Kingbilly68
ArboristSite Lurker
The main concerns for a saw this old are the deteriorated condition of all of the seals, hoses, and other rubber parts. If you can't find any obvious oiler issues the pump mat be full of sawdust debris which will limmit the stroke and hence the output. I am pretty sure that this one can be disassembled and cleaned.
I used it some today and it oiled just fine. I did turn the oiler all the way up before I started.