Hi Jonesy, yes there was a change in carby at the Model 4 Automatic Predicta which was the Victa model 5 carby then back to the 3f for the Standard, Special, and Model 6&9 Sheerline. Hoping this helps mate...
Please do not PM me asking for support. Please post your questions in the appropriate forums, as the replies it may receive may help all members, not just the individual member. Kindest Regards, Darryl