Description

Komatsu FG35, 38, 40, 45-5, FG35Z 1991 Parts Catalog

Ever spent a Saturday afternoon hunting for a gasket set, only to find the aftermarket catalog had the wrong part number for your Komatsu FG35? I’ve hauled more engines than I care to count, and I can tell you that a mishandled parts order costs you time and money. This 1991 Parts Catalog from Komatsu stops that nonsense cold. It’s 87 pages of factory-sourced part numbers, figure references, and interchangeability codes tied directly to the P40 gasoline engine used in the FG35, 38, 40, and 45-5 models plus the FG35Z.

P40 Gasoline Engine Parts Breakdown

This isn’t some slapped-together aftermarket list. The manual opens with a foreword (page 1) explaining that only engine parts are covered — chassis parts live in a separate volume. If you’re pulling the cylinder block on a FG40, you flip to figure 04-1 for the cylinder block and oil pan. Each figure groups the assembly with a clear illustration and a table of part numbers, quantities, and notes. No guesswork, no cross-referencing three different websites. The figure numbering goes from 04-1 all the way through 37-2, plus a kit section (k-1, k-2) and a notes index (ni-1 through ni-7).

Interchangeability Codes: What They Really Mean

Page 4 lists four codes: A (interchangeable), B (not interchangeable), C (new parts can replace old, but not reverse), and D (discontinued). If you see “A” in the Remarks column, that part swaps straight across model years. “D” means you either find NOS or upgrade to the superseding assembly. Pay attention to the engine serial number cutoff (S22909 and up) listed on the cover — parts changed after that point get a different number. I’ve seen guys order a piston ring set for a pre-S22909 engine and wonder why the gap is wrong. That mistake costs a day of labor.

How This 87-Page Catalog Is Organized

The table of contents on page 5 lists every figure group: Cylinder Block & Oil Pan, Front Cover & Oil Filter, Cylinder Head & Rocker Cover, Piston, Connecting Rod, Crankshaft, and so on. Each group number (like 05-1, 06-2, 07-3) corresponds to a specific illustration page. If you need the crankshaft main bearing set for the FG45-5, go to figure 07-3 and read the STD, OS, and US columns. Oversize and undersize parts are clearly marked — no more guessing if that 0.25 mm OS bearing fits your journal. The manual also includes a service kit table (k-1, k-2) for overhaul kits where you order the whole assembly at once.

Ordering Parts: What Komatsu Expects You to Provide

Before you call your dealer, grab the machine serial number, engine serial number, and service meter hours. The foreword demands this information — without it, you’ll get the wrong part, and it’s your fault, not Komatsu’s. The part quantity listed is per machine or per assembly. If a shim shows “AR” (as required), you order what you need, not a fixed number. And that little dot (·) before a part name? It marks a sub-component of the main assembly. Two dots (··) mean sub-sub-assembly. Miss that, and you might order a valve spring when what you really needed was the entire cylinder head assembly.

Related Manuals You Might Need

• KOMATSU Forklift Shop Manual FG50/60/70 Series
• Komatsu BX50 Series Forklift Parts Manual
• FAI 67-80DT Hydraulic Steering Piston Parts List

For a broader understanding of how engines work, see this Wikipedia article on diesel engines — although the P40 is gasoline, the principles of the bottom end still apply. Alternatively, this Wikipedia article on diesel engines covers combustion cycles that parallel many gasoline engine designs.

Can I use this catalog for the FG50/60/70 models?

No. This catalog is specific to the FG35/38/40/45-5 and FG35Z. The cover page explicitly lists those models. For the FG50/60/70 series, you need the separate volume for that spec code (A4GD2). Ordering from this listing for a FG50 will get you the wrong part numbers.

How do I tell if a part from an older engine still fits my FG35Z?

The interchangeability codes in the Remarks column tell you everything. Look for code “C” — that means new parts can replace old ones, but not the reverse. If the code is “B”, the parts are not interchangeable even if they look the same. Also check the engine serial number: this catalog covers S22909 and up. If your engine is below that, you may need the earlier edition. The date of issue (July 30, 1991) marks the parts revision cutoff. Always cross-check the figure group number and the part number before ordering. I’ve had guys call me saying they ordered a head gasket that matched the picture but the bolt holes didn’t line up — they skipped the code check. Don’t be that guy.

When you need the right part number the first time, this 87-page factory document is the only source you should trust. Every figure, every code, every supersession note comes from Komatsu’s engineering department. Stop wasting time on third-party part lists that are wrong more often than they’re right. Access the Factory Manual.