Description

Mitsubishi S4Q2-61SD, S4Q2-Y162SD, S4Q2-Y262SD, S4Q2-Y362SD, S4Q2-Z261SD 2009 Parts Catalog

I have seen more engines torn down because someone ordered the wrong piston ring set than I care to count. If you are working on one of these Mitsubishi S4Q2 diesel engines—the S4Q2-61SD, S4Q2-Y162SD, S4Q2-Y262SD, S4Q2-Y362SD, or S4Q2-Z261SD—you need the factory parts catalog. Not a reprint, not a generic aftermarket PDF. The original OEM document. This 140 pages catalog from 2009 is the only way to guarantee you are ordering the correct Mitsubishi genuine part for these engines built for SDMO. Page 1 shows the document number 98615-D4050 and the date. Page 3 gives you the exact engine serial number ranges: S4Q2-61SD starts at 010194-UP, Y162SD at 016425-UP, Y262SD at 028184-UP, Y362SD at 070422-UP, Z261SD at 049757-UP. If your engine serial falls outside those ranges, this catalog does not apply. That is the kind of precision you get from factory documentation.

Engine Assembly Breakdown

Each section in this catalog follows the standard Mitsubishi layout: exploded-view diagrams with callout numbers, then a table with part number, description, quantity per engine. You get the cylinder head, block, timing gears, pistons, connecting rods, and crankshaft. The fuel injection pump and governor assembly are listed separately. This is not a service manual—you will not find torque specs or repair procedures here. What you do get is the exact part number for every bolt, gasket, seal, and bracket that Mitsubishi designed for these engines. If you need the service manual for the S4Q2 series, look for the separate shop manual. This is strictly for ordering parts.

What Part Numbers Are Included?

Every genuine Mitsubishi part for the S4Q2-61SD, S4Q2-Y162SD, S4Q2-Y262SD, S4Q2-Y362SD, and S4Q2-Z261SD. The catalog covers the water pump, oil cooler, thermostat housing, alternator bracket, starter motor, and all the small hardware that aftermarket catalogs often skip. You will find the OEM part number for the cylinder head gasket, the valve guides, the injector nozzles, and the fuel lines. Page 1 also includes a note that “MITSUBISHI GENUINE PARTS” are produced under strict quality control and have passed rigorous inspections. That is not marketing fluff—that is a direct warning against using imitation parts. I have seen aftermarket piston rings fail in under 500 hours on a generator set. Do not risk it.

3 Reasons to Use Only OEM Parts

First, the metallurgy. Mitsubishi engines use specific alloys for pistons and rings that aftermarket suppliers do not replicate exactly. Second, the tolerances. Factory parts are machined to the same specs as the original assembly. Third, the liability. If you install a counterfeit part and the engine grenades, your warranty is void. This catalog lists the genuine parts—nothing else. For related models, check the Mitsubishi S3L2 2009 Parts Catalog – OEM Factory Specs or the Mitsubishi S6A3-PTA PTK 1991 Parts Catalog – Factory OEM Specs. For larger diesel engines, the Mitsubishi 4DQ50 Parts Catalog – OEM Diesel Engine Specs is also available on this site.

Verify Your Serial Number Before Ordering

Look at the data plate on your engine. It should have a model number and a serial number. Cross-check that serial against the ranges listed on page 3 of this catalog. For example, the S4Q2-Z261SD only applies to engines with serial number 049757 and up. If your engine is 049756, this catalog will not be accurate. That is the kind of detail you get from an OEM document—no guessing. I have had customers tell me they ordered a head gasket from a generic listing and it did not fit. The gasket was for an earlier production run. With this catalog, you see the exact part number for your production range. That saves you the restocking fee and the wait for the right part.

Fuel System Components: Factory Listing

The injection pump, delivery valves, and injector nozzles are all covered. The catalog gives you the part numbers for the complete pump assembly, the plunger and barrel sets, and the nozzle holders. If you are rebuilding an S4Q2 injection pump, you need these numbers to order the correct calibration parts. Aftermarket catalogs often group three different nozzle types under one generic number. This catalog lists the specific nozzle part number for each engine model. That is the difference between a rebuild that lasts and one that leaks oil within a month.

How to Use This Catalog with a Service Manual

If you are doing a full overhaul, you will need both the shop manual and this parts catalog. The shop manual tells you how to disassemble and reassemble. This catalog tells you what part number to order when you find a worn bearing or a cracked housing. They work together. Start by disassembling using the service manual. Make a list of every part you replace. Then look up the numbers in this catalog. Order genuine Mitsubishi parts. Reassemble using the shop manual torque specs and clearances. That process has kept generator sets running in remote oil fields for decades. Do not cut corners. Use factory documentation.

If you are serious about keeping these Mitsubishi S4Q2 engines running, get the original factory parts catalog. The PDF is a direct scan—no reprint, no OCR errors, no missing pages. Every part number is legible. Every diagram is clear. You can zoom in to read the callouts. This is the same document the dealer parts counter uses. Access the Factory Manual now and stop ordering parts by guesswork. For industry context on why aftermarket parts fail, read the Automotive Industry Overview. If you need to test your battery or charging system, refer to Automotive Battery specs separately.

Does this catalog include torque specs?

No. This is a parts catalog, not a service manual. Torque values are in the separate shop manual for the S4Q2 engine.

How do I use the serial number to find parts?

Each engine model has a serial number starting point listed on page 3 of the catalog. For example, S4Q2-61SD: 010194-UP. The catalog groups parts by engine serial number range. You must confirm your engine’s serial number matches the range listed before ordering parts. If your serial is below the starting point, this catalog will not apply. The catalog covers serial numbers from the beginning of production for each model variant.

Can I use this catalog for other Mitsubishi engines?

No, this is specific to the S4Q2-61SD, S4Q2-Y162SD, S4Q2-Y262SD, S4Q2-Y362SD, and S4Q2-Z261SD models. Other S4Q2 variants or engines like the S3L2 have different part numbers.

Is this a reprint?

The PDF we sell is a direct scan of the original 2009 factory document. It is not a reprint or a third-party compilation.