I know someone who has an old wheelhorse lawn tractor with a HH60 horizontal shaft. He was complaining about the engine losing power after 15 minutes, overheating, and spewing oil out the breather. It turned out he didnt have the governor linkages set right, and the governor gear actually split in half, so he was actually running it wide open non stop and he had no problems besides the oil spewing and overheating. But then again i know stock engines that have thrown rods under normal circumstances.