Description

Allis-chalmers 640, 644 1980 Parts Catalog – Factory OEM

Looking for the actual part numbers and exploded views for a 640 Loader or 644 Forklift? I’ve wasted enough time on aftermarket catalogs that guess at dimensions and leave you holding a wrong bolt. This Allis-chalmers 640, 644 1980 Parts Catalog is the real deal – factory-printed, with every part called out by its OEM number. 212 pages of nothing but schematics, item callouts, and the hardware lists that tell you exactly which washer goes where. If you’re rebuilding a hydrostatic drive or tracking down a steering cylinder, this is what you need on the bench, not a photocopy of a photocopy.

7 Systems Covered – Real TOC Chapter Names

The index splits the machine into logical groups: AIR INTAKE & EXHAUST SYSTEM (muffler, manifold, air cleaner – page 47-51), COOLING SYSTEM (water pump, radiator, thermostat – page 53-59), DRIVE TRAIN (rear axle, planetary wheel assembly, parking brake – page 111-117), ELECTRICAL & INSTRUMENTS (wiring, alternator, starting motor, instrument panel – page 77-91), ENGINE (cylinder block, cylinder head, camshaft, piston & connecting rod, oil pump – page 21-45), ATTACHMENTS (loader buckets, grapple, pallet fork, return to dig – page 197-207), and CAB / HEATER (defroster fan, heater assembly – page 191-195). Each section shows the assembly in exploded view on the left page and the corresponding parts list on the right. You point to the item number, read the part number, and order it. That’s it.

Cylinder Head and Block – Page 23-25

The cylinder block and cylinder head breakdown starts on page 23. You’ll see the short block assembly, the sleeve (cylinder liner), piston rings, and the head gasket set. Page 25 lists the intake and exhaust valves, valve guides, and rocker arm shaft. If you’re pulling a head to re-ring an Allis-chalmers diesel, having the factory illustration keeps you from mixing up the pushrod and tappet order. I’ve seen guys spend two hours on a valve adjustment because they used a generic catalog – this manual shows the exact orientation of the rocker arm shaft, page 33. Don’t guess. Use the OEM drawing.

Electrical System – Wiring and Starting Motor Details

Wiring diagram? It’s not a separate fold-out – the electrical section (page 77) gives you the harness routing, battery cable size, and the starting motor mounting. Alternator fan and pulley are called out separately on page 81-85. Instrument panel, fuse block, head and tail lamp assemblies – all listed with the correct bulb numbers. If your 644 fork lift has a dead hourmeter, page 87 shows the fuel gauge, water temperature gauge, and hourmeter as individual items. You can order the exact gauge, not a universal replacement that needs wiring adapters.

Attachments and Options – Loader Buckets, Grapple, Manure Fork

Page 197 covers the loader buckets, pallet fork, and manure fork. The grapple – field installation kit – is on page 203. Return to dig valve is page 207. Thermostart cold-start aid is page 205. If you’re adding a grapple to a 640 loader, the manual shows the cylinder mounting brackets and hydraulic line routing. Aftermarket catalogs skip these details. OEM pages don’t.

Why Factory OEM Beats Any Aftermarket Catalog

I’ve tested aftermarket parts catalogs against this 1980 print. They drop hardware, misinterpret the “incl.” notations (page 2 of the foreword explains indented hardware is not included unless stated), and sometimes flip left/right thread callouts. OEM Allis-chalmers documentation is lithographed from the same printing plates the dealer network used. No reprints – this is a scan of the original July 1980 publication. The numerical index at the front lets you look up any part number and find its location grid. You’re not flipping blind.

If you’re serious about keeping a 640 Loader or 644 Forklift running, put this Parts Catalog next to your machine. Related factory manuals you should also have: Allis-Chalmers HD-6EP Parts Catalog – Factory OEM 374 Pages, Allis-chalmers HD21A 1965 Parts Catalog – Factory OEM, and Allis-chalmers HD16D, HD16DC 1970 Parts Catalog – OEM Factory Specs. For background on the industry standards these machines follow, read the Automotive Industry Overview and Automotive Industry Overview.

Does this catalog cover the engine serial number location?

Yes, page 3 shows engine serial number and unit serial number location diagrams for both models.

Can I use this catalog to order gasket sets?

Absolutely. Page 19 lists the top overhaul gasket set; page 21 lists the bottom overhaul set. Each includes the cylinder head gasket, oil pan gasket, and timing cover gasket with OEM part numbers.

What about the steering cylinder – is that in here?

The power steering cylinder is referenced under AXLE, STEERING & WHEELS but directs you to the HYDRAULIC SYSTEM section. The steering valve and control column are on page 119. You’ll need the separate hydraulic parts catalog for the cylinder breakdown, but the valve assembly is fully detailed here.

How does the numerical index work?

Each part number appears in the back numerical index with a grid location (page and grid letter, like 23-A). You go to that page, find the grid, and confirm the item number. It saves thumbing through 200 pages when you only need one bolt.

Order the factory-printed scan. Access the Factory Manual today and get the part numbers that fit the first time.