Description

Aichi SR12B, SR12BJ, ISR40B, ISR40BJ Parts Catalog – Stop Ordering the Wrong Part

Ordering parts for an Aichi crawler boom lift without the factory catalog is a gamble I’ve seen cost guys a full week of downtime. You pull a seal, find a number crudely stamped on it, punch it into a parts website, and three days later you get a box with something that kinda-sorta fits. That’s parts roulette, and it’s expensive. Aichi SR12B, SR12BJ, ISR40B, ISR40BJ Parts Catalog ends that. It’s the same binder that Aichi Corporation’s parts counter in Ageo, Japan uses. 268 pages of exploded diagrams, genuine part numbers, and the level-coded assembly structure that tells you exactly which nut belongs to which sub-assembly. No translations lost in the mail – this is the original Japanese and English print.

If you’re working on an SR12BJ or an ISR40B, you’ve likely noticed that undercarriage parts, boom sections, and control boxes vary by serial number. The catalog separates standard and tip configurations for the basket base, counterweight, and rotary actuator. You don’t need to call a dealer and hope the guy on the phone reads the right revision. You get the same drawing number and group number system the factory uses every day.

FRAME and Undercarriage: Finding the Right Part Numbers

The undercarriage on these machines takes a beating. The catalog lists the FRAME section separately for crawler tubing, roller C, roller T, travel motor, swivel joint, shoe, front idler assemblies (right and left), and spring assemblies. Each listing shows a breakdown of the assembly with level 1 for the parent part, level 2 for components, and level 3 for sub-components. That matters when you need the idler spring but not the whole idler frame. The parts list for TRAVEL MOTOR has three separate lists because the motor changed across serial number breaks. Skip the cross-reference – the factory tells you exactly which serial number range each motor list covers.

TURN TABLE and Engine Mounts: Sorting the Lists

Engine, radiator, fuel tubing, suction tubing, and engine control – each turn table system gets its own list. I counted three separate TURN TABLE lists in the table of contents, plus dedicated sections for the rotation gearbox and filters. If you’re trying to find the correct fuel line for an ISR40BJ, you’ll look under TURN TABLE(FUEL TUBING) LIST 1 and LIST 2. The catalog even separates standard and tip counterweights under WEIGHT(FRAME). The level column prevents you from ordering the counterweight bracket when you only need the bolt.

BOOM and Basket Assemblies: Standard vs Tip Configurations

A big headache for rental fleets: the fly jib tip and the fly jib cylinder tip. The catalog has separate listings for FLY JIB TIP (LIST 1 and 2) and FLY JIB CYLINDER TIP (single list). Boom sections include BOOM LIST 1 through 5, plus BOOM(TUBING) for the hydraulic lines that run inside the boom. The basket section shows BASKET BASE STD and BASKET BASE TIP, each with up to four lists. You see that difference? The STD uses one rotary actuator configuration; the TIP uses another. Order from the wrong list and the mounting holes won’t line up.

CYLINDERS and Hydraulics: Don’t Guess the Seal Kit

The elevation cylinder, leveling cylinders (upper and lower), extension cylinder – standard and tip variants are all separated. ELEVATION CYLINDER STD and ELEVATION CYLINDER TIP are different drawings. The combination valve and turn table tubing lists complete the hydraulic picture. Page 3 of the catalog explains the remark symbols: “A” means the part is only supplied as an assembly, “N” means semi-finished, “R” means a reworked part with a different number. I’ve seen guys order the “N” version of a cylinder rod and then complain it doesn’t fit because they needed the finished version. Read the remarks column before you click buy.

DECALS and Options: The Details That Matter

Aichi includes DECALS STD and DECALS TIP with multiple lists. Safety decals change across years and jurisdictions. If you’re restoring an SR12B or replacing a faded warning label, the catalog gives you the correct part number for your machine’s configuration. Options like the generator, working light, receptacle, remote control, crawler pad, and boot cylinder are listed toward the back. You won’t have to call a dealer and ask if the generator option is compatible with your ISR40B – the catalog shows the harness and bracket part numbers.

OEM Source: Why an Aftermarket Cross-Reference Won’t Cut It

This is not a third-party rehash. It’s a direct print from Aichi Corporation, the same one you’d get if you walked into their R&D center in Ageo. The file name – AICHI_SR12B-ISR40B-SR12BJ-ISR40BJ_Parts_Catalog_ja-en-50214019194.pdf – tells you it’s authentic. Aftermarket catalogs copy the illustration but leave out the level column, the remark symbols, and the serial number applicability. That’s how you end up with a part that fits a 2015 machine on a 2018 chassis. Factory documentation is the only way to guarantee you’re ordering the revision your machine needs.

Don’t get me started on aftermarket “interchange” lists. They’re built by someone who never torqued a bolt on an Aichi. Use the factory catalog, get the right number, move on.

Related manuals worth having on the shelf: Aichi SR12B SR12BJ ISR40B ISR40BJ Operators Manual covers daily operation and safety; Aichi SR12B/SR12BJ Crawler Boom Lift User Manual goes deeper into controls; Aichi SR12B/ISR40B/SR12BJ/ISR40BJ Parts List is the same catalog you’re looking at now. For the broader context of equipment maintenance, see the Automotive Industry Overview and Automotive Industry Overview.

FAQ

Does this catalog include part numbers for the SR12BJ model?

Yes, it covers SR12B, SR12BJ, ISR40B, and ISR40BJ.

How is the catalog organized to find a specific part?

It uses a level system: level 1 is the main assembly, level 2 is its components, level 3 is sub-components. Eleven illustration indexes help you locate the drawing. Each section – like TURN TABLE or BOOM – has multiple lists separated by standard/tip configurations and serial number breaks. The remarks column tells you if a part is only sold as an assembly, semi-finished, or if a substitute exists. Page 3 of the catalog explains all symbols in English. Use the INDEX tables at the front (INDEX 1 through 5) to find the exact drawing number, then cross-reference to the list for the part number.

If you’ve got an Aichi on the lift and the part number is a question mark, this is the document that ends the guesswork. Access the factory manual from AutoRepairManuals and keep it on the bench next to your laptop. You’ll use it every time something breaks.