Case 580CK Series B, 35 Loader, 35 Backhoe 1979 Parts Catalog – OEM Parts Identification

Description

If you’re trying to rebuild the boom lockout hydraulics on a Case 580CK Series B and you’re guessing at part numbers, you’re wasting time and money. I’ve seen techs bolt the wrong valve on because they grabbed a generic replacement. Case 580CK Series B, 35 Loader, 35 Backhoe 1979 Parts Catalog eliminates that – it’s the same binder the dealer used when this machine was new.

Boom Lockout Hydraulics: Commercial-Cross Valves

Page 1 of this catalog lays out the boom lockout circuit for machines with backhoe serial numbers before 5219901. It’s a full parts breakdown – every O-ring, elbow, tube, and bolt. You get part numbers like L 51101 for the boom lockout valve and D 54195 for the tube from the backhoe valve to the lockout valve. Each item lists the required quantity, so you don’t over-order. The note about Hydra-Guide models? It’s right there. No aftermarket interpretation.

Serial Number Breaks: Identifying the Correct Valve Configuration

Case changed the boom lockout plumbing on later machines. Page 3 covers the group with backhoe serial numbers 5222134 thru 5222134, 5235801 thru 5237767, 5245351 thru 5245850, and 5245901 thru 5251150. Different part numbers for the tee, tube, and connector. If you ignore the serial range and order parts from the old page, your fitment will be off. That’s why this catalog stays on my bench – it stops you from ordering the wrong 90-degree elbow.

99 Pages of Verified Part Numbers

This Parts Catalog runs 99 pages. It covers the 35 Loader and 35 Backhoe along with the 580CK Series B tractor. You get hydraulic cylinder breakdowns (pages 293-299 referenced for boom cylinders), backhoe control valve parts, and the full loader attachment list. Every bolt size is imperial – 3/8″-16 NC x 3-1/4″ hex bolts, lock washers, hex nuts. You don’t need to convert metric. The factory printed this in April 1979, so the part numbers are original. No supersession guesswork from third-party reprints.

Why Use a 1979 OEM Parts Catalog Over Aftermarket?

Aftermarket parts books combine several years into one chart, then tell you to “check fitment.” That’s a trap. This catalog separates the boom lockout into two distinct hydraulic configurations based on exact serial number breaks. The aftermarket doesn’t do that. You get the wrong O-ring groove? You chase a leak. You order a tube that’s 1/4″ short? You’re bending line. I keep the OEM catalog because Case engineers validated every dimension. The automotive industry Automotive Industry Overview moves fast, but this iron hasn’t changed since ’79. Trust the original.

Cross-Reference Every Bolt and O-Ring Before Ordering

Look at the O-ring callouts: 218-5008 appears five times in the boom lockout circuit alone. Different locations, same part? Only if the catalog says so. The bolt lengths are precise – 13-652 is a 3/8″-16 x 3-1/4″ hex bolt, while 13-665 is also 3/8″-16 but a different length? Actually 13-665 is the same length? The catalog specifies it separately. Don’t assume. Cross-reference with the related Case 580CK Series B & Model 35 Loader Backhoe Parts Catalog and the full tractor breakdown in Case 580CK Series B Tractor Parts Catalog F1179. If you need the loader hydraulics, grab Case 35 Loader and 580CK Series B Parts Catalog. Stack them on the bench – that’s how you avoid pulling a fitting twice.

You Need This on Your Bench If…

You’re rebuilding a boom lockout valve, replacing hydraulic hoses, or piecing together a loader from a basket case. This catalog tells you the exact hose lengths – 36 inches (915 mm) for the hose to the boom cylinders, 23 inches (584 mm) for the crossover. No tape measure guess. The swivel joint part numbers are there. Every fastener spec is in imperial. And because it’s OEM, you can order parts from any Case dealer without having to bring a sample. The Automotive Industry Overview is for cars; this is for iron that earns on a jobsite.

Does this parts catalog include service procedures or torque specs?

No. This is a parts catalog – it lists part numbers, quantities, and hydraulic circuit diagrams. For torque specs and repair steps, you need a separate service manual.

Why are there two different boom lockout pages in the catalog?

Case changed suppliers from Commercial valves to Cross valves at a specific serial number break around 1979. Page 1 covers early machines (SN before 5219901), and page 3 covers later machines with five specific serial ranges. Use your backhoe serial number to pick the right page or you’ll order the wrong valve L51101 vs. an earlier variant.

If you work on these machines more than twice a year, stop borrowing the dealer’s PDF. Access the Factory Manual and keep the 99-page Parts Catalog on your tablet or in a binder. You’ll stop second-guessing part numbers, and your rebuilds will stay on schedule.