Description

Yanmar 4JH-DT, 4JH-DT2Y 1997 Parts Catalog

You’ve got a Yanmar 4JH-DT or 4JH-DT2Y on the stand, and the parts book you’re holding is a reprint from some third-party outfit that swapped the part numbers. I’ve seen that happen. A guy orders a fuel injection pump assembly based on an aftermarket listing, gets the wrong unit, and the boat sits another week. That’s wasted time and money. The Yanmar 4JH-DT, 4JH-DT2Y 1997 Parts Catalog from AutoRepairManuals is the original OEM print – 48 pages of factory part numbers, explosion diagrams, revision notes, and supersession data. Nothing else gives you that.

For context: I’ve been turning wrenches for 28 years, and I’ve seen more parts counters than I’ve had hot dinners. When you’re ordering a part for a 4JH-DT that’s got a boost compensator (Fig. 29 in this catalog), you need the exact reference number. The aftermarket catalogs might show a generic pump, but they miss the engine-specific variants like the 4JH-DT2Y with the “E” prefix. This OEM catalog lists both – (A) for 4JH-DT, (E) for 4JH-DT2Y – and includes the critical remarks about which serial numbers apply. That’s the difference between a part that fits and one that doesn’t.

What This Parts Catalog Actually Covers

The catalog is organized by engine system, with exploded views and a parts list for each. The OCR excerpt shows the fuel injection pump section (Fig. 29) for the 4JH-DT and 4JH-DT2Y, including boost compensator variants. Other sections likely cover the cylinder head, block, cooling system, and electrical components – though the table of contents is not provided in the excerpt. Every page uses the same format: a reference number, the OEM part number, a description (often in Japanese and English), quantity, and remarks. For example, the fuel injection pump entry lists parts like “759665-51390” and “759665-51391” with notes about engine serial numbers. That kind of detail is what you need to avoid ordering a screw that’s the wrong thread pitch.

OEM Part Numbers vs. Aftermarket: Why It Matters

I’ve seen aftermarket parts catalogs that list a “fuel injection pump” for the 4JH-DT but omit the boost compensator option. The factory catalog distinguishes between engines with and without boost compensator, and even specifies which reference numbers apply to which serial range (E/#00155 and earlier). If you order a generic pump, you might get the wrong delivery valve or governor assembly. The OEM catalog also includes the original Japanese notations – useful if you’re cross-referencing with a Yanmar dealer who speaks the language. For a Automotive Industry Overview context, the precision of OEM documentation is the foundation of any reliable repair or rebuild. This is a 1997 print, so it matches the exact production run of these engines.

Who Needs This 48-Page Catalog

If you’re a DIY mechanic working on a boat or a marine diesel generator with a 4JH-DT or 4JH-DT2Y, this is the missing piece. You’ve got the engine, you’ve got the tools, but you don’t have the part numbers. Local parts houses might give you a cross-reference that’s close but not exact. This catalog gives you the exact OEM number, so you can order from any Yanmar dealer or online source with confidence. It’s also valuable for a shop owner who needs to verify parts for a customer’s engine without pulling the unit apart first. The 48 pages are compact – fits in a toolbox drawer or a binder next to the Yanmar 4JH-DT Series Engine Parts Catalog 1997.

How to Read the Exploded Views and Reference Numbers

Each figure (like Fig. 29) shows a component group with a reference number for each part. The parts list below the figure gives the Part No., Description, QTY, and Remarks. The Remarks column is where you’ll find notes like “(A) 4JH-DT, (E) 4JH-DT2Y” and serial number ranges. Pay attention to the “Ref. No.” column – it matches the numbers on the diagram. If you need a screw, you look up the reference number, find the part number, and order that. The catalog also includes a section on how to read the part numbering system (page 1 of the original). This is basic stuff, but skipping it leads to mistakes. I’ve seen guys order a “SCREW W 16” (part number 260002-06012) when they needed the longer variant (260022-06002). The catalog shows both.

3 Systems You Can Source Parts For

Based on the OCR excerpt, the catalog covers at least the fuel injection system (Fig. 29). Given that it’s a full parts catalog for the 4JH-DT/4JH-DT2Y, expect sections for:

• Engine block and cylinder head assembly
• Fuel system (injection pump, injectors, lines)
• Cooling system (heat exchanger, raw water pump)

These are the high-failure areas on marine diesels. Having the OEM part numbers for gaskets, seals, and pumps means you can order the right parts before you even pull the unit apart. No waiting for a second shipment because the first part was wrong.

Yanmar TL150 4JH Series Engine Parts Catalog and Yanmar 4JH-DT 4JH-DTZ 1997 Parts Catalog are also available if you need cross-references for related models.

FAQ – Yanmar 4JH-DT/4JH-DT2Y Parts Catalog

Is this the same as a service manual?

No. This is a parts catalog – it lists part numbers and exploded views, not repair procedures. You need the service manual for torque specs and step-by-step repairs.

Does this catalog cover the 4JH-DT2Y engine with the “E” prefix?

Yes. The OCR excerpt shows the fuel injection pump section lists both (A) for 4JH-DT and (E) for 4JH-DT2Y. The remarks column includes serial number ranges for each variant, so you can identify which parts apply to your engine. For example, the boost compensator type is standard on both models from serial number E/#00156 onward, but earlier engines may have a special order specification. The catalog includes these notes. Without this, you might order a pump that’s missing the compensator port or has the wrong delivery valve. I’ve seen it happen – a guy with a 4JH-DT2Y serial number E/#00145 got sent a pump for the later series, and the mounting holes didn’t line up. This catalog would have prevented that.

If you’re tired of playing the parts-ordering lottery, get the real thing. Access the Factory Manual from AutoRepairManuals – the 48-page OEM Yanmar parts catalog for 4JH-DT and 4JH-DT2Y engines. No aftermarket fluff, no reprints – just factory part numbers and exploded views.