Well I think I`ve sorted this out. Used a syringe with a large blunt needle (from an inkjet refill kit) to remove some of the original "oil" . It was very thin and had a smell of a spirit not a plane oil. Would`nt mix with glycerine or light oil the just went cloudy so "sin of sins" I tried surgical spirit as this had a similar smell and feel. Mixed a treat so filled the syringe and carefully refilled the compass. Well its sat for a few days now and seems fine, no bubble anymore and hasn't affected any makings on the disc. For anyone interested its 95% industrial meths. I don't know what the true chemical names is plus a bit of caster oil.
Chris.