Komatsu WA600-1-A(S/N 10001-UP)

The WA600-1-A (S/N 10001-UP) is a large-class Komatsu wheel loader, part of the WA400-and-up large-loader group in Komatsu's lineup. Komatsu built this production run in Japan from roughly 1987 to 1989. It runs a mechanically governed Komatsu S6D170-1D inline six-cylinder turbocharged diesel of 23.15 L (1,413 cu in) displacement; later chassis within this same numeric run switched to the S6D170-1D-A engine build, with no electronic engine control on either. Operating weight in standard general-purpose bucket configuration runs around 39.2 t (86,400 lb); treat this figure as approximate for this exact serial range and verify against the machine's dataplate or your dealer. The WA600-1 was the first entry in Komatsu's WA600 large-loader line, so it has no earlier WA600 predecessor. The -A designation covers the standard bucket configuration among several parallel WA600-1 catalog editions built on overlapping serial blocks alongside it, including a severe-duty/regional-spec edition, log-handling L, LC, and LE editions, and a supplement listing, each carrying its own serial range and work-tool setup.

Komatsu kept building on this basic large-loader package after the -1: further revisions, then the WA600-3 (mid-1990s to mid-2000s), the WA600-6 (mid-2000s to late 2010s), and today's WA600-8 all trace back to this original series. Each later generation swapped the mechanical governor and inline injection pump used here for an electronically controlled SAA6D170E-family engine, added electro-hydraulic joystick controls, and grew steadily heavier and higher in bucket capacity as emissions rules tightened through the Tier and Stage programs, eventually gaining KOMTRAX telematics and Komatsu's SmartLoader Logic. None of that electronics layer exists on this 1987-89 edition, which is part of its appeal on the used market: fewer sensors and no engine-management wiring to chase, against the tradeoff of decades-old parts and thin factory documentation. Working examples still turn up in quarry, forestry, and heavy-yard duty, and parts demand centers on wear items: pins, bushings, seals, ground-engaging tools, and torque-converter or engine rebuild components. Matching the exact serial plate before ordering matters more here than on a newer, single-catalog machine, since several parallel WA600-1 editions share overlapping serial blocks.

Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.