The Ryobi 137R is an electric powered string trimmer that uses nylon cutting line to trim weeds and grass in the yard or landscape around a home. A .080-inch diameter nylon trimmer line is wound onto the spool of the trimmer head for use. Unlike some other string trimmer models, the cutting line spool on the Ryobi 137R doesn't need to be removed for line installation.
Disconnect the extension cord from the Ryobi 137R trimmer to prevent accidental starting.
Hold the outer spool of the trimmer head on the Ryobi trimmer and turn the inner spool so that arrow on the outer and inner spools line up.
Pull old line from the spool and discard of properly. Cut two 10-foot lengths of .080-inch diameter nylon trimmer line from a filler spool with scissors.
Insert the end of one 10-foot length of trimmer line into the hole on one side of the outer spool. Push the line until it emerges through the inner spool. Turn the end of the line extending through the inner spool and insert it into the locking hole.
Install a second 10-foot length of .080-inch diameter line into the hole on the opposite side of the outer spool. Insert the end of the line extending through the inner spool into the locking hole. Pull gently on both lines extending from the outer spool to remove any slack.
Hold the outer spool and turn the inner spool counter clockwise or to the left to wind the line onto the inner spool. Leave 4 inches of line extending from the outer spool for operation.