Those B&S 23s are jetted lean, mine is not only hard to start in the winter (in Texas of all places) and runs very poorly in hot weather. In the heat it snaps and pops and runs like an 18hp does in...Noel Woods 01-30-2015, 07:58 PM
You may also check for corrosion at the cdi plugs (black box), they are hard to play with.
Check plugs first, easy, simple, common and more likely. More common with other brands, but happens.