Dismantling and lubing Jupiter 9
Hello I have a very nice example of Jupiter 9 in Kiev-Contax mount, but its focus ring is very stiff.
It is so stiff that when I try to turn it, at some point the force I need to aply to make it turning makes the locus lever on the lens jumping and the lens itself turns out of the mount.
I dismantled the rear part of the lens and arrived to the rear helix, and found that it is mostly dry, but remains some quantity of a very smelling, grey grease. I would like to remove that grease and relube the lens with a better lubricant.
Please guys guide me about what lubricant use, what special cares I must take (I was thinking using lighter fluid to remove the old grease, but I am afraid that the lighter fluid enter inside the lens through the joints and ruin the lens). Optically is an excellent example.