May well have been toluene. It was often used as a cleaner in all sorts
of
areas, some as pedestrian as the T/R/S plugs on old lamp-signalling
telephone
switchboards. Unfortunately proved to be a carcinogen and was banned, but
it
WAS used to clean a myriad of hardware in a myriad of situations.

It might have been carbon tet (tetracloride or however it is spelled). I
think it was taken off the market because of either liver or kidney failure
if the user had been drinking .