Tecumseh brand compressor is the cast iron one.
The less common York, was cast aluminum.
Believe you'll find that the dealer installed and in general service replacements were the aluminum versions. Might be due to the fact they were not going to rust on the shelves add weighed allot less for handling and shipping purposes
As "krelboyne" wrote the aluminum pumps are referred to as York pumps which is somewhat odd since the main cases are cast with Lester the supplier and were supplied (well at least some of the time) by Borg Warner at least 67-68 but again there were, most of the time, over the counter units
Thanks for the info, that will get me started on collecting the parts.
Were they dated?? Could I get one from a later year- car line, and still be correct??
Unless you have one of the rivet or bolt on labels from your application - no other applications will have different part/engineering numbers and dates if your going that far.
Will leave the dating question "krelboyne" since I know he's been looking at these details this last week