I also have an Elliot 2G, I bought it around 20 years ago and it also has always had a large amount of backlash when it the high range. I have always done as Andrew mentioned, and just wind the chuck backwards before switching on to take up the slop to avoid the sharp loud clunk.
When the low range backgear is engaged there is only a small amount of backlash.
Many years ago I did remove the gearbox cover and couldn't find any wear or broken parts, so I think it may be just the way they are made.
A few years ago I bought a three phase motor and VFD for it, and these can be programmed to give a very gentle startup and acceleration up to speed. So, as well as other benefits, that should remove the need to wind the chuck back before starting, once I fanaly get it fitted.
Edited By Lathejack on 07/01/2017 18:16:55
Edited By Lathejack on 07/01/2017 18:23:08