Serial number would normally be on a tag on the gas tank if that is present at all. otherwise I’m sure that there are part numbers cast into the cylinders or something, and these might have changed number over time so that could provide some definition. I think that tag on the gas tank is the only actual serial number though I may be wrong. The lower unit would provide more definition. Some have the solid rudder and some have the hollow rudder. The solid rudder motors have the water pump in the lower unit and look a little different from the later hollow rudder one if I am not mistaken. The rudder steering arms in the picture look like an older one before model C to me, but a model C is the only model I have ever owned. The flywheel and power head stayed very similar thought these years and the only big change was the lower unit and the gas tank shape if I am not mistaken. Also, the flywheel knob retracts on the model C, but I think it might not on the earlier models-or I am just making that part up in my head? To me, it looks like an earlier one but I could be wrong. What are you looking to do with it? If the lower unit is in OK shape you could probably get it running with a new gas tank and a carburator as well as a new timer and ignition system. Maybe best for parts and find a complete motor to fix?
"Outboards seem to multiply exponentially..........I find that for every finished project, there are two more waiting to be completed."
