The 123 ignition systems have a universal housing, when mounted in our air-cooled Volkswagens, a gap is left between the ignition housing and the mounting bracket. To fill this gap, this aluminum spacer ring can be selected as an additional option with the 123 distributor.
This ring is not only intended for a neat finish, it also makes mounting much easier and also safer. If the distributor is equipped with the filler ring, the distributor will undoubtedly be placed in the exact position in the housing. If the filler ring is missing, the distributor may be placed too deep or too shallow in the crankcase, which may damage the distributor and/or the crankcase.
We recommend that you purchase this ring along with your new 123 ignition. Even if you have had this distributor for years, we still recommend that you install this spacer ring. If you don't do it for the correct way of mounting, then it's for appearance so you don't have to explain every time you show the engine compartment that your distributor is mounted the correct way.
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