Description

Iseki SG173 Parts Catalog

If you own an Iseki SG173 lawn tractor, you already know that factory parts diagrams beat aftermarket exploded views every time. Aftermarket catalogs mix up part numbers, skip the interchange codes, and give you the wrong bolt length. Then you end up with a crate of parts you can’t return because the thread pitch is off. This Parts Catalog is the genuine Iseki document — 222 pages of factory-assigned numbers, interchange codes, and paint color references. No filler, no third-party rewriting.

I’ve torqued enough head bolts to know that one wrong part number can turn a two-hour job into a full day of re-ordering. That’s why I keep the factory catalog on the bench, not a photocopied aftermarket list. Automotive Industry Overview might tell you how assembly lines work, but this catalog tells you exactly which bolt goes where on an SG173.

Directions for Use: Understanding the Layout

Page 1 of the catalog lays out how to read the head paragraph. Every key part code, description, quantity, and illustration location is explained. The column labeled SPC uses symbols: * for standard parts, T for optional, R for replacement. If you skip that column, you’ll order a part that doesn’t fit your SG173 model variant. The catalog also lists area codes — E20 for Germany, E40 for UK & Oceania, E42M for Europe standardized model, E50 France, E50T Italy. Different markets got different parts, and the catalog separates them by serial number ranges.

7 Key Sections in the Parts Catalog

This document is organized by system groups — engine, transmission, steering, mower deck, electrical, chassis, and hydraulics. Each group breaks down into component illustrations with callout numbers. The part number, description, quantity, and interchange code (ITC) are given right next to the exploded view. You don’t need to flip between pages to find the alternator bolt — it’s all on the same spread. ISEKI SSM48 Parts Catalogue Directions For Use uses the same page structure, so if you work on multiple Iseki models, the learning curve is flat.

Color Codes and Paint Types

Page 3 lists the factory color codes for painted parts. Silver Mist (8E), Summer White (6G), Mirror Black (7F), Neo-Blue (4L). Each color has a spray-type code and drum code. If you need to repaint a hood or fender, you look up the color code from the parts catalog and order the exact Iseki-matched paint. That’s how you keep the tractor looking factory — not by guessing at a hardware store rattle can.

Why OEM Parts Catalogs Beat Aftermarket Lists

Aftermarket parts compilers often leave out the ITC (interchangeability) codes. ITC 1 means new part replaces old, ITC 2 means old part can still be used in place of new, ITC 3 means they are not interchangeable. Without those codes, you might buy a superseded part that doesn’t fit your SG173 serial number. The catalog also shows GRP codes — parts that can be replaced as a set (e.g., a bearing and seal sold together). Aftermarket printouts never include that level of granularity. ISEKI SSM48-M Parts Catalogue Directions for Use covers similar ground for the SSM48-M, but the SG173 catalog is specific to your lawn tractor’s frame and mower attachments.

Serial Numbers and Model Type Breakdown

Every component listing in this catalog references the serial number range of the SG173. The OCR excerpt shows two columns: QTY per unit and serial number range. For example, some parts are listed as “-229” (up to serial 229) or “230-” (serial 230 and after). If you have a later serial number, you get the updated part. That information is printed directly next to the part number — no separate bulletin needed. Iseki TS3110 Parts Catalog – Factory OEM Parts Breakdown also includes serial number splits, but the SG173 catalog covers the power steering and mower deck versions (U, 48, R, S).

What This Catalog Does NOT Cover

This is a parts catalog, not a service repair manual. It won’t tell you how to rebuild the hydrostatic transmission or adjust valve clearances. For that, you need the Iseki SG173 Service Manual. The parts catalog is meant to be used alongside the repair manual — you look up the part number, then refer to the service manual for the install procedure. If you need torque specs or bleeding procedures, grab the service manual. The parts catalog gives you the part, the service manual tells you how to put it on without breaking it.

For background on why factory documentation matters across the industry, see Automotive Industry Overview.

FAQ

Does this catalog cover the 48-inch side discharge mower deck?

Yes. The model type code “48” designates the side discharge mower with 48-inch cutting width. All option parts for that deck are listed in the catalog.

Can I use this catalog to order parts for an Iseki SG173 with rear discharge mower?

Yes. Model type code “R” identifies rear discharge mower variants. The catalog includes separate part listings for each mower type.

What is the difference between ITC 1 and ITC 2 in the interchange column?

ITC 1 means old part can be replaced by new part (backward compatible). ITC 2 means old part still fits in place of new part (forward compatible). ITC 3 means they are not interchangeable — you must use the correct serial number range to order.

This catalog has 222 pages, but I only see a few screenshots online. Is it the full PDF?

Yes, 222 pages is the complete factory parts catalog. What you see on free sites are often reprints missing the color code pages and ITC tables. The original PDF includes every section.

Access the Factory Manual now and stop guessing on part numbers. One wrong bolt can cost you a Saturday.