Description

Clark-hurth 280IIIA 1978 Parts Catalog – Factory Grid-Indexed Part Numbers

If you’re tearing into a Clark-hurth 280IIIA Tractor Dozer and you don’t have the original parts catalog from 1978, you’re working blind. I’ve seen guys order three different axle seals because the aftermarket listings don’t match the actual hardware. This Clark-hurth 280IIIA 1978 Parts Catalog is the 135-page factory document that tells you exactly which part number goes where. Not a reprint, not a scan of a scan—this is the OEM grid-index system the factory used. You get the same illustration numbers, write-up columns, and grid descriptions that Clark-hurth mechanics had when these machines were new. That matters when you’re trying to keep a 1978 dozer running on a 2024 budget.

Engine Controls Model 4047 and 4048: What the Manual Shows

The catalog lists engine controls separately for Model 4047 and Model 4048 (pages 1A5–1A8). Each control group gets its own illustration number—TP 2688 for Model 4047, TP 3168 for Model 4048—and a write-up column that tells you whether the illustration is included or not. You also get the air cleaner connections and air cleaner assemblies for both models. If you need a throttle cable bracket or a fuel shutoff lever, the grid reference points you to the exact drawing. No flipping through generic diagrams wondering if your engine variant is covered. The Engine mounting section on page 1E14 lists the brackets and isolators with part numbers you can cross-check against the hardware on your machine.

Axle Assembly – Front and Rear: Grid References You Can Trust

Axle assemblies are split into front and rear sections (1B1–1B3, 1B6–1B8). Each includes differential and carrier assemblies (1B9–1B12) and planet carrier assemblies (1C1–1C2). The catalog uses a three-column system: Grid Description, Illustration No., and Write Up. For the front axle, the illustration number is TP 2077; for the rear, TP 2906. When the Write Up column says “None” or “Yes,” it tells you whether the illustration is printed on that page. That’s how you avoid ordering a planet carrier that looks right in the aftermarket photo but doesn’t fit the 280IIIA housing. I’ve watched a shop lose four hours because a parts guy chased the wrong differential case. This catalog stops that before it starts.

Brake System – Main Model 4048: Factory Diagrams Only

The brake system sections cover front and rear brake assemblies (1C7–1C8), parking brake assembly (1C9), foot controls (1C10), and main brake lines (1C11–1C14). For Model 4048, the main brake system diagram is listed on 1C14 with no illustration number—that means the drawing is built into the page itself. If you are replacing a brake shoe or a hydraulic line, you need the factory routing. Aftermarket catalogs often consolidate brake line layouts across multiple models, which leads to wrong tube bends. This manual gives you the exact brake line routing for the 280IIIA, with separate listings for Models 4047 and 4048 so you don’t mix up the air brake valve (1D3) or the parking brake linkage (1D1).

Torque Converter and Pressure Regulating Valve Assembly

Torque converter coverage spans pages 1D13–1E2. You get the converter assembly, the pressure regulating valve assembly (TP 2046), and separate sections for lift, pitch, tilt, and steering cylinders. The write-up column tells you which illustrations are included—most have a “Yes”, meaning the factory drawing is printed right there. If you need the part number for a pressure regulating valve seat or a cylinder piston, this is the only place you’ll find the OEM number that matches the 1978 production run. Aftermarket catalogs for the 280IIIA often skip the torque converter internals because they assume you’ll replace the whole unit. That assumption costs you money. With this catalog, you order individual seals, bearings, and valve components.

Hydraulic Lines – Transmission: No Guessing on Routing

Transmission hydraulic lines are covered in sections 2A5–2A8. The catalog lists the lines with illustration numbers (e.g., TP 2975, TP 2976) and a write-up column indicating whether the drawing is present. You also get the transmission control lines and the propeller shaft bearing assembly (2A10). The hydraulic system steering pump is on 2B5, and the main control valve (2D10–2E1) is broken into multiple sections. If you’re rebuilding a transmission and you don’t have the factory hydraulic line routing, you will end up with kinked hoses or wrong port fittings. I’ve seen it happen more times than I want to count. The grid index lets you jump directly to the exact assembly group without leafing through 135 pages blind.

Who Needs This Parts Catalog

If you own a 1978 Clark-hurth 280IIIA tractor dozer and you’re doing any kind of restoration, overhaul, or parts replacement, this catalog is the only reference that matches your machine’s original components. DIY mechanics, equipment owners, and home garage enthusiasts will find the grid-index system straightforward once you understand the prefix codes (1A through 2E). The catalog does not contain repair procedures or torque specs—it’s a parts identification tool. Use it alongside a factory service manual to order the correct parts the first time. Professional mechanics will appreciate the speed: scan the grid, find the illustration, pull the part number, call your supplier. No wasted billable hours.

Source Authenticity: OEM vs. Aftermarket

This is a factory-original Clark-hurth parts manual, printed in 1978, not a third-party compilation. The OCR excerpt from page 2 shows the internal memorandum confirming the parts manual stat number 95 for Model 280IIIA. Aftermarket parts catalogs for the 280IIIA are often generic reproductions that group multiple Clark-hurth models together, dropping individual variant listings. That leads to mismatched part numbers for engine controls, brake systems, and hydraulic lines. With the OEM catalog, you get the exact illustration numbers like TP 2688 and TP 2046 that reference the factory engineering drawings. If you rely on aftermarket documentation, you are relying on someone else’s interpretation. That’s not how I work, and it shouldn’t be how you work either. For broader context on industrial documentation standards, see the Automotive Industry Overview. The internal combustion engine used in these machines is well-documented; read about its history on Internal Combustion Engine.

Frequently Asked Questions

Does this manual include torque specifications or repair procedures?

No. This is a parts catalog, not a service manual. It provides part numbers, illustration references, and grid indexes. You need the separate factory service manual for torque specs and overhaul steps.

How do I use the grid index to find a part on my 280IIIA?

Each section has a three-column layout: Grid Description (e.g., “Engine Controls Model 4047”), Illustration No. (e.g., “TP 2688”), and Write Up ( “Yes” or “No” indicating whether the illustration is printed on that page). You look up the assembly group you need (e.g., “Axle Assembly – Front”), find the grid reference (1B1), then flip to that page. The illustration number is key: it matches the factory engineering drawing. If the Write Up says “Yes,” the drawing is included. If it says “No,” the drawing is not printed in your catalog but the part numbers are still listed. Use the grid description and part numbers to order. The catalog also includes a master index at the start (1A1 and 2A1) that cross-references all sections.

Related Manuals

• Clark-hurth L320 1991 Parts Catalog – 690 Pages OEM Specs
• Clark-hurth 85III 1965 Parts Catalog – Factory OEM Specs
• Clark-hurth 85A, 85A1 1978 Parts Catalog – OEM Factory Specs

If you’re ready to stop cross-referencing bad aftermarket numbers and start ordering parts that actually fit, access the factory manual. Get the Clark-hurth 280IIIA parts catalog in your hands before you turn another bolt.