It's a long time since I stripped down an SU carb but you should be able to tell visually if the shaft is worn.
I can't remember if rubber or neoprene seals were used but there's the possibility that these may be leaking given their potential age. Have you tried running the car and dropping some oil over the spindle end to seal out the vacumn leak?
Have you thought about contacting Burlen Services, Shaftesbury as they manufacture SU carbs, stock spares and will rebuild if required.
Last edited by Cheshire_David; 20/05/16 12:17 PM.
