The Case IH CS 120 page covers more than 400 parts for this CS series tractor, sorted by group and including lighting, trailer couplings and electrics.
A battery that will not charge, a dead work lamp or a dash switch that only works when you press it twice: on the Case IH CS 120, those are typical jobs. This page lists more than 400 parts that fit the tractor, from GRANIT, Scharmüller, HELLA, ROCKINGER and Carraro among others.
For the charging circuit there are alternators in several versions, along with V-belts to drive them. The cab takes work lamps such as a HELLA corner light with flood beam. Push button and rocker switches on the dash develop poor contacts over the years, and you can replace them individually.
Tip: when you fit a new alternator, fit a new V-belt too and set the tension correctly. A glazed old belt slips on the new pulley, the alternator undercharges, and you end up hunting for a fault in the wrong place. Check the earth cable while you are at it.
Before replacing a switch, look at the plug behind it. Moisture and corrosion on the contacts cause the same symptoms as a failed switch. A little contact spray and a firmly seated plug sometimes solve it, and only if that fails does a new rocker switch go in.
Leaks at the feed pump are dealt with using the seals and O-rings made for that spot. There is a gasket for the water pump and sealing rings in various sizes. The linkage uses bushes for the lower link shaft, which develop play after many hours.
If the bonnet will not stay up, a new gas strut for the hood sorts it. Tractor seats include the air suspended Maximo Professional, and PROBOSS seats are available too. At the back of the CS 120 there are automatic drawbars and adapter plates to mount a coupling.
The type plate tells you exactly which model you have. After that, the number on the old part is your best guide, as alternators, switches and gaskets often carry a reference number. With an alternator, also compare the flange and mounting with the unit you are taking off.
The CS range has several other models, each with its own page. Smaller than the CS 120 are the Case IH CS 75 and the Case IH CS 78, followed by the CS 94 and the CS 110. Always order through the page for your own type. For everything else from the brand, go to Case IH parts.