I guess he needs to know what kind of oil he needs also

Oil is mixed with gas for 2 cycle engines only, not 4 cycle engines.
http://odref.com/pdf/Ryobi/
Try this site for owners manual. Hope this helps.

You must be confused a 4 cycle motor doesn't need a mix because the oil and fuel is seperate like a lawn mower or car. You must be needing a 2 cycle mix amount for his weedeater I would use a 32:1 mix which is 4 ounces of 2 stroke oil to 1 gallon of gas. OR he can use a 24:1 mix which is 5 ounces of 2 stroke oil to 1 gallon of gas. both are good mixes for a weedeater.

4-cycle engines don't use oil in gas. Do you mean a 2-cycle engine? If so, 32 parts gasoline to 1 part oil is a good rule of thumb for weed whacker 2-cycle engines.

The oil is a "special blend" for 2-cycle engines which can be purchased at hardware stores.

Charlie

You shouldn't need to mix oil with gas on a four cycle engine. this is for two strokes.