Description

Isuzu 4BG1 Parts Catalog – 72 Pages of OEM Part Numbers

You’re staring at a pile of parts that don’t match the bolt pattern. The gasket you ordered has the wrong hole count. The head bolt lengths are off by 10mm. That’s the kind of mess that costs you a Saturday and a tow bill. The Isuzu 4BG1 Parts Catalog is the document that stops that. 72 pages of OEM part numbers, exploded diagrams, and assembly notes that came straight from the factory. No aftermarket reprint. No “cross-reference” guesswork. Just the numbers that match the engine on your stand.

This catalog covers the cylinder head cover assembly, cylinder head assembly, and cylinder block assembly. Each section uses a numbered diagram keyed to a parts list. For example, on page 2 you’ll find the cylinder head cover assembly with part numbers for the cover (8971334460), cap (8941332075), oil filler gasket (8941236231), and three head cover gaskets (9111790300). There’s even a supersession note: the head-to-cover gasket (8943109120) replaces the earlier 8944625590. That kind of detail keeps you from ordering a part that’s been discontinued.

Cylinder Head Assembly: Bolts, Seals, and Studs

Page 4 shows the cylinder head assembly in full. The main cylinder head (8971418211) comes as an assembly that includes the items marked with an asterisk. The head bolt list is critical: four M12x115 bolts and four M12x102 bolts. Mix them up and you’ll strip threads or bottom out. Aftermarket catalogs often list a single bolt length—this catalog gives you the exact split. Also listed: valve guides (5117510010), inlet and exhaust valve seat inserts (8970376860 and 5117110280), and a whole set of sealing cups with different OD sizes (45mm, 32mm, 25mm, 20mm, 12.3mm). If you’ve ever had a coolant leak from a misidentified cup plug, you know why this matters.

3 Sections That Save You Time

The catalog is divided into three major assemblies. First is the cylinder head cover assembly (pages 1-2). Second is the cylinder head assembly with the valve train and injector nozzle studs (pages 3-4). Third is the cylinder block assembly (page 5). Each section has its own exploded view and parts list. You don’t flip through generic “engine section” pages—you go straight to the area you need. The block assembly includes the front and rear engine hangers, main bearing studs, and ventilation components. For a 72-page catalog, it packs a lot of specific, hard-to-find part numbers.

Does This Catalog Cover the Entire Engine?

Yes, but only the parts that are exploded in the diagrams. It covers the cylinder head, head cover, block, crankshaft (referenced but not detailed), and camshaft (referenced). It does not include the fuel injection pump, alternator, or starter. Those are separate manuals. If you need the full engine rebuild spec, pair this with the Isuzu Diesel Engine 4BG1 Instruction Manual. The parts catalog alone will get you the right gaskets, bolts, and seals, but you’ll want the repair manual for torque values and clearances.

Why OEM Part Numbers Matter for the 4BG1

Aftermarket parts catalogs are notorious for grouping multiple lengths under one “fits-all” bolt. On the 4BG1, that’s a recipe for a pulled thread or a head gasket that won’t seal. This catalog gives you the exact Isuzu part number—no approximation. It also shows supersessions, like the gasket on page 2 that replaces an older number. If you’re ordering from a dealer or a parts supplier, that original number is what they need. For an overview of how OEM documentation fits into the Automotive Industry Overview, remember that this catalog is the real deal. It’s not a scan of a scan; it’s a direct copy of the original factory document.

No aftermarket substitute.

Audience Fit: Who Needs This Catalog

If you’re pulling a 4BG1 head off a forklift, generator, or excavator, you need this. DIYers who hate returning parts will appreciate the exact part numbers. Professional mechanics will use it to quote jobs accurately and avoid ordering the wrong studs. The catalog is also useful for identifying parts from a motor that’s already apart—just match the diagram to the hardware on your bench. If you’re restoring an old Isuzu diesel, the 72 pages will save you the headache of buying a “universal” head gasket that doesn’t fit.

For related manuals, check out the Isuzu 4BG1 2004 Parts Catalog (same engine, later year) and the Isuzu ZX240-3 Series Parts Catalog – 370 Pages OEM for the complete machine. Need a battery cross-reference? See Automotive Battery for general specs, but for the engine itself, stick with this catalog.

Does this catalog include torque specifications?

No. This is a parts catalog, not a repair manual. It lists part numbers and assembly components. For torque values, get the factory service manual.

What is the difference between this OEM catalog and generic aftermarket parts lists?

Generic aftermarket catalogs often combine multiple bolt lengths into one part number, omit supersession notes, and reuse diagrams that are not accurate for the specific engine variant. This OEM catalog is a direct reproduction of the Isuzu factory document. Each part number is verified against the original engineering prints. The diagrams are exactly as Isuzu published them, so the gasket shape, bolt location, and sealing cup sizes match the real engine. When you order a part using this catalog, you get the piece that was designed for the 4BG1, not a “will fit” substitute.

Stop guessing parts. Access the Factory Manual now and get the right numbers the first time.