Description

Yanmar TB135, 4JH Parts Catalog – OEM Factory Exploded Diagrams & Part Numbers

You’ve got a Yanmar TB135, 4JH engine on the bench or in the machine, and you need a part. Maybe it’s a fuel injection pump or a camshaft gear. You pull up some aftermarket parts list and half the numbers don’t match. Then you spend an hour on the phone with the dealer, or worse, order the wrong part and wait another week. That’s the kind of time-waste I’ve seen cost shops real money. This is a factory Parts Catalog – 46 pages of exploded diagrams, OEM part numbers, and the exact breakdown Yanmar uses. No cross-referencing, no guessing. If you’re working on a TB135 with a 3TNV88-QT8 or a 4JH engine, this is the only document you need to pull the right part the first time.

Let me tell you what’s inside. This catalog covers the engine families for the TB135 tractor – both the 4JH and the 4JH-DT, 4JH-ST variants. The table of contents reads like a who’s who of engine assemblies: Cylinder block, Camshaft & driving gear, Crankshaft & piston, Cooling water system, Fuel injection pump, and Valve train components. Each section is a full-page exploded view with item numbers, part numbers, descriptions, and quantities. You don’t have to translate Japanese – the part numbers are universal, and the illustrations are clear enough that even a beginner can point to the broken piece and order the correct replacement. For example, the fuel injection pump section (Fig. 10 and Fig. 11) shows the pump assembly, inner parts, governor, and injection valve, with specific part numbers like 725995-51950 for the 4JH-DT pump. I’ve seen guys order the wrong pump because they didn’t have this level of detail – that mistake costs hundreds.

What This 46-Page Parts Catalog Covers

This is not a service manual. It’s a parts reference – the same one Yanmar dealers use. The 46 pages cover every major assembly: Fig. 1 Gear Housing, Fig. 2 Flywheel Housing & Oil Sump, Fig. 3 Cylinder Head & Bonnet, Fig. 4 Suction Manifold & Air Cleaner, Fig. 5 Exhaust Manifold & Silencer, Fig. 6 Camshaft & Driving Gear, Fig. 7 Crankshaft & Piston, Fig. 8 Lube Oil System, Fig. 9 Cooling Water System, Fig. 10 Fuel Injection Pump, Fig. 11 Fuel Injection Pump (Inner Parts) with sub-sections for Governor and Fuel Injection Valve, Fig. 12 Fuel Line, Fig. 13 & 14 Starting Motor (split by production date), Fig. 14-1 Generator, Fig. 15 Gasket Set, and Fig. 16 (not specified). Every page has a parts list table with REF NO., PARTS NO., Description, Qty, and Remarks. The Remarks column notes special fits like compensator type or optional parts. For example, on the fuel injection pump page, you’ll see notations like “(A)-4JH-DT” and “(B)-4JH-ST” to identify which pump matches which engine variant. That level of specificity is what keeps you from ordering the wrong item.

3 Engine Systems You Can Identify with This Manual

First, the cylinder block assembly – Fig. 0 (Cylinder Block) shows the block, liners, and all internal components. Second, the camshaft and driving gear (Fig. 6) – critical for timing and valve operation. Third, the crankshaft and piston assembly (Fig. 7) – understand the rotating assembly parts. The manual also covers the cooling water system (Fig. 9) – water pump, thermostat, hoses – and the fuel system from injection pump to lines (Fig. 10-12). And of course, the valve train parts are in the cylinder head section (Fig. 3) and camshaft section. If you’re rebuilding a 4JH or just replacing a worn injector, you need the correct part number for each of these systems. Generic parts catalogs mix up the 4JH-DT and 4JH-ST variants – this manual separates them by engine code.

Using the Exploded Diagrams for Correct Part Numbers

Open the manual to any figure. You’ll see an illustration with numbered callouts. Next to the illustration is a table. Find the callout number, read across to the parts number column. That’s your OEM part number. For example, on the fuel injection pump page (Fig. 29 in the OCR), item 1 is the pump itself – part number 725995-51950 for 4JH-DT or 725995-51951 for 4JH-ST. The table also lists the screw (M6 x 16), nut, gasket, and roller bearing. The Remarks column tells you if the part is optional or fits certain serial number ranges. If you’re ordering parts for a TB135 with a 4JH engine, cross-reference the engine serial number (starting from 13514051) to the applicable variant. This manual saves you the trip to the dealer parts counter – you can order directly from the number.

Why OEM Documentation Beats Aftermarket Parts Lists

Aftermarket parts catalogs renumber or aggregate parts across multiple engine families. They might list a “fuel injection pump” without specifying whether it’s for the 4JH-DT or 4JH-ST. That’s how you end up with the wrong pump, wrong gasket, or wrong fuel line. This is a Yanmar factory publication – scanned from the original print. The part numbers are the ones etched on the components. You can verify them against the physical part. The diagrams are drawn to scale, showing the exact orientation of bolts, seals, and brackets. I’ve been burned by aftermarket manuals that omitted the compensator type for the injection pump – that’s a costly mistake. Stick with the OEM source. For related Yanmar engine parts catalogs, check out Yanmar 4JH Parts Catalog – 132 Page Factory Specs for a more extensive version, or Yanmar 4JH-DT, 4JH-DTY, TB135, 4JH-DTZ 1997 Parts Catalog for a specific year. Also available: Ammann Yanmar B12 B17 1991 Parts Catalog – OEM Factory Specs. For background on the automotive industry standards, see Automotive Industry Overview and Automotive Industry Overview.

Is This Manual Right for Your TB135 or 4JH Engine?

If you own a Yanmar TB135 compact tractor or any equipment powered by a 4JH diesel engine (4JH-DT, 4JH-ST, 4JH-DTZ, 4JH-SZ7), this catalog is for you. It covers the engine as installed in the TB135 with cab (3TNV88-QT8) or canopy (QTB1) from serial number 13514051 onward. The manual is in English and Japanese, but the part numbers and diagrams are language-independent. Beginners can use it – just match the picture to the part. Professionals will appreciate the rapid identification of sub-assemblies. The 46 pages contain all the part numbers for a full engine rebuild. It does not contain service procedures, torque specs, or repair instructions – that’s a separate service manual. But for ordering parts, this is the final word.

Frequently Asked Questions

Does this catalog include service procedures like torque values or repair steps?

No. This is a parts catalog only. It lists part numbers, exploded diagrams, and quantities. You need a separate Yanmar service manual for torque specs, timing, and assembly procedures.

What engine models are covered?

The catalog covers 4JH-DT, 4JH-ST, 4JH-DTZ, and 4JH-SZ7 variants as used in the Yanmar TB135. It also includes the 3TNV88-QT8 engine for cab models. The fuel injection pump section distinguishes between DT and ST versions.

Can I use this catalog for other Yanmar engines like the 3TNV or 4TNV?

Only if the engine is the same series (4JH or 3TNV88) and installed in a TB135. Parts for other models may differ. Check the part number against the physical component before ordering.

How do I read the part number references in the tables?

Each table has columns: REF NO. (callout number on diagram), PARTS NO. (OEM number), DESCRIPTION, QTY, and Remarks. The Remarks column may indicate the engine variant (e.g., A-4JH-DT) or optional parts. The part numbers like 725995-51950 are the key to ordering.

So here’s the bottom line: if you’re tired of guessing which parts go in your Yanmar TB135 or 4JH engine, get this catalog. Open it, find the exploded view, read the part number, and order. That’s the factory way. Access the Factory Manual and start identifying parts correctly.