Hey Paul:)
The whole run of model 4 Autos had all but ended at the release of the model 3. This carb was well in service already. While the 2a pulley was a carry over and correct for early model 3, Im unaware of the earlier circlip carby being used this late. Remember there are often discrepencies in early Victa models especially in transition stages. So there is a minute possiblity the last 2a mowers may have had the newer latch style 3f, but highly unlikely the model 3 got the circlip style (but I wont discount 100% that a few wernt used if original examples can be shown). Also Approx 20,000 mowers had been released since the new carbs intro prior to the Model 3 release.
