I have Scotts riding Lawnmower that I'm having problems getting to crank, M/N is GX25463013793, the engine is a 25 HP Briggs & Stratton. I have replaced the Battery already ,the problem is that when I turn the key the starter will engage the flywheel, it will turn a quarter to a half a stroke then stop and you will start to hear a high pitch sound coming from the solenoid, I have also jump the starter directly from the battery, same thing happens, I pulled both plugs and I can get the starter to turn the engine over no problem, put in one plug and the starter will not turn the engine. Is it time to get a new Starter?

GX254

YEP you are correct. I rebuild an 18 horse b&S which before the starter that was on it would turn over. After I rebuild the compression was tighter and the old one wouldn't do it. Replace starter.