Problem with silver-plated rotary switch on a Marantz 2325

Q: (18989)

I have been using DeoxIT D5 cleaner on my Marantz 2325 beast for years now. It typically needs to have every silver-plated rotary switch sprayed every 6 months or so. As this is a lot of opening and flipping upside-down and sideways, so opted for the G5 gold spray 142 ml fluid ($40 Canadian) to hopefully leave a film to keep oxygen off the contacts a week after air drying the D5 away. Unfortunately the results were as if no G5 treatment was done, and the intermittent issue showed itself again.

Is my best bet to shove a bit of lithium grease into the rotary contacts about a week after a DeoxIT D5 treatment? I know it should be plastic-safe and if little is used it should not gum up much in the future. I do need to leave a film to prevent additional oxidation.

I don’t turn the function knob and know the DC bias voltage is accelerating the oxidation. I need to coat it well so i can save a constant need to repair every half year. I am considering bypassing the rotary switches all together. The contacts really are correctly aligned, but Montreal is a very humid environment.

My findings from the G5 were that it was unable to leave a significant coating of anything really. I think it pretty much all evaporates leaving the environment to take over. If it were not for plastics in the assembly I would be able to choose things that film over long term. Alas, since the 60s plastics took the industry and they are easy to destroy.

I cannot imagine repeating a procedure twice per year for life. Manufacturers used to do a mixture of stuff that protected well for about ten years back in the 70s. Lithium grease may very well be part of the good original mixture in potentiometers and rotary switches and from what i was told an early version of D5 was part of the mixture.

Thanks for any suggestions,
Richard