Description

Komatsu FG20, FG30, FG20H, FG20N, FG30N Parts Catalog – Factory Spec Data

Somebody ordered the wrong part again. That’s how a whole afternoon gets burned – waiting on a backordered gasket because the part number on the box didn’t match the engine serial. If you’ve worked on Komatsu FG20, FG30, FG20H, FG20N, FG30N forklifts, you know the feeling. The Parts Catalog is what stops that cycle. It’s not a service manual – there are no torque specs or repair steps – but without it you’re guessing on every single clutch plate, hydraulic seal, and bearing. This is the exact book the Komatsu dealer uses to pull parts. 512 pages, factory-printed diagrams, and serial number splits that actually line up with what’s sitting in your shop.

Flip to page 1 and you see the coverage: FG20/25-16, FG20H/25H-16, FG20N/25N-16, FG30N-16, FG30-16, plus the diesel FD variants. Each model gets a detail code (G1, G1H, G1N, G2N, G2) that ties every illustration to a specific machine. You don’t have to guess which throttle cable fits a 2008 FG20N – the serial number column on each page tells you exactly when Komatsu switched the design. That’s the difference between a parts counter throwing a number at you and actually getting the right piece the first time.

Parts Identification: What You Get with 512 Pages

Every left-hand page is an exploded illustration. Every part on that drawing has an index number, and the facing right-hand page lists the corresponding part number, description, quantity, and applicable serial number range. The format is dead simple: find the figure number, locate your part, read the part number. No guesswork. The catalog includes both standard equipment and optional attachments – if your forklift has a sideshifter or a different mast height, the parts are listed separately with their own detail codes. You will also find assembly-level entries marked with an asterisk, and sub-assembly components marked with dots. That matters when you order a steering cylinder assembly and need the wiper seal inside it.

FG20, FG30, FG20H, FG20N, FG30N – Which Model Do You Have?

Walk up to any of these machines and check the data plate. The model designation – FG20, FG30, FG20H, FG20N, FG30N – determines which parts book section applies. FG20 and FG25 share a detail code (G1), while FG20H gets G1H, FG20N gets G1N, FG30N gets G2N, and FG30 gets G2. If you try to use a G1 diagram for a G2N machine, the part numbers will be wrong. That is why the manual prints the detail code on every figure page. Cross-reference it with your serial number (the book covers units from 700001 and up) and you eliminate the mismatch. One more thing: the diesel FD series uses a completely different group of detail codes (D1, D1H, D1N, D2, D2N) – do not mix them up.

7 Sections of Exploded Diagrams and Part Numbers

The catalog is organized by functional groups: engine, torque converter, transmission, drive axles, steering, brakes, hydraulics, mast, and electrical. Each group contains multiple figures. For example, the engine section includes separate drawings for cylinder head, oil pan, fuel injection pump, and alternator mounting. Every part number is an OEM Komatsu number – no aftermarket cross-references, no “equivalent” substitutions. If you need a piston ring set for a FG30N, the part number listed is what the factory built the engine with. That matters when the aftermarket ring pack is 0.1 mm too thin and you get blow-by after 50 hours. This Wikipedia article on diesel engines explains why piston ring gaps matter, but the parts catalog tells you which ring set the factory specified.

Use the Detail Codes to Narrow Your Search

Page 3 of the manual shows a table: Detail Code D2 corresponds to FD30-16, G1 to FG20/25-16, and so on. When you open any figure page, that detail code appears at the top left. If your machine serial number falls within the range listed on that figure, the parts shown are correct for your unit. If not, you need to find the later revision figure – Komatsu released updates without changing the model name. That level of granularity is what you pay for. The catalog also uses symbols: a superscript alternative part number (shown as “OF-” or “BX-4”) indicates a superseded part that can replace the original. Always check the serial number column; a part may fit only up to a certain serial break, then a new number takes over. Ignoring that gets you a starter motor with the wrong mounting flange.

Komatsu OEM vs Aftermarket Parts Lists: Why It Matters

Aftermarket catalogs often compile parts from multiple sources and merge serial number ranges. They show you a single part number for a hydraulic pump that actually had three different pump suppliers during the production run. The OEM Komatsu catalog – the one you are looking at – splits those revisions clearly. The part number changes when the manufacturer changed the pump shaft spline or the seal diameter. If you order the wrong pump because you trusted a third-party list, you get to drop the transmission pan again. This manual eliminates that risk. It is printed by Komatsu, distributed through their dealer network, and carries the factory part numbering system. No reprints, no scanned copies, no generic compilations. You get the same 512 pages that sit in the Komatsu parts counter.

For related manuals, check the Komatsu FG/FD Series Forklift Parts Catalog if you also work on FD diesel models. The Komatsu BX50 Series Forklift Parts Manual covers a different platform but shares many engine and hydraulic components. And the FAI 67-80DT Hydraulic Steering Piston Parts List is a specialized cross-reference for steering cylinder rebuilds. If you want to understand how internal combustion engine parts catalogs are structured, read this Wikipedia article on diesel engines for general background.

Does this parts catalog include repair procedures or torque specs?

No. This is a parts catalog only. It lists part numbers, quantities, and serial number ranges. No service instructions, no torque values, no diagnostic steps. For repairs you need the corresponding shop manual.

How do I know if a part number from this catalog is still available from Komatsu?

Check the part number against your local Komatsu dealer’s inventory system. The catalog shows the OEM number that was used at time of manufacture. Many parts remain available, but some may be superseded. The manual marks supersessions with a special symbol (OF- or BX-). Always verify availability before ordering – the catalog does not list discontinued status.

Access the Factory Manual. That is the only way to get the actual page-by-page scans, exact part numbers, and serial number splits that match your shop’s fleet. Print the pages you need, tape them to the toolbox, and stop chasing wrong parts.