In coordination with National Car Care Month, today the Bell Performance Blog talks about engine coolant. It's something often forgotten about until something goes wrong. Mechanics in Florida will tell you it might be the number one problem area they see with broken down vehicles - neglected coolant system service.
Your vehicle owner's manual specifies changing the engine coolant at certain intervals. Here's what happens when you don't get coolant system service at the recommended intervals.
When the engine coolant breaks down due to age and neglect, it produces acids. This acidic environment leads to the coolant becoming electrically charged. In order to have an electrical charge present in any system, you must have two different metals present - which you do have with the radiator (either copper or aluminum) and the iron engine block. When the engine coolant becomes acidified, there is an electrical charge built up that will need to follow a path to the ground somewhere.
In a car engine, this electrical charge does things like corroding the impellers off the water pump, corroding the passageways in the radiator, causing leaks, or corroding freeze plugs until they start to leak. This problem is more common in warm climates where cooling systems are ignored (like Bell's home state of Florida). In northern climates, most people are flushing and replacing antifreeze every year so they have very few problems with this.
Antifreeze Leaks in Engine
Antifreeze leaking into the engine oil will damage or destroy an engine. This is similar to putting sugar in the oil which will build up on engine bearings and block normal lubrication. Engine surfaces become scored and the engine will seize up, destroying the engine.
You can usually tell if you have water or coolant in the oil when you check the oil and spot a white foam on the dipstick. When this is noted, it is critical that repairs must be made quickly to stop this before damage results. Usually, coolant leaks are most commonly found in cylinder heads that were either cracked or warped from overheating. Modern engines with aluminum cylinder heads can be warped or damaged from even a one-time heating problem. When the engine gives signs of overheating, it is therefore critical for a driver to shut the vehicle down the minute a coolant temperature light comes on. Older engines with cast iron cylinder heads did not have this problem and could be overheated over and over without any negative effects on the engine.
This post was published on April 16, 2012 and was updated on August 2, 2022.