My secondary mower (only because of this problem) is a Husqvarna ZTR. It is powered by a 17.5 HP Briggs - Stratton Intek OHV engine. It has a tendency to break push rods. Is this a problem inherent with this engine? Is there something I can do to help prevent this? It's getting a little old replacing push rods towards the end of each mowing season! Oil is kept clean and filter changed. Thanks for any comments.