I forgot to mention that the Tecumseh powerhead is air cooled, but the exhaust column is water cooled by an impeller. Do not run it out of water. Impellers can be purchased on ebay and i believe there are regular ones and tall ones depending on the model. You will have to compare yours to the ebay pictures.
The 217 part of model number is a Sears Source Code that identifies maker Eska.
Sears retailed products made by a variety of manufacturers and identified maker
by first three digits of model number. Source Code list available on internet
may be helpful or not as Sears products were sometimes unique or modified versions of makers own brand.
Louis