Clark Equipment 125 IIIA Parts Catalog – Factory OEM Manual

Ever order a brake line for a Clark Equipment 125 IIIA and get the wrong bend? Then you pull the old one, realize the new one doesn’t match, and the machine sits another week. I’ve seen it a hundred times. This Parts Catalog from Clark Equipment – the 125 IIIA – is what the dealer uses to pull the exact part number. It’s 136 pages of exploded diagrams and OEM numbers. No guesswork. You want the right part the first time, you need the factory book.

Brake Group: More Than Just Shoes

The Brake Group section (starting at page 1B4) covers the front and rear brake assemblies, air lines, valve, controls, and the parking brake. If you’re replacing a brake chamber or an air line, the diagram shows every bolt, seal, and bracket with a part number. The Parking Brake Controls section (page 1B13) lists the levers and linkages that often wear. Without the OEM drawing, you’re guessing at which spring or pin goes where. I’ve had guys wire-tie parking brakes together because they ordered the wrong lever – this manual stops that.

136 Pages of Factory Exploded Views

You don’t get blurry photocopies or third-party redraws here. Each system – from the Axle Group to the Wiring Group – is laid out the same way the parts counter sees it. The Index on page 2 lists every assembly: Accelerator Pedal, Air Cleaner, Muffler, Axle Front/Rear, Differential, Planet Carrier, Converter, Cylinders, Hydraulic System, Transmission, and more. If you need the part number for a steering drag link (section 2A11), it’s in there. No calling around, no cross-referencing aftermarket catalogs that don’t list supersessions.

Hydraulic System – Following the Hoses

Hydraulic leaks on a tractor shovel cost you time and fluid. The manual breaks down the Hydraulic Oil Reservoir (page 1E11), filter assembly (1E13), and the bucket/boom circuits (1F2). It also covers the steering system (1F8) and transmission/converter circuit (1F12). Each hose fitting, seal ring, and pump has its own illustration. When you’re ordering a new boom cylinder (1D4), you verify the mounting bracket by sight on the page – then order. No returns.

Transmission Group: Clutch Pack Identification

The Transmission Group (starting at 2B2) goes through the assembly, case, internal tubing, control cover, and clutch groups. That’s First & Second Clutch (2B7), Input/Reverse/Third & Fourth (2B8). If you’re rebuilding the transmission, you need the clutch plates and seal part numbers. The manual also shows transmission control levers and linkage (2B9) – critical if the shift pattern is sloppy. One wrong clutch disk can cost you a second teardown.

Does This Catalog Cover the Parking Brake Controls?

Yes, and explicitly. Pages 1B13-1B14 show the Parking Brake Controls and Lever Assembly. The drum, the shoes, the cable – all listed. The Brake Valve & Controls (1B10) and Brake Air Lines (1B6) are separate sections so you don’t confuse the service brakes with the parking brake. Aftermarket catalogs sometimes merge them into one generic diagram – that’s how you end up with a spring brake chamber that doesn’t fit.

Why a Factory Parts Catalog Beats Aftermarket Print

I’ve been burned by aftermarket parts books that flip left/right or skip sub-assemblies. This manual was printed by Clark Equipment for the 125 IIIA model. It includes the original index, the original page numbering (like 1B4, 2C14), and the part numbers that match the OEM supply chain. The Wiring Group (2C7-2C14) even has the circuit diagram on page 2C14 – you can trace the horn, foot switch, hourmeter, and battery cables without a multimeter. That’s the difference between fixing it and putting it on a hook.

One more thing: the manual tells you on every page: “WHEN ORDERING PARTS, ALWAYS STATE MODEL AND SERIAL NO. OF MACHINE.” That’s not a suggestion – that’s how you don’t get a 125 IIIA part for a 125 IIIB. Print the page, call the dealer, read the number. Done.

Can I use this catalog to rebuild my transmission?

Yes – it lists every clutch plate, seal, and bearing with part numbers.

How do I find the correct part for my specific serial number?

The manual has a blank page at the front to record your machine’s serial number. When you look up a part, cross-check the assembly page with your machine’s serial range – the manual covers all 125 IIIA builds but some sub-assemblies changed during production. Always reference “Model 125 IIIA” when ordering. The index shows each section page number; flip to that page and match the illustration to what you see on your machine. If the diagram shows a bolt pattern that doesn’t match your serial number range, the part may have been updated. Call Clark Equipment with the part number from the page – they can verify supersessions. Starting without the serial number is asking for a return label.

Download the Factory Manual and stop ordering parts by guesswork. You’ll have the right part number before you pull the old one off – that’s the only way to keep a tractor shovel earning its keep.

Related Manuals

• Clark 125 IIIA Parts Manual Articulated Tractor Shovel
• Michigan Model 125 IIIA Articulated Tractor Shovel Parts Manual
• Clark Equipment 75B 1989 Parts Catalog – OEM Factory Manual

For more context on how OEM documentation fits into the Automotive Industry Overview, see the Automotive Industry Overview page on Wikipedia.

