Ortofon RMG309 fix
Simple fix for sagging counterweight on Ortofon tonearms
When I acquired my RMG309 a nylon tie was wrapped to support the sagging counterweight due to a deteriorated rubber tube that decouples the counterweight from the rest of the tone arm assembly. Since I was restoring an SME 3009 that had the same problem I ordered an extra set of rubber decoupling tube which fits the Ortofon but was too soft to support the more massive counterweight. What is required is a harder type of rubber tubing available from an auto supply.
Fixing the problem is very simple. To disassemble, loosen set screw  to release the spring, set screw  to remove the counter weight and then carefully pull out the short aluminum tube . Remove all the deteriorated rubber inside the short aluminum tube  as well as on the other end towards the gimbal bearing tower . Using fine sandpaper sprayed with a burst of WD40 clean the short metal shaft  until it is smooth and shiny. This will later be force fit into the new rubber tube  which is a 1/4" OD and 1/8" ID rubber tubing approximately 1 3/8" long I found at a local auto supply for .75 cents a foot. I did not bother to crazy glue the rubber tubing since there was enough resistance in the fit.
This is how it looks after reassembly.