The exact horsepower of a 285 Massey Ferguson tractor varies depending on the year and type of engine installed in the tractor. Generally, 285 Massey Ferguson tractors are equipped with either a 3.152 liter or 4.236 liter diesel engine. The 3.152 liter engine is rated at 73 horsepower, while the 4.236 liter engine is rated at 89 horsepower.