cal44

I needed new wiper arms for my '86 911. So I ordered new from a Porsche parts supplier (not Pelican). Well they have sent me the arms but the hole seems a little large. When the arm is laying flat and is not bolted down it moves freely. The ribbing on the stud (part that sticks out from body)is there for a reason, to stick into the hole of the wiper arm and secure it. When I removed the factory wiper arms (origianl) I needed to raise the wiper arm at 90 degrees to get it off. When flat is was as though it was locked into place.
Does this make sense, my rambling? The new arms when flat move around if the bolt is not tightened. I thought the teeth digging into the wiper arm aided the bolt for strength. These guys claim the new arms superceed the old design. Any thoughts.

3.2SLANTNOSE

A couple of questions. Why were the arms needing to be replaced, damage or just cosmetic reasons? What is the part number for the arms that you received? 1976-1989 part numbers for left and right sides were
964 628 028 01-Left
964 628 028 02-Right