Small Engines (Lawn Mowers, etc.): mccllough chain saw, white lithium grease, wt oil

Question
I have an older chain saw, more than likely at least 30 years old. It's an all steal casing with a fuel capacity of about .5 gallons. It runs well but my problem is that I don't know where the oil goes for the blade? There is no resevoir for the oil, only fuel. However, there is a little screw on the bottom with a spring, it is a flat head screw.  When you put oil in it, the motor will not turn. If you could assist me in where the oil goes for the blades, I would very much appreciate it.  Thank you very much, Pete.

Answer
Pete,

  Your Chainsaw is what Landscapers call a Zipcutter used for cutting small limbs also because no oil for the bar resevior is present making this a fast use  saw.
the screw with the spring is merely a fuel to air ratio adjustment for engine performance.
Unfortunatly this saw requires you squeeze the Bar Oil onto the bar itself before Use.
Bar Oil is Basically 90Wt gear oil try this to keep the bar cooled
loosen the Chain and squeeze some White Lithium Grease into the chain guide channel all the way around the bar then add some 90 WT oil to the chain itself.
Normally the Bar oil resevoir is located next to your fuel tank or On the top of the saw itself.
Your older Model May not have the bar oil res on it meaning Its a Zipcutter