lawn boy mower quit in the middle of mowing last week .

[jackson55]

replaced spark plug started first pull. this week did same thing half way through lawn seems like it runs fine until it warms up a little

 

[Vervepipes]

We'll need more info, like what engine is on there.

 

[Rivets]

Sound like your coil is opening or shorting when it gets hot. Next time it happens, check for spark. If you have no spark, time to replace the coil.