Most motor oils only provide minimal protection against damaging engine rust and corrosion. The effects of rust and corrosion are easy to see on the exterior of vehicles and equipment. However, they can also form on the inside of your engine if you’re not using a properly formulated motor oil. The problem is especially problematic in engines used in applications that sit idle for extended periods, including the following. Boats Motorcycles Lawnmowers Classic cars Snowblowers Despite what most people assume, motor oils have no natural ability to protect against rust or corrosion. Instead, special rust and corrosion inhibitors must be added to the formulation to provide the required protection, and some oils simply don’t contain the correct additives in the correct concentration. Idleness equals no protection During engine operation, a layer of oil coats engine parts and the crankcase walls. The lubricant film protects against rust and c...