Hi James,
Great score,and im so happy...Your Happy! lols. I cant see the front of the base on the first mower,( or im blind,lols) The IAAA....But I agree with blumbly.
I would put the IAAA.... at the very late end of the model 5 run,VERY late series 2 possibly even series 3,I assume it has the flush front axle mounts?. It should have. Since it still has the edger groove and assuming its the original engine for this base,then yes VERY late model 5 series 2. (If its the series 1 base,then its incorrect). Also somewhere in the mid to late model 5 series 2 run,the number and letter stamping changed. Note the A" as an EG, is sharper and doesnt have its feet like the earlier stamping. This is how you tell the later engines,from the serial sequence,the stamping and the generally smoother cast crank cases.
The AC.... As Blumbly says,unfortunately is incorrect for this series 1 base. Going of lettering/stamping and sequence I would place this as an early to mid run model 5 series 2 engine. Should be Flush front axle mounts. For this mower id try to find an engine with the serial number between say 200,000 and 300,000 generally coded 5 on the lower. If your particular about originality
Enjoy your new toys James.!!!
