Description

Yanmar 3TNA72L-UBA, 3TNA72L-UBB Parts Catalog – OEM Factory Specs for Two Engine Variants

Ordering the wrong part because some aftermarket catalog listed a generic number is a waste of a Saturday and your wallet. I’ve seen too many DIY guys bolt on a part that doesn’t fit, then blame the machine. If you’re working on a Yanmar 3TNA72L-UBA, 3TNA72L-UBB Parts Catalog – that’s the actual factory document that tells you exactly which plug, bushing, or bolt goes where. No guesswork, no returns. This is a 17-page parts catalog from Yanmar, not a reprint. It’s the original file with the original part numbers, production level codes, and cross-reference columns for the -UBA and -UBB engine models.

Yanmar 3TNA72L-UBA, 3TNA72L-UBB Parts Catalog: What You Get

This catalog is built around exploded diagrams and part lists. Each figure – like Fig.1 Cylinder Block, Fig.2 Gear Housing, Fig.3 Flywheel Housing & Oil Sump – gives you the reference number, part number, description, and quantity for both engine variants. You see columns labeled (A) for 3TNA72L-UBA and (B) for 3TNA72L-UBB. If a part is common, both columns show a 1. If it’s specific to one variant, only that column has a number. The remarks note undersize parts and parts sold as gasket sets. That level of detail saves you from buying a main bearing that doesn’t fit because the engine serial number range changed.

Cylinder Block Parts: What the Catalog Shows

Open to page 1 and you’re looking at Fig.1 Cylinder Block. Twenty-four lines of parts: block assembly, plugs, main bearings, thrust bearing, camshaft bush, cylinder head bolts, head gasket, and undersize main bearings (US=0.25). The part numbers are Yanmar OEM – 719610-01560 for the block, 119620-01200 for the cylinder head bolt. Each bolt is listed with its size, plating spec, and quantity. If you’re rebuilding and need to know which plug goes where (PT1/4, PT1/8, plug 45, plug 12, plug 30), this catalog gives you the locations per variant. That’s not something a generic parts list will do.

Does This Parts Catalog Include Torque Specs?

No. This is a parts catalog, not a service manual. It lists the parts and their OEM part numbers. You need a separate service manual for torque values, clearances, and assembly procedures. But here’s why it matters: when you’re ordering parts for that rebuild, you need the correct OEM numbers to match the service manual specs. For example, the main bearings are listed with an undersize option – 719620-02870 for US=0.25. If you order standard bearings by mistake, your oil clearance will be off. The catalog keeps you from making that mistake.

3TNA72L-UBA vs 3TNA72L-UBB: Identifying Differences

Look at Fig.1, ref 10-1 – the thrust bearing. For (A) 3TNA72L-UBA it’s listed “FROM 1ST”, for (B) 3TNA72L-UBB also “FROM 1ST”. But the part numbers are different. The catalog shows which build revision each applies to. Same for bushings and seals. If you’re swapping a used engine or splitting a block, you need to know if your engine is the -UBA or -UBB variant. The serial number or engine tag tells you. Once you know, this catalog gives you the correct part numbers straight from Yanmar’s production data.

Gear Housing and Oil Sump: Matching OEM Parts

Fig.2 Gear Housing covers the housing assembly, studs, spring pins, cover, oil seal, shim pack, and bolts. The oil seal (HTC456208) and O-rings are listed with their sizes. Fig.3 Flywheel Housing & Oil Sump includes the lubrication oil sump assembly, drain plug M22 with seal washer (22S), spacer, and all bolts. Note the parallel pin 6×1 and joint PT1/4. Every bolt is specified – M6x12, M6x16, M6x30, M6x45, M6x60, M6x80 – with plating codes. If you’re replacing an oil pan gasket, you need the correct sump assembly number (719631-01540) and the gasket set that includes it. That’s on page 3.

Using the 17-Page Catalog on the Bench

Toss this PDF on a tablet or print the pages you need. The exploded views are clear enough to identify parts without disassembling everything first. The “Remarks” column warns you about undersize parts and gasket set availability. For instance, the cylinder head gasket (119620-01343) is also sold in a gasket set (Fig.16, ref no.2). That saves you from buying individual gaskets separately. Cross-reference the part numbers with your existing engine to confirm. Don’t trust aftermarket part number lookups – they map to the wrong supersession half the time. Use the OEM numbers from this catalog to order from any dealer that stocks Yanmar industrial parts.

If you work on construction equipment, you know the difference between a factory part and a box-store substitute. The Ammann Yanmar B12 B17 Parts Catalog covers similar engines. For a matched pair of manuals, check the Yanmar YB271, B27 1994 Parts Catalog – OEM Factory Specs and the Yanmar YB301 YB351 1991 Parts Catalog – 248 Pages OEM. The automotive industry itself relies on OEM documentation for proper repairs; see Automotive Industry Overview for context. And if you want a broader look at why spec accuracy matters, Automotive Industry Overview covers the standards.

Access the Factory Manual. This is the only document that gives you Yanmar’s own part numbers for the 3TNA72L-UBA and 3TNA72L-UBB engines. No third-party translation, no outdated supersessions. Seventeen pages of factory data you can use today.

Frequently Asked Questions

Can I use this parts catalog to order parts for a different Yanmar engine model?

No. This catalog is specific to the 3TNA72L-UBA and 3TNA72L-UBB. Part numbers do not cross to other TNA series engines without verification.

Does the catalog include torque specifications for cylinder head bolts or main bearings?

This is a parts catalog, not a service manual. It lists part numbers and quantities only. For torque specs, you need the Yanmar service manual for the 3TNA72L engine. However, without the correct part numbers from this catalog, even the best torque wrench won’t help if you install the wrong bearing or gasket. The catalog ensures you order the correct components before you torque anything.