Part of the Yanmar Parts Manuals.
An engine on the stand goes back together only as fast as the parts arrive, and nothing stalls a Yanmar rebuild like guessing at a part number over the phone while the block sits open on the bench. This catalog settles that. It is Yanmar publication Y00B4202, the factory parts catalog for the 4TN84L-RBA diesel: 39 pages of exploded views and part numbers covering the engine from cylinder block to camshaft.
Seven sections walk the engine group by group: Cylinder Block, Gear Housing, Flywheel Housing and Lub. Oil Sump, Cylinder Head and Bonnet, Suction Manifold and Air Cleaner, Exhaust Manifold and Silencer, and Camshaft and Driving Gear. Every gasket, seal, bearing, and bolt is keyed to its diagram so you order once and order right.
It downloads as a PDF the moment you pay, prints clean for the bench, and it is yours to keep for the life of the engine.
What's Inside This Yanmar 4TN84L-RBA Parts Manual
| System | Pages | Key Topics |
|---|---|---|
| Cylinder Block | 3-4 | Gear Housing Assy, Oil Seal, Lub. Oil Supply Cap, Gears Housing Flange, Hydraulic Oil Pump Cover, Hydraulic Oil Pump Gasket, Gasket, Knock Pipe |
| Gear Housing | 5-6 | Flywheel Housing, Flywheel Cover Cap, Lub. Oil Sump Assy, Oil Pan Cover, Oil Sump, Knock Pipe, Oil Seal Case Assy, Oil Seal |
| Flywheel Housing & Lub. Oil Sump | 7-8 | Cylinder Head Assy, Valve Guide, Intake Valve, Exhaust Valve, Valve Spring, Spring Retainer, Valve Stem Seal, Valve Cap |
| Cylinder Head & Bonnet | 9-10 | Hose, Air Cleaner Assy, Case, Dust Pan Assy, Element Retainer, Strainer Element, Brace Assy, Rubber Seat |
| Suc. Manifold & Air Cleaner | 11-12 | Silencer Gasket, Gasket, Silencer, Silencer Stay, Exhaust Manifold, Exhaust Manifold Gasket |
| Exh. Manifold & Silencer | 13-14 | Camshaft Assy, Camshaft Gear, Push Rod, Tappet, Idle Gear Shaft, Gear w/ Bush, Idle Gear Bush |
| Camshaft & Driving Gear | 15-39 | Crankshaft Assy, Crankshaft Gear, Crankshaft V-pulley, Flywheel Assy, Ring Gear, Piston w/ Ring, Piston Ring Set, Ring Set |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Camshaft Key Dimensions | 7 x 14 mm | p. 14 |
| Spring Pin Dimensions (Crankshaft & Piston) | 4.0 x 10 mm | p. 16 |
| Fuel Injection Pump Spring Pin Dimensions | 5 x 10 mm | p. 22 |
Yanmar 4TN84L-RBA Common Problems This Manual Covers
Low oil pressure and worn main bearings
Falling oil pressure on a high-hour 4TN84L-RBA often ends at the main bearings. The Cylinder Block section diagrams the block assembly, bearing caps, and main bearings with their Yanmar part numbers, so you can order the full bottom-end set before the crank comes out.
Manual Section: Cylinder Block p. 3Oil weeping from the gear housing
A slow leak at the front of the engine usually traces to a hardened oil seal or a tired gasket on the gear housing. This section lists the housing assembly, oil seal, and lube oil supply parts so the whole joint gets fresh sealing in one order.
Manual Section: Gear Housing p. 5Oil pan and sump gasket leaks
Drips collecting under the engine after years of heat cycles point to the sump sealing surfaces. The Flywheel Housing and Lub. Oil Sump section identifies the oil pan, sump assembly, covers, and flywheel housing hardware by part number.
Manual Section: Flywheel Housing & Lub. Oil Sump p. 7Hard starting from worn valve stem seals
Smoke at startup and oil creeping down the guides mean the head needs to come off. The Cylinder Head and Bonnet section keys the head assembly, valve guides, valve stem seals, and rocker arm shaft so you can build a complete top-end parts list before disassembly.
Manual Section: Cylinder Head & Bonnet p. 9Black smoke from a starved intake
A clogged air cleaner element chokes the engine and shows up as black smoke and lost power. This section lists the air cleaner assembly, element, dust pan, strainer, and intake manifold parts so a proper service is one order away.
Manual Section: Suc. Manifold & Air Cleaner p. 11Exhaust manifold gasket failure
A ticking exhaust leak that grows with load usually means a blown manifold gasket or corroded silencer hardware. The Exhaust Manifold and Silencer section shows the manifold, silencer, gaskets, and the plated studs that seize and snap on removal.
Manual Section: Exh. Manifold & Silencer p. 13Worn camshaft and noisy valve train
Clatter that valve lash adjustment will not cure points at the cam, pushrods, and idle gear. The Camshaft and Driving Gear section, the largest in the book, diagrams the camshaft assembly, push rods, shafts, and bushed gears with their part numbers.
Manual Section: Camshaft & Driving Gear p. 15Frequently Asked Questions
Is this a service manual or a parts catalog?
It is the factory parts catalog, Yanmar publication Y00B4202. You get exploded diagrams and part numbers for the 4TN84L-RBA, not repair procedures. It is the reference you use to identify and order the correct components during a rebuild.
Which engine does this catalog cover?
The Yanmar 4TN84L-RBA diesel engine only. Wherever the engine is installed, the 39-page catalog covers the engine itself across seven sections, from the Cylinder Block through the Camshaft and Driving Gear group.
Can I find main bearing and bearing cap part numbers?
Yes. The Cylinder Block section diagrams the block assembly with its bearing caps and main bearings, each keyed to a Yanmar part number, along with the plugs, gaskets, and bolts for the bottom end. p. 3
Does it cover the cylinder head and valve parts?
The Cylinder Head and Bonnet section lists the head assembly, valve guides, valve stem seals, and rocker arm shaft components, so you can price out a complete top-end refresh before pulling the head. p. 9
How quickly can I access this manual after buying?
A 39-page Parts Catalog in searchable PDF format, available the moment you complete checkout. View on computer, tablet, or phone, with no shipping wait.
Can I print this manual?
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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