Description

Koehring 166 1974 Parts Catalog – Factory OEM Parts Reference

If you’re tracking down a part for a Koehring 166 that’s been sitting in a field or working a job site since the 1970s, you know the drill: guess the part number, order it, get the wrong piece, lose a day. I’ve been turning wrenches for 28 years, and I’ve seen more misordered parts than I’ve had hot meals. A factory OEM parts catalog cuts that crap out. This Koehring 166 1974 Parts Catalog is the real deal – 93 pages of original Koehring part numbers, group breakdowns, and serial-number-specific callouts. No aftermarket guesswork. No “universal” list that fits nothing. This is what the factory used to stock their own bins.

Crawler & Carbody: Where the Undercarriage Parts Live

Group 1 covers the crawler and carbody assembly. If your tracks are sloppy or the sprockets are worn, you’ll find the exact sprocket, idler, track roller, and chain part numbers here. The manual lists every serviceable part for every machine built of this model designation. That means not just the standard undercarriage, but also the optional variations that Koehring shipped from the factory. You need the serial number of your machine – printed on a plate near the operator’s cab – before you start flipping pages. Without it, you’re guessing.

Upper Structure, Turntable, Fuel Tank – Group 12 Coverage

Group 12 is where the fuel tank lives, along with the upper structure and turntable. If you’re chasing a fuel leak or replacing a worn turntable bearing, this section gives you the Koehring part numbers and the assembly relationships. The fuel tank itself is shown with its mounting brackets, filler neck, and sending unit – all listed with factory part numbers. The Fuel system is critical on these old machines; a misordered tank or sending unit means down time you don’t have. This catalog gets it right because it’s the same one the Koehring dealers used.

Engine Assemblies: Detroit Diesel and Cummins Options

Two engine options were available: Detroit Diesel and Cummins Diesel. Each has its own group (14 and 14A). The parts catalog breaks down every gasket, piston ring, valve, and injector part number for both engines. If you’re rebuilding an Engine on an old 166, this is where you find the correct part numbers – not a generic “fits all” aftermarket chart. Use it with the service manual for torque specs, but the parts catalog gets the numbers right. I’ve seen jobs go sideways because a rebuild kit had the wrong ring pack. Factory data eliminates that.

Hydraulic System and Swing System – Factory Group Numbers

Groups 2E (Swing System) and 2F (Hydraulic System) cover the pumps, motors, valves, and swing drive. The hydraulic system is the heart of an excavator, and misordering a control valve spool or a swing motor seal can cost you a week. The parts catalog shows exploded views with callouts that match the group block numbers. You’ll find the pump drive case in its own group as well. This is not a generic diagram – every part number ties back to Koehring’s own inventory system. For a machine like the 166, that’s worth its weight in bearings.

3 Reasons to Choose a 1974 Factory Parts Catalog

First, it lists parts for every serial number from 63100 up. Koehring made product improvements – you need the serial number to know which revision of a part fits your machine. Second, the numerical parts list at the front cross-references every part number to the page where it appears. You can verify if a part is still serviceable or if there’s an improved substitute. Third, it’s the original OEM document – not a reprint, not a scan of a scan. This is the litho-in-USA original, Part No. 12261-74. Aftermarket “replacement” catalogs often renumber parts or skip groups. Don’t risk it.

Does the Manual Cover the Electrical System?

Yes. Group 132 covers the electrical system – wiring, switches, gauges, and the starter. Group 133 includes the horn, wiper, floodlights, and accessories. If you’re chasing an electrical gremlin, the parts catalog won’t give you a wiring diagram (you need the service manual for that), but it will give you the exact part number for the switch or relay you need. Combine it with the OEM service manual for a complete repair picture. See Automotive Industry Overview for background on why factory documentation matters.

Get the Right Part Numbers with Serial Number Verification

Before you order any part, locate the serial number of your Koehring 166. The manual states it clearly: “KNOW THE SERIAL NUMBER OF YOUR MACHINE before searching for replacement parts.” The parts groups are organized by functional assembly, and a letter suffix (like 25A) indicates optional or variable parts. If you skip this step, you’ll end up with the wrong bushings or seals. I’ve seen it happen too many times. Use the numerical parts list at the front to cross-check part numbers against the page references. That’s how the factory kept their parts department straight.

Related manuals you might need: Koehring T-S44, 644 1974 Parts Catalog – Factory OEM Parts Reference, Koehring S-155 1977 Parts Catalog – Factory OEM Parts Reference, Koehring 366 Hydraulic Hoe Parts Catalog – OEM Factory Specs. Also check out Automotive Industry Overview for more on the value of OEM documentation.

What serial numbers does this parts catalog cover?

Serial number 63100 and up. Check your machine’s plate before ordering.

Does this manual include fuel system part numbers?

Yes. Group 12 covers the upper structure, turntable, and fuel tank. The fuel tank, brackets, filler neck, and sending unit are all listed with Koehring part numbers. If you need fuel lines or filters, those are in the engine groups (14 or 14A) depending on your engine option. Don’t order a replacement tank without cross-referencing the group number first – the manual includes the exact part numbers for your serial number range.

Is this a reprint or a third-party copy?

This is an original OEM factory catalog – litho in USA, Part No. 12261-74. No reprint, no aftermarket compilation. The pages are the same as what Koehring dealers used in 1974.

How many pages is it and what format?

93 pages. Digital access in PDF format. Full parts groups from crawler to attachment options.

If you’re maintaining a Koehring 166, stop chasing parts based on memory or aftermarket lists. Access the Factory Manual – this OEM parts catalog will get you the right part number the first time. No guesswork, no returns. That’s how professionals work.