Description

Fiatallis HD-11G, HD-11GC 1971 Parts Catalog

Twenty-eight years in the shop, and I still see guys wasting a Saturday because they ordered parts from a reprint catalog that had wrong numbers. That’s how you end up with a piston pin that doesn’t fit or a seal that leaks after a week. This Fiatallis HD-11G, HD-11GC 1971 Parts Catalog is the original factory print – not a scan of a scan. 440 pages, published by Fiat-Allis themselves, covering serial numbers 101 and up. If you own an HD-11G or HD-11GC and you’re pulling a final drive or rebuilding the undercarriage, you need this on your bench.

Second Printing: What Changed

Page 2 of this catalog tells you exactly what was revised. The second printing (dated 11-71) is identical to the first except for pages 128A, 128B, and 273A, which were added in 1968. Plus all write-in changes from Parts Bulletins up to TPSD 117 are already included. That means you’re not hunting through bulletins trying to pencil in updates. It’s all baked in. If you’re working on an early HD-11GC with serial 6427 through 10000, those added pages cover the injection pump and other updates.

Parts Ordering: Follow the Procedure

Flip to page 5 and you get the ordering instructions straight from the factory. Give them the model and engine serial number – no exceptions. They list the part name and part number, and they tell you to confirm telephone orders in writing. That may sound obvious, but I’ve seen partial shipments because someone rattled off a number they misread from a faded copy. With this catalog, you read the exact number off the page. And they warn you: no credit on returned parts unless they’re shipped back to the dealer. That’s the real world.

Left vs Right Orientation: Factory Definition

A standard headache on crawler loaders is figuring left from right when you’re standing behind the machine. Page 5 sets it straight: “determined by facing the direction of forward travel.” That’s the same convention I teach every new kid in my shop. Attaching parts like bolts and washers are indented under the parts they attach. And if you see a square symbol, that part is also available in a packaged set – you can buy a whole seal kit instead of fishing for individual O-rings.

Additional Publications You Might Need

Page 4 lists other factory manuals you should own. The injection pump (PSB) has its own parts catalog, form 643833. The TR11 Ripper, 75 Cable Control Unit – separate books. Service manuals for the engine, clutch, torque converter, steering clutches, final drives – all listed by form number. If you’re doing a full overhaul, get the Service Manual for the Model 10000 & 11000 Engine (form 645121) and the Steering Clutches & Brakes manual (form 650433). This parts catalog works with those. You’ll also find relevant manuals on our site, like the Fiatallis HD-9 1989 Parts Catalog – OEM Factory Specs and the Fiatallis HD-6A, HD-6AG, HD-6B, HD-6E 1989 Parts Catalog for smaller models.

440 Pages of Factory Part Numbers

Every page in this catalog is a clean factory scan, not a reprint. The index starts at page 1 with the model identification: FIAT-ALLIS HD-11G / HD-11GC crawler loaders. From there it goes straight through 440 pages of exploded parts views and numeric part lists. You get the original artwork, the original callouts, and the original font. No third-party guesswork. I’ve been burned by aftermarket catalogs that listed a bolt with the wrong thread pitch – that doesn’t happen here. The Fiatallis HD-21 Crawler Tractor Parts Catalog is another example of the same factory standard for larger machines.

Aftermarket documentation? I don’t trust it. I’ve seen parts numbers that were transposed, missing digits, or outdated. This catalog is the same source the dealer parts counter uses (or used to use, before everything went digital). It’s printed in English, form 70635043. The note on page 2 explains that Allis-Chalmers and FIAT entered a joint venture in 1974, so older catalogs carry the FIAT-ALLIS name. That’s the official lineage. As discussed in the Automotive Industry Overview, proper documentation is critical for equipment longevity.

Does This Catalog Cover the Hydraulic Shovel System?

Yes, but partially. There is a separate service manual form 641546 for the shovel hydraulic system. This parts catalog lists components that are part of the loader attachment, but for full hydraulic troubleshooting you want the service manual. However, any part number you need for the hydraulic components – hoses, cylinders, seals – is in this book. The parts catalog is the parts catalog; it’s not a repair manual. That’s why you need both.

FAQ

Does this parts catalog include the engine itself?

Yes, engine parts are listed, but the injection pump uses a separate catalog (form 643833). The main engine components – block, head, pistons, liners, gaskets – are all in this 440-page document.

Can I use this catalog to order parts for an HD-11GC built after 1974?

For serial numbers 101-up, yes. The catalog covers all production through the publication date (1971) and includes bulletins up to TPSD 117. Machines built after 1971 may have running changes not captured here, but most common parts remained the same. Always verify by serial number with your dealer if the machine is late production. For reference, look at the Automotive Industry Overview to understand how manufacturers handled supersessions back then.

When you need to identify a seal, gasket, bearing, or bolt for your HD-11G or HD-11GC, stop guessing. Get the catalog that came from the factory floor. Access the Factory Manual and put the right part in your hand the first time.