adjuster |
| Gasket Set (Optional) & Tool | 33-35 | Gasket Set, Head Gasket, Bonnet Gasket, Exhaust Manifold Gasket, Lub. Oil Pump Gasket, Cooling Water Pump Gasket, Flex Horn, Liquid Gasket |
Every system also includes an exploded view and a parts list.
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Parallel Pin Size | 8x16 mm | p. 6 |
| Plug/Drain Plug Thread Size | M22 | p. 6 |
| Pipe Plug Thread Size | PT1/4 | p. 8 |
| Nut Thread Size & Pitch | M8xP1.0 | p. 8 |
Yanmar 3TNC80L-RB, Y00B4461 Common Problems This Manual Covers
Hard starting from air in the fuel
A small diesel that cranks forever after sitting usually has air sneaking in through a tired strainer, pipe joint, or check valve. The Fuel Pipe section breaks out the fuel strainer assembly, pipes, and check valve so you can replace the leaking piece instead of the whole run.
Manual Section: Fuel Pipe p. 25Cranks but starves for fuel
When the engine spins but will not fire, worn injection pump internals are a common culprit on high-hour engines. The Fuel Injection Pump section lists the pump assembly along with the plunger with barrel, tappet assembly, and control rack, with classified marks noted so you match the correct variant.
Manual Section: Fuel Injection Pump p. 20Smoke and rough running under load
Poor spray from a tired nozzle shows up as smoke and uneven running long before it shows up as a no-start. The Fuel Injection Pipe section covers the injection nozzle assemblies, retainers, and pipes you will be ordering after a pop test sends one to the bench.
Manual Section: Fuel Injection Pipe p. 23Overheating and coolant loss
A stuck thermostat or a weeping water pump will cook a small diesel quickly. The Cooling Water System section lays out the cooling water pump, thermostat cover, and cooling fan as separate assemblies so you can order exactly the piece that failed.
Manual Section: Cooling Water System p. 18Low oil pressure warning
Falling oil pressure on the gauge means checking the pump and relief valve before blaming the bearings. The Lub. Oil System section itemizes the lube oil pump assembly, oil pressure valve assembly, and dipstick, including previous-model parts.
Manual Section: Lub. Oil System p. 16Starter drags or fails to engage
A starter that clicks, drags, or spins without engaging is a wear item, not a mystery. The Starting Motor section breaks the starter into its armature assembly and clutch assembly so you can rebuild it rather than paying for a complete unit.
Manual Section: Starting Motor p. 29Surging or hunting at idle
An engine that hunts at idle often has worn governor springs or a sticking fuel control lever. The Governor section shows the case, fuel control lever assembly, and springs in exploded view so you can see what has stretched or come adrift.
Manual Section: Governor p. 27Frequently Asked Questions
Which engine does this parts catalog cover?
It covers the Yanmar 3TNC80L-RB, part of Yanmar's small vertical TNC series, under publication number Y00B4461-1. Where a component changed during production, the catalog flags previous-model parts, for example in the Cylinder Head & Bonnet and Lub. Oil System sections, so earlier builds can still be matched.
Does it include torque specs or rebuild procedures?
No. This is a parts catalog: exploded views and numbered parts lists for identifying and ordering components, from the crankshaft and piston assemblies down to individual O-rings. For valve lash, clearances, and torque sequences you need the service manual; this book tells you exactly what to order once you have measured.
Are fuel injection pump internals listed individually?
Yes. The Fuel Injection Pump section lists the pump assembly plus its internals, including the plunger with barrel, tappet assembly, and control rack, with classified marks noted where parts differ between pumps. The nozzles, retainers, and injection lines follow in the Fuel Injection Pipe section. p. 20
Is there a gasket set for a full reseal?
The Gasket Set (Optional) & Tool section lists the optional gasket set along with liquid gasket, so you can order sealing parts as a set for a top-end or full reseal instead of chasing individual gaskets through each assembly page. p. 33
How quickly can I access this manual after buying?
Immediate download of the complete 35-page searchable Parts Catalog. Access it on any device, from a laptop at your desk to a phone in the field.
Is this manual print-friendly?
The PDF is DRM-free. Print whatever sections you need to take out to the shop. Standard letter or A4 paper works.
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