I just checked my radiator coolant the other day and now I have car overheating problems!
- Did I break something?
- Why is my car overheating?
- What can I do to avoid this?
But before you ask Siri where is there car help near me, here are a few DIY tips…
Listen:
Car overheating is a common problem in Arizona HEAT. There are no exceptions!
All car brands and models, Ford, Chevrolet, Honda, BMW, etc. can overheat under the right circumstances, which is why you need to be proactive about car maintenance.
Let’s look at 6 reasons why engines overheat:
Reason #1 – Leaks!
Is there a green puddle of liquid on your driveway every day?
This could be from a leaking radiator hosed caused by a loose hose clamp…
…or worst, it could be a radiator or heater hose that has gotten soft and is about to burst.
Coolant leaks from radiator hoses and clamps are the most common reason why cars overheat…
….and almost always, they can be caught before an overheated car leaves you and your family stranded on a hot Arizona day.
If you see any fluid that looks green, yellow, or like water, coming from under the engine, you most likely have a radiator coolant leak.
Reason #2 – Water Pump
A water pump leak only has one fix, replace the part, and replace it fast!
Water pumps are powered by the engine, usually via a fan belt that wraps around the water pump pulley.
When I water pump starts leaking, it normally means the bearing has worn out and now the seal is leaking.
Coolant will leak from a small hole called a “weep hole” normally on the bottom of the pump.
When this happens, disaster can be slow, almost unnoticeable…
One day your cooling system dries up and your car overheat.
Checking your coolant level regularly will tell you if something is wrong because when your coolant is always low, it means it’s leaking somewhere.
Time to inspect all your clamps, hoses, and around your water pump!
Reason #3 – Blown Head Gasket
A blown head gasket is a serious problem and can cause major engine failure and out of the pocket expenses if it’s not caught in time.
Unless you’re an experienced mechanic, there’s not much you can do when this happens.
But here’s what to look for that can indicate a blown head gasket:
- The water level is always low but you can’t find any leaks on hoses, clamps, or around the water pump.
- Noticeable steam and bubbles come out of the radiator when the cap is removed to add water when the engine is running.
- Water or green coolant is coming out of the exhaust pipe (not morning condensation).
- The engine is running rough after the car overheated.
- When you check the oil, it’s above the full mark and the coolant is on the dipstick.
- The car overheats just driving around the block.
Any or all these indicators will help you determine if your car has a blown head gasket.
Reason #4 – Blocked or Seized Thermostat
Thermostats help engines regulate temperature to keep your engine coolant from boiling and maintain normal operating temperature.
Thermostats are an internal part and cannot be seen.
They have a round opening that allows fluid to pass from the radiator into the engine block.
This opening is controlled by a thermometer, filled with beeswax that expands to force the valve open at just the right temperature for your specific car model.
Sometimes these valves become frozen in the closed position and water isn’t allowed to flow through the engine block and heads to cool the engine off.
When this happens, the water in the radiator boils and can burst a hose, or crack the radiator.
The only solution for a seized thermostat is to replace it and the lost coolant.
Also a good inspection of hoses, clamps, and other engine parts should be done when the engine has overheated and burst a hose or the radiator cap.
Reason #5 – Cooling Fan is NOT Turning
Older cars have a fan that is turned by a fan belt powered by the engine.
Newer cars have a cooling fan that is powered by electricity and is started by a thermal switch and relay.
When both types of fans stop turning normally, your radiator pressure will build up because of boiling coolant until your car overheats.
Warning! Always be very careful when watching a running engine. Never put your hands near a running engine or fan belts.
Reason #6 – Bad Radiator Cap
Let’s go back to the opening question about whether you broke something when you checked your radiator coolant level…
When you removed the radiator cap to check your coolant, the cap seal that presses against the inner throat of the radiator could have split or come off without you noticing.
Also, the cap itself may have gone bad and now the spring no longer has enough strength to keep the seal closed under normal operating temperatures.
When radiator cap springs are weak, coolant is constantly seeping through the seal into the overfill tank…
…and without a tight enough seal, the radiator can’t build up the suction to return and hold the fluid so it continues to get lower until there’s not enough coolant circulating to cool the engine.
Radiator caps are cheap and the easiest thing to replace before taking the car to the dealer or an auto repair shop.
Watch this video on how to replace the engine in a Honda Accord
Conclusion:
I covered 6 reasons that could answer why you have a car overheating problem so YOU can avoid getting stranded.
But if your engine overheated so badly it cracked the block, you might want to consider buying a used car as an option rather than spending $1000s to replace it.
If that’s the case, I recommend reading the 31 Point Used Car Checklist To Help Avoid Buying A Lemon to help you.
DIY Tip:
Here’s a dummies guide on how to check your engine coolant…
Don’t be stranded in the Arizona HEAT in the middle of summertime without water! Always keep a couple of bottles of clean drinking water in the car.
