#1152<\/strong><\/p>\n For sale is an original Bosch vacuum advance unit 1 237 121 903 from old stock (NOS \u2013 New Old Stock)<\/strong>.<\/p>\n This vacuum advance unit is an unused original spare part from earlier Bosch production.<\/p>\n The vacuum advance unit is intended, among others, for the Bosch ignition distributor 0 231 309 001<\/strong>, which is used in various classic Mercedes-Benz vehicles with the M110 six-cylinder engine and carburetor.<\/p>\n Original Bosch vacuum advance units are particularly interesting for the professional rebuild and authentic restoration of classic ignition systems and classic cars.<\/p>\n The vacuum advance unit is part of the ignition timing adjustment and enables a vacuum-dependent adjustment of the ignition timing. The adjustment mechanism in the ignition distributor is actuated via the applied vacuum.<\/p>\n A correctly functioning vacuum advance is important for maintaining the ignition curve specified by the manufacturer.<\/p>\n Mercedes-Benz 280 \/ 280 C (W114)<\/strong><\/p>\n Mercedes-Benz 280 S (W116)<\/strong><\/p>\n Mercedes-Benz 280 (W123)<\/strong><\/p>\n Mercedes-Benz 280 C (C123)<\/strong><\/p>\n Important:<\/strong> The specified years of construction refer to the respective vehicle versions. The vacuum advance unit 1 237 121 903 was not used throughout the entire production period of all mentioned models. For some versions, use is documented until October 1977.<\/p>\n Therefore, please check the number of the installed Bosch ignition distributor and the part number of the existing vacuum advance unit before purchasing.<\/p>\n NOS stands for New Old Stock<\/em> and refers to unused original spare parts from earlier production.<\/p>\n Especially for the authentic restoration of historical ignition systems, original Bosch spare parts from older stock are particularly interesting.<\/p>\n Important note on item condition:<\/strong><\/p>\n Due to age and in some cases decades of storage, both the original packaging, if present, and the item itself may show signs of storage and aging. These include, for example, dust, light scratches, discoloration, or superficial signs of corrosion.<\/p>\n Please note the product images and the information on the respective item condition.<\/p>\n Before purchasing, please compare the Bosch part number 1 237 121 903<\/strong> or the Mercedes-Benz cross-reference number A 000 158 25 18<\/strong> with your existing component.<\/p>\n Vacuum advance units of different Bosch ignition distributors can differ in terms of their mounting, adjustment characteristics, and vacuum curve. A visually similar version is therefore not necessarily interchangeable.<\/p>\n If you have any questions regarding compatibility or the item, we will be happy to assist you.<\/p>\nProduct Details<\/h3>\n
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NOS \u2013 Original spare part from old stock<\/h3>\n
Fitment and Application<\/h3>\n