Description

Aichi ISR403, SR-123 Parts Catalog

I’ve been turning wrenches for 28 years, and one thing I can’t stand is a parts catalog that leaves you guessing. The Aichi ISR403, SR-123 Parts Catalog is the real deal – 118 pages of OEM breakdowns direct from Aichi Corporation. No third-party reprints, no sloppy scans. This is the same book the dealer techs pull off the shelf when a customer rolls in with a busted crawler or a leaking boom cylinder.

118 Pages of Parts Breakdown

Every major system gets its own section. You’ve got crawler, travel motor, Engine & Mounting, Fuel Tank, pump assembly, swing reducer, boom, basket, control boxes, electric parts, valves, cylinders, tubing, and decals. The table of contents lists each sub-section – for example, under “BOOM” you’ll find five separate lists covering boom structure, boom cover, basket, and tubing. That level of detail tells me the engineers who wrote this expected mechanics to actually use it.

Does This Catalog Cover the Engine and Fuel System?

It does. The Engine & Mounting section has three parts lists: mounting brackets, engine components, and hardware. The Fuel Tank list is a single page but it includes the tank itself, sending unit, lines, and clamps. If you’re rebuilding a unit that sat in a field for years, you’ll need these part numbers to order replacements. The catalog also covers the Fuel system indirectly through the pump assembly and tubing sections – the basket tubing and boom tubing get their own lists, which is critical for tracing hydraulic and fuel lines.

How to Use the Foreword and Abbreviation List

Flip to page 2 and you’ll find the foreword – it explains the level system (1 for assembly, 2 for components, 3 for subparts) and the quantity column (AR means as required). The abbreviation list on page 3 decodes things like ASSY, BRG, BKT, CYL, P/K, R/K. Don’t skip this part; if you order a “P/K” without knowing it means packing kit, you’ll get the wrong part. The catalog also uses symbols like A (assembly only), N (semi-finished), C (substitute parts), and K (service kit component). Page 4 shows the first actual parts list – crawler group with track shoe and drive unit part numbers.

Crawler, Boom, and Hydraulic Sections: What You Get

For a self-propelled aerial platform like the ISR403, the undercarriage and boom are where most wear happens. The crawler section has three lists: track shoes, drive units, and hardware. The boom section has five lists covering the main structure, boom cover, basket mounting, manual box, and lower/upper control boxes. Hydraulic parts are spread across valve lists (solenoid valves, priority valve, combination valve, double pilot check valve, counterbalance valve) and cylinder lists (elevation, extension, leveling upper/lower). Each list gives the part number, description, quantity per machine, and applicable serial number range. For example, the elevation cylinder list shows the cylinder assembly, piston rod, seals, and mounting pins.

3 Reasons to Choose OEM Factory Parts Catalog

First, the illustrations are drawn from factory CAD files – you see exactly how the boom brackets mount to the turntable tubing. Second, the part numbers match what the dealer uses; aftermarket catalogs often renumber components or leave out superseded numbers. Third, the serial number application is precise. The cover on page 1 shows “Applied Serial No. 654724 ~” meaning this catalog covers machines from that serial forward. If you have an older unit, you need a different book. OEM documentation gives you that boundary; third-party reprints usually omit it.

Source Validity: Why Aftermarket Copies Fail

I’ve seen online sellers slap a “Parts Manual” label on a scanned, blurry copy of a 15-year-old catalog with missing pages. This is a direct OEM PDF from Aichi – the same file you’d get if you ordered from the Automotive Industry Overview or directly from the manufacturer’s technical service department. The file name itself – AICHI_SR-123-ISR403_Parts_Catalog_ja-en-50214019189.pdf – includes the dual-language Japanese/English content. If you need a part for an Aichi boom lift, this is the reference point.

Related manuals you may want on the same shelf: AICHI PARTS LIST MODEL SR123/ISR403, AICHI Self Propelled Aerial Platform Service Manual for repair procedures, and Aichi SR18AJ SR21AJ SR18A SR21A Parts Catalog – 300pp OEM if you work on those models as well.

For a broader perspective on how OEM parts catalogs fit into the repair ecosystem, check the Automotive Industry Overview on Wikipedia.

FAQ

Can I order parts directly from this catalog?

Yes, but with a catch: the part numbers are for Aichi original parts. You give the dealer the machine model, serial number, part number, and quantity. The foreword says to include the serial number because some parts change after a certain build date.

Does it include torque specs for bolts?

No. This is a parts catalog, not a service manual. You need the service manual for torque values and repair sequences. The parts catalog only gives you the correct bolt part number and quantity.

What does the symbol ‘A’ in the remarks column mean?

Parts with an ‘A’ are supplied only as complete assemblies – not as individual pieces. If you need a seal inside a boom cylinder, you might have to buy the whole cylinder assembly unless the individual seal is listed separately elsewhere.

Is this manual in English or Japanese?

The catalog is bilingual – Japanese and English. The foreword, abbreviation list, and column headers appear in both languages. Part numbers and descriptions are numeric or English-based. If you can read English part names, you’ll be fine.

You want to get this job done without playing games with mismatched parts. Access the Factory Manual now and keep it on the tablet or print it for the shop – just don’t lose it under a pile of oil rags.