Engine running despite the state of the SU

[Michael D]

you might want to read my post and. the replies thereto in the topic 'what have you done with your Austin seven today' as 1.25. inch SU carburetor running issues are being discussed there too. Including spring, damper, needle and settings. Methinks you've done wisely to blank off the hole that was meant for the advance vacuum line as that hole will have messed up your mixture by drawing in false air. Your plugs having been black is testimonial to a too rich mixture (although others may called it plug fowling by oil...) I like mine coffee brown but we're still tinkering (and probably fit a Ricardo head) so I cannot yet comment further.. but my 1.25 SU is on a blue spring and a No 6 needle (which at this moment may be a bit rich) and I'm happy to report it usually starts at first attempt with a bit of choke for starting only (but then again it is / was not in a cold and damp lockup )