Want to clean the air cleaner on my '51 Ford F1 and put in some fresh oil. I can't find the type of oil to use or how much to add. Any suggestions?

 

Operator's manual should have this information.

Usually or maybe typically it will be spec'd as straight 50 or maybe 30 wt. oil in summer and lighter weight for winter. Probably most people just run whatever oil it is they are putting in the crankcase. Usually a pint (16 fl. oz) afaik, a lot of times there will be a fill line or arrows or something.

 

Any reasonable kind of engine oil, per the manual