Avid SD7s won't tighten on the bosses

[pswann]

I am trying to install a brand new set of Avid Single Digit 7 v-brakes on the rear of my Surly 1x1. The bike is 2 years old and has had an SD7 on it before (I cannibalized it to build a Karate Monkey, now I'm rebuilding the 1x1 and using a new rear brake).

I slide the the arms onto the bosses, making sure the pin is in the center hole, and tighten to the specified torque using a torque wrench, but both arms are still loose on the bosses. They rattle around and slide up the bosses at least a millimeter.

I have lightly greased the bosses and the mounting bolt, am using the supplied washer and I just can't figure out why I can't get these things tight. I've tried adding another washer on top of the existig one and that doesn't do anything.

Any ideas would be appreciated.

 

[Born2bahick]

I slide the the arms onto the bosses, making sure the pin is in the center hole, and tighten to the specified torque using a torque wrench, but both arms are still loose on the bosses. They rattle around and slide up the bosses at least a millimeter.

Are the return spring arms tight or close to having some tension on them at this point? I have seen tektro V's that slide on the boss about 1 mm, but the tension from the return spring arm keeps them from rattleing or bouncing. The avids I have have no room on the boss's to slide like the tektros, however neither should rattle or bounce.