Description

Yanmar 3T75H-LTBS, 3T75H Parts Catalog

You ever order a head gasket, get it in the mail, and it doesn’t match because some aftermarket catalog had the wrong supersession? That’s why you need the factory parts catalog. This one – Yanmar 3T75H-LTBS, 3T75H Parts Catalog – is 64 pages of OEM part numbers, exploded diagrams, and ordering codes that match what Yanmar shipped from the factory. No cross-referencing your VIN against some third-party spreadsheet. No wasted time returning the wrong liner. Just raw, verified data.

I’ve been in the trade 28 years. I’ve seen techs throw away an afternoon because they trusted a generic parts list. That doesn’t happen when you’re reading off a factory print. The part numbers on page 2 for the cylinder block assembly (721551-01561) and the main bearing (121520-02100) are the same numbers the dealer punches into his system. Down to the O-ring 1A P-10.0 (24311-000100). If you’re tearing down a 3T75H-LTBS, you need this PDF open on your tablet before you place a single order.

Cylinder Block & Main Bearing Assembly (Page 2-3)

Page 2 lists the block assy, cylinder liner, head studs, nuts, and the oil sump assy with its drain plug. The OCR from the original document shows the exact item numbers: BLOCK ASSY, CYLINDER (721551-01561), LINER, CYLINDER (121551-01100), and the STUD, CYL. HEAD (121450-01210). You also get the shim set (121450-01951) and the non-asbestos gasket options (marked N on the line). If your engine is a K2032 variant, the PC code is Y00B4141 – that’s listed right on the info block. Page 3 has the exploded figure with callouts matching those parts. No mystery about which spring washer goes where.

Gear Housing Assembly and Studs (Page 4)

Page 4 jumps into the gear housing assy (729335-01612), including the plug PT1/8, stud M8x22, spring pins, and the cover gasket. Notice the note: inc. 3 ~14 – that means items 3 through 14 are included in the housing assembly. That kind of detail saves you from ordering a housing and then separately buying the pins and plugs that already come with it. A lot of aftermarket catalogs leave that out. Not this one.

Why Factory Part Numbers Matter

Aftermarket parts catalogs often guess at supersessions or group parts loosely. One wrong digit on a cylinder head bolt (129350-01230) and you get the wrong thread pitch. The OEM Yanmar catalog lists each part with its original nine-digit number and the quantity per assembly. For example, the CYL. HEAD BOLT on page 2 calls for 3 per engine, while the CYL. HEAD NUT calls for 2. That’s the kind of precision you need when you’re ordering for a customer’s machine. The Ammann Yanmar B12 B17 Parts Catalog covers a different family, but the same philosophy applies – if you’re working on the 3T75H line, stick with this one.

3 Reasons to Choose OEM Documentation

1. Correct part numbers. Every component from the plug 30 (121450-01990) to the oil sump gasket (121575-01750) is factory-verified.
2. Exploded diagrams. Figure 1 on page 3 shows the cylinder block, main bearing, and all associated hardware in a single view. You see how the parallel pin 8×20 (22312-080200) fits relative to the O-ring. That’s worth more than a thousand words.
3. OEM vs aftermarket reliability. Aftermarket catalogs may use generic drawings or skip the shim set and non-asbestos gasket options. The factory catalog gives you both choices – part number 121575-01750 (asbestos) and 121575-01751 (non-asbestos). No guessing.

If you’re working on construction equipment, you know that downtime costs money. The Yanmar YB271, B27 1994 Parts Catalog – OEM Factory Specs is another resource for smaller vertical engines, but for the 3T75H-LTBS and 3T75H, this is the one you want open on the bench.

Does This Catalog Cover Torque Specs or Service Procedures?

Straight answer: no. This is a Parts Catalog, not a service manual. You won’t find torque values, adjustment specs, or repair sequences here. What you will find is every bolt, gasket, bearing, plug, and stud listed with its factory part number. For a full rebuild, you still need the service manual. But anyone who tries to order parts without this catalog is working blind. The Yanmar YB301 YB351 1991 Parts Catalog – 248 Pages OEM covers another series, but the principle holds – OEM parts data is the only data you trust.

Who Needs This 64-Page Catalog?

DIY mechanics pulling a 3T75H out of a compact excavator. Home garage enthusiasts rebuilding a generator engine. Shops that bill by the hour and can’t afford a misordered part. Even if you’ve rebuilt a dozen Yanmars, new gasket materials change – the non-asbestos option on some parts (marked EB0523 or EB0489) tells you the supersession history. The automotive industry has moved away from asbestos, and this catalog reflects that. Automotive Industry Overview doesn’t teach you part numbers, but it explains why gasket materials evolve.

FAQ

Does this catalog include wiring diagrams?

No. Wiring diagrams aren’t in a parts catalog. You need the service manual for electrical schematics.

Can I use this to order parts for a 3T75H non-LTBS version?

Yes. The catalog covers both the 3T75H-LTBS and the base 3T75H. The PC code for the LTBS is Y00B4141; the base model shares most engine internals. Check the block assembly number on page 2 to confirm compatibility.

How do I read the exploded diagram on page 3?

Each numbered callout corresponds to the item list on page 2. The numbers are sequential – item 1 is the block assy, item 14 is the main bearing. The figure includes a note “inc. 3 ~14” meaning items 3 through 14 are subcomponents of the main assembly. Use a tablet or print the page; the scan is clear enough to see the spring pin locations.

What’s the difference between part 121575-01750 and 121575-01751?

One is an asbestos gasket (01750), the other is non-asbestos (01751). The non-asbestos version is marked “(NON-ASB.)” and was introduced as a revision. If you’re rebuilding a newer engine or want to avoid asbestos, order 01751. Both are listed with the same quantity and fitment.

Access the Factory Manual. Stop pulling parts off a crossed-out aftermarket list. This 64-page PDF gives you the exact numbers Yanmar stamped on the crate. Open it, find your part, and order with confidence that the bolt will thread. That’s the difference between a job done right and a return trip to the dealer.