Starter ropes on lawn mowers frequently break. You constantly yank the cord. It gets wet in the rain and baked in the sun. And one day, it breaks off in your hand. You could take the mower to the dealership where they will replace the cord for a small fee. But then there's the problem of getting it there, especially if you do not have a truck. Luckily it is easy to repair a starter rope yourself. It will only take a few minutes and as you will likely have to do it again, the skill will come in handy.
Buy starter rope cord.
Open the top cover of the lawn mower by removing the bolts.
Remove the starter pulley's housing (if there is one) by removing the bolts.
Remove the old rope (you may have to remove the starter pulley to accomplish this) from the starter pulley.
Cut a section off the new starter rope spool that is just as long as the original rope.
Attach the new rope to the starter pulley by threading it through the hole in the starter pulley then tying a knot to keep it from slipping back through.
Wind the rope around the starter pulley twice on most models. Use the channel around the starter pulley as a guide. There should be just enough string to almost fill it.
Thread the free end of the starter rope through the hole in the starter pulley's casing.
Re-attach the pulley if you removed it and then replace the metal cover
Pull the cord a few times to make sure that the starter pulley is recoiling properly.
Attach the free end of the cord to the T-shaped handle. Thread it through the hole at the bottom of the "T" and through the top. Then secure it with a knot. On some models, the string is attached to the T-shaped handle through other means. Duplicate that attachment method if this is the case.