Touring the North West Coast of Scotland in two Austin Sevens, as a family

[Stuart Giles]

Ruairidh, Your holiday is certainly a real family adventure, and from the photos you've posted the scenery is really stunning. But are you sure you don't have a heat range, rather than a mixture issue with the spark plugs. if a sparking plug is too soft/hot it will always indicate a weak mixture even when the motor is running really rich as any normal deposits simply burn off the overheated spark plug. I have experienced this, but fortunately it was with a motor on the dyno, so it was more obvious what the actual issue was.