An Ounce Of Prevention – The Importance Of Antifreeze/Coolant Service – Take a look at these photos, notice the dark areas of pitting and corrosion on the engine block? Nowhere is this more frequent than on engines using an aluminum cylinder head, and cast iron block…like most modern cars.
This Mercedes E320 engine, car presented with a large external oil leak from the head gasket area. Removal of the cylinder head, a extensive and expensive repair, showed one of the prime causes for leakage, engine block pitting. The sad fact is is that such damage is easily preventable, by a simple service that usually costs less than $100, a proper and complete engine coolant flush.
One failure mode associated with dirty coolant is known as electrolysis. Electrolysis occurs when stray electrical current routes itself through the engine coolant. The electricity is attempting to find the shortest path, and impurities in the coolant often generate a path of least resistance that the electricity travels across. Electrolysis can destroy your engine quickly. Values greater than about a tenth of a volt can start reactions between the coolant and the metal in your engine. In particular, electrolysis affects primarily aluminum engine components, resulting in pitting and scarring of the aluminum surface. This eating away of the metal can cause coolant system leaks, and in particular, radiator leaks around aluminum welds. Cast-iron components are also vulnerable, but typically the aluminum metal parts fail first. So change that coolant!
Sounds simple, right? Yet one of the most neglected task on many newer cars is the maintenance of the cooling system. Today’s high tech cars often come with so-called “lifetime” coolant, promising extremely extended coolant intervals. The problem is, these intervals come at a cost, expensive engine damage down the road. In general, it’s recommended that you flush and clean out your cooling system once every 36 months, or approximately every three years.
The best way to protect your engine, and ultimately, your wallet or pocketbook, is to make certain your car’s coolant is flushed at least every 3 years, shorter if it is a vehicle that sits for an extended time. Fall time is ideal to ask your service facility about your vehicle’s coolant. An ounce of prevention is always worth a pound of care, our goal is always to prevent, rather than just repair problems.