HOURS MAP

What Causes my Car to Overheat?

CC image Wikipedia.orgMost of the dials on a person’s dashboard are easy to understand and interpret.  Everyone knows what makes your speedometer increase and your fuel gauge decrease, but what about your car’s temperature gauge?  What causes the dial to creep up towards the big “H”?

There are three main reasons why a car might overheat.  They are:

  • Loss of coolant
  • Inability of the coolant system to get rid of excess heat
  • Excess heat in the engine

We’ll examine common problems that cause all three of these issues.

Loss of coolant

Coolant helps regulate the heat in your car.  If your coolant is empty, certain parts will begin to “run hot”.  If your car’s internal systems begin to overheat, it can cause serious and expensive damage.  Leaks in your water pump, radiator, hoses, gaskets or plugs can lead to the loss of engine coolant.  Another simple reason why your car may be leaking coolant is because your radiator rap is loose, which allows coolant to spill out.  These are usually the first places a mechanic will check to identify the problem with your heating system.

Inability of the coolant system to get rid of excess heat

If the coolant system is unable to flush out the heat produced by the engine, your car will begin to overheat.  This usually occurs because there is a clog in the cooling system.  Deposits in your cooling system can develop over time, so it’s important to make sure you get routine diagnostics tests.  A mechanic will attempt to de-clog the system by doing what is called a “reverse flush”.  If your system is extremely clogged, it may be wiser to have the system replaced.

Excess heat in the engine

A working engine typically coverts about one third of the energy derived from the combustion of fuel into work that powers the vehicle.  That means about two thirds is converted into heat, which needs to be removed from the engine.  Half of the heat in the engine exits the vehicle through the exhaust pipe, while the other half is removed by the coolant.  If all the hoses and fluid levels are in working order and your engine is still overheating, you might want to check what type of coolant you are using.  Generally speaking, a 50/50 coolant-to-water ratio is recommended.  You should double check to make sure the coolant you use has the proper ratio as specified in your owner’s manual.


  • 5 Common Reasons Cars Break Down
    Jun 17, 2015

    Although they may vary greatly in look, the majority of cars are pretty similar when you look at what makes up the actual vehicle. Because of this, most cars are affected by a lot of the same issues. Today, we take a look at five of the most common reasons your car breaks down. 1. […]

  • How to Change a Flat Tire On Your Car
    Apr 23, 2014

    It’s pothole season, and that means your tires are exposed to dangerous crevices on a daily basis. Particularly nasty potholes can puncture your tire, leaving you high and dry, unless you know how to fix the problem (or you have AAA). Changing your tire is something everyone should know how to do, so follow along […]

  • Car Repairs in Minnesota Cheaper Than Most
    Jul 2, 2014

    Back in January we wrote a post on how Minnesota was among the cheapest states for auto repair. Although the findings were based on 2011 data, we’re happy to contribute to a statewide auto industry that puts its customers first. After all, we don’t call ourselves Affordable Auto for no reason! Just this week, CarMD.com came […]