Hi Gizmo,
Yes the first 3 are rotomo 2s. Tin wheel mid run,And two plastic wheel models. The last being in the last 1,000 rotomo 2s Built.
Model 4 180,322 appears accurate in serial and possibly still would retain some of the automatic parts this late on,But it is Well out of the Automatic Range. Remember Model 4 Std mowers ran beside the model 5 Special right up into the 300,000 serial run,but any left over parts were depleted well and truly by the end of the Run,and more likely before the 200,000 serial.
The Model 4 shown in the Image is in fact running a Normal serial sequence for A Very Late Model 5 Series 2,But more likely a Model 5 Series 3.....The Serial should read ICAA 21258.
This has clearly had an engine change and is the incorrect Serial No for a Model 4 Of any type. My interest though is in the rest of your mower. Does it have any of the wear indicators of it once being an Automatic?. A full Image may tell a little more.
But Ultimately Im looking for The serial sequences That Ive posted on Model 4 Examples.
The 265497 Serial is Perfectly Accurate for a Mid to late Model 5 Series 1
Thankyou very much for your Imput Gizmo,im very appreciative of your contributions. And who knows your little IACC may well have began life as an Automatic