When converting from R12 to R134 is it necessary to flush the system and if so what should be used, also is it necessary to change the seals ?

I have an 82 733I.

Yea, you definately have to flush the system first, and I think you'r right the seals will need changing, the original seals can't handle the new gas.
I recomend you get the pro's to sort it out.

Rossco
1996 E36 320i
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