Hi All, New to the forum. I just bought a used Simplicity L12.5, 38" deck. Runs beautifully, cuts perfect. But the battery continues to discharge. The guy who sold it to me said the battery was only a year old. It went dead a few days after I bought it. I figured he was not telling the truth so I bought a new battery. A couple days after installation this battery went dead. I can charge the battery and it will start for a couple days but again drains. Any ideas?