Description

White MSB, MA, WC, MY20-30, MY40-50 1977 Parts Catalog

If you’re holding a White MSB, MA, WC, MY20-30, MY40-50 1977 Parts Catalog, you’re looking at the only source I trust for ordering the right steel for a high-free-lift triplex mast. I’ve seen guys waste a full day because they grabbed the wrong roller pin or used an aftermarket bearing cap that didn’t fit the I-beam channel. This 18-page OEM document kills that guesswork. Printed June 1977 by White Motor Corporation, Hopkins, Minnesota – not a scanned reprint, not a third-party summary.

Before you tear into a mast rebuild on an MSB or an MA, you need to know exactly which part number matches the serial number range on your truck. Page 2 shows the upright for MSB, MA, WC & MY20-30 with a 2000–3000 lb capacity. It lists every bolt, shim, sheave, and latch – including the 35A14246 rail roller pin and the 20-3009195 latch. Aftermarket catalogs will lump those into a generic “roller kit” and leave you hunting for the missing piece. This catalog gives you factory references. No shortcuts.

Triplex Mast Breakdown: Uprights, Carriages, and Cylinders

Chapter headers are exactly what you’ll find on the workbench. Upright for MSB, MA, WC & MY20-30 (pages 2-3) covers the 4-3/8″ I-beam group. Uprights for MA & WC30-50 and MY40-50 (pages 4-7) handles the bigger lifts. Carriages for Uprights (pages 8-9) lists the weldments and fork stops. Then the Lift Cylinder, 4″ Dia. for MSB, MA, WC & MY20-30 (pages 10-11) and Lift Cylinder, 4-3/4″ dia. for MA & WC30-50 and MY40-50 (pages 12-15) – each with its own cylinder head, piston, and seal part numbers. Variable Parts Charts for Uprights (pages 16-18) let you cross-reference by serial number prefix. That is the kind of detail that keeps a mast from dropping sideways.

Why OEM Beats Aftermarket Reference

I’ve had aftermarket parts catalogs show a part that “fits” only to find the shoulder diameter is off by 0.015″. This catalog came from the factory floor at White Materials Handling Division. The part numbers match the actual production run in 1977. The 35A12635 dog welded to the outer rail? That’s the exact weldment they installed at the plant. When you’re ordering parts for a MY20-30 or a MY40-50, you use the chart on page 16 to pick the correct rail assembly. No guessing. No cross-referencing to a generic listing that covers three different brands. This is the source document. White MSB Series Fork Lift Truck Parts Catalog gives you the same level of specificity for other White series.

Lift Cylinder Data: 4-Inch and 4-3/4-Inch Bore

The cylinder sections alone save you from ordering the wrong seal kit. Page 10 shows the 4″ bore cylinder assembly (39A2692) with a 36A14308 head, 35A14048 sheave, and 20-3002962 retainer plate. Page 12 lists the 4-3/4″ bore version for the heavier capacity trucks. Each page includes the grease fitting specifications – 1/8″ straight fittings for the mast pivot, plus the 90-degree ones for the MY models. If you’re rebuilding a lift cylinder on a WC or MA, you need those part numbers to order the right piston seals and wiper rings. Missing that? You’ll be swapping cylinders twice.

Does This Manual Cover the Fuel System? (FAQ)

Does this parts catalog list engine components or just the mast?

It covers the triplex I-beam mast – uprights, carriages, lift cylinders, and variable parts charts. No engine, transmission, or electrical sections. If you need the powerplant, look for a separate service manual.

Will the part numbers work for a 1980 White MY40-50?

Possibly, but this catalog is published 1977 and covers specific serial number ranges (e.g., MSB 4575B3-4585B3). For later production, you’d want the corresponding later catalog. Always verify with the chart on page 16-18.

Can I use this to rebuild a lift cylinder?

Yes. The cylinder sections (pages 10-15) give exploded views with part numbers. You still need the service manual for torque specs and disassembly procedures – this is a parts list, not a repair guide.

Is this a PDF format or a physical book?

Digital access. You get the full 18-page PDF as originally scanned from the 1977 print. No watermarks, no missing pages.

3 Reasons to Choose OEM Documentation

First, the part numbers are factory issued – cross-reference to current inventory becomes reliable. Second, the exploded diagrams show exactly how the triplex mast assembles, including the roller shim selection (.010, .015, .030 thick). Third, the variable parts charts (page 16) eliminate the “maybe it fits” problem. White MY20, MY25, MY30, MY40C Parts Catalog – OEM Forklift Part Numbers extends that reliability to other White models.

Understand the Mast Before You Order Parts

The high-free-lift triplex uses a nested I-beam design. The outer rail, intermediate rail, and inner rail each have dedicated roller assemblies. On page 2 you’ll see the 35A14244 roller (3-1/4″ diameter) and the shim sets. If you skip the shim spec, you can end up with chain slap and premature sheave wear. The 35A14046 bearing on the cylinder head sheave must match the 2-3/16″ diameter. The manual calls out every fastener – hex bolts, countersunk screws, 12-point head bolts – with thread size and length. White MA20B, 25B, 30SB 1979 Parts Catalog – OEM Factory Specs carries the same obsessive part-number accuracy for later production.

For context on why OEM factory data matters in industry, Automotive Industry Overview discusses traceability standards. The internal combustion engine that powers these trucks is covered separately, but the mast components here are pure mechanical iron – Internal Combustion Engine pages won’t help you with the cylinder sheaves.

Bottom line: if you’re ordering parts for a White forklift with a triplex mast – MSB, MA, WC, MY20-30, or MY40-50 – this 1977 parts catalog is the key to getting the right steel the first time. Access the Factory Manual.