Complex sentence: To head off problems and attempt to save money they opted to purchase outsourced engines to retrofit on the Gravely Tractor, and stopped producing the Gravely built engine which was simple and efficient.
Split into simpler sentences: To head off further problems and attempt to save money, they opted to purchase outsourced engines to retrofit on the Gravely tractor. This stopped the production of the Gravely built engine which was simple and efficient.