Clark Equipment 125 IIIA Parts Catalog

If you are tearing down a 125 IIIA articulated tractor shovel and need a part number, do not trust some third‑party parts list. I have seen too many mechanics order the wrong brake chamber because they used aftermarket cross‑references. This Clark Equipment 125 IIIA Parts Catalog – 226 pages of factory‑issued part numbers and exploded views – will keep you from making that mistake. Every diagram comes straight from Clark Equipment’s own engineering drawings, not a reprint of a reprint.

Accessories, Engine – Cummins and G.M. Sections

The catalog splits the engine accessories into two separate headings: “Accessories, Engine — Cummins” and “Accessories, Engine — G.M.” Each gets its own page range (pages 2 and 3). If you are working on a Cummins‑powered 125 IIIA, you flip to page 2. For the G.M. variant, page 3. The same approach applies to air cleaners, fuel tank caps, and the transmission converter filter cartridge kit. No generic “fits all” listings. You pick your engine, you get the correct part number.

Brake Systems: Air Lines, Valves, and Slack Adjusters

Brake components are documented by engine type as well. “Brake Air Lines — Cummins” appears on page 73; “Brake Air Lines — G.M.” on pages 75 and 77. The Air Brake Valve gets its own entry on page 78. If you need the slack adjuster, it is listed on pages 57 and 63 (shared with the axle sections). The manual shows the valve, the air chamber, and the reservoir with OEM part numbers. I have seen shops waste half a day hunting for a parking brake valve – this catalog points you to the exact piece.

Skip the third‑party catalogs. They cost you time.

Transmission and Converter Components – Six Sub‑assemblies

The transmission section covers the case (page 44), the control cover assembly (page 47), the air breather (page 43), the oil fill cap (pages 37, 39), and the charging pump for the converter (pages 49, 51). The first‑and‑second clutch group is on page 45; the input‑reverse‑third‑and‑fourth clutch group is on page 46. If you are rebuilding the Transmission, you need the exact clutch pack part numbers. This catalog gives them, and it includes the torque converter air breather (page 51) and the cartridge filter kit references (pages 2, 37, 39). You will also find the “Cap, Transmission Oil Fill” for both engine options – a detail many aftermarket lists miss.

Hydraulic System: Bucket, Boom, and Pump Assembly

The bucket and boom hydraulic pump is covered on page 89, the full bucket and boom hydraulic system on page 91, the bucket cylinder assembly on page 92, and the boom cylinder assembly on page 93. The control valve assembly spans pages 95 and 97. Each page includes an exploded view with callouts for every seal, piston, and fitting. Air valve assembly for the bucket leveler (page 16) is separate, so you do not have to dig through the whole hydraulic section to find that small component. The bucket assembly data (page 15) lists cutting edges and bucket parts. This is the kind of organization that saves a Saturday afternoon.

Clark Equipment 125 IIIA Parts Catalog – Axle Assemblies and Torque Data

Front drive axle assembly is on pages 55 and 57; rear drive axle on pages 61 and 63. Each axle page includes the slack adjuster and air chamber details. Torque values for axle mounting bolts appear in the front drive axle section (page 55). A factory parts catalog does not always list torque specs, but this one includes them for critical fasteners. You can also find the “Brake Assembly — Front and Rear” on page 67 and the parking brake assembly on page 68. The parking brake controls are on page 71. Having these part numbers matched to the correct torque data means you can order the right hardware and install it to factory spec.

Why Factory Parts Catalogs Beat Aftermarket Versions

Aftermarket parts sources often combine multiple models into one PDF, or they skip pages to save space. This Clark Equipment 125 IIIA Parts Catalog is the original factory print. It covers machine serial numbers 404A101 and after (Cummins) and 403A101 and after (G.M.). You get the exact part numbers for your specific serial number range. The document includes a full table of contents, page numbers matching the original binder, and detailed exploded diagrams. If you want to understand the Clark Equipment 125 IIIA 1974 Parts Catalog – OEM Factory Manual or the Clark Equipment 125 IIIA Parts Catalog – Factory OEM Manual, this is the source. For a related model, check the Clark Equipment 75B 1989 Parts Catalog – OEM Factory Manual. The automotive industry relies on precise documentation; see the Automotive Industry Overview for context on OEM standard practices. Automotive Industry Overview

Frequently Asked Questions

Does this parts catalog include torque specifications?

Yes, for certain critical fasteners such as axle mounting bolts (page 55) and brake assembly hardware. The manual is a parts catalog, not a service manual, but it does list torque values where needed for correct part selection and installation.

Can I use this catalog for a 125 IIIA with a different engine than listed?

Only the Cummins and G.M. engines are covered. The serial number ranges are clearly stated. If your machine has a different powerplant, this catalog will not apply.

This 226‑page original factory document is the most reliable way to identify and order parts for the 125 IIIA. Do not rely on a generic parts lookup. Download the Factory Manual from AutoRepairManuals and keep a copy on your shop tablet. You will burn less time looking up parts and more time turning wrenches.