my 16v 190e had a radiator cap with the #120 on it, after i got it back from the mechanic he had replaced it with a #100 cap.(is this okay or should it only have a #120 cap on it)

The 100 cap is = to 1bar of pressure. long ago Mercedes updated them all to the 140 cap. IE 1.4 bar . The 100 is a old stock and should be updated.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
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