I have a 17 HP Briggs & Stratton on a Murray riding mower. It starts and runs fine until it gets hot and I shut it off. It will not restart until it cools.

Your cooling system is clogged. Clean out any grass from around the crankshaft, exhaust, underside. If the problem keeps happening remove the air cleaner and clean that. Remove your housing and rewind assembly, clean out cooling fins of any debris. You must live in a dry area or cut dry grass. You basically have to take your machine apart and clean out the debris. If it still keeps happening then your engine may be going.

The coil could be overheating, clean the area under and around the blower housing.