You've confirmed my suspicions ! I'll check the oil again now cold and see what colour it is! I'm thinking of using Valvoline 20/50 racing oil having had great success with that previously unless someone has other recommendations? Also anyone know the capacity save me looking it up? Thanks all!
1969 4/4 1995 plus 8 2002 Aero S1 2013 M3W 2014 Plus 8