spark plug is good but when its plug in to coil on spark
.025 inch per the manual.
I just looked that up for mine. I found this chart: http://www.psep.biz/store/ryobi_trimmer_spark_plugs.htm it depends on which trimmer you have
To replace the line on a Ryobi RY15523A trimmer, follow these steps: Turn off the trimmer and disconnect the spark plug wire. Remove the spool from the trimmer head. Cut a length of replacement trimmer line. Insert the line into the trimmer head following the arrows for the correct direction. Wind the line evenly and tightly onto the spool. Reassemble the spool onto the trimmer head. Reconnect the spark plug wire and test the trimmer.
To change the string on your Ryobi weed trimmer, follow these steps: Turn off the trimmer and disconnect the spark plug wire for safety. Remove the spool housing by pressing the tabs on the sides and pulling it off. Take out the old string spool and replace it with a new one. Feed the new string through the holes in the spool and secure the ends. Place the spool back into the housing and reattach it to the trimmer. Reconnect the spark plug wire and test the trimmer to ensure the string is working properly.
To replace the string on your Ryobi string trimmer, first turn off the trimmer and disconnect the spark plug. Then, remove the spool housing and take out the old string. Cut a new piece of string to the appropriate length and feed it through the trimmer head. Wind the string in the direction indicated on the spool and secure the ends. Finally, reassemble the trimmer and test it before use.
Champion CJ8 spark plug is for the crsftsman 3.0 edger/trimmer
Champion RDZ19H
To perform a Ryobi trimmer string replacement, first turn off the trimmer and disconnect the spark plug. Remove the spool cover and take out the old string spool. Cut a new piece of trimmer line to the appropriate length and insert it into the spool. Wind the new line evenly onto the spool in the direction indicated on the spool. Reassemble the trimmer and test the new string before use.
.023"
This part number is for a Champion RDJ7Y spark plug. Set gap at 0.025" I bought a replacement plug, DJ7Y, at Home Depot on 10/6/13 for $2.38 + tax. The DJ7Y replaces the RDJ7Y. This plug is used for other tools such as my Ryobi trimmer and McCulloch chain saw.
EZ start 5847 or DJ8J