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"Why is my car engine over heating? What causes an engine to overheat"
I hear this question all the time on my websites and especially during the hotter summer months. I made this short video to help you determine what might be the cause of your overheating problem and what you can rule out as not causing the issue before you go to your mechanic. This can save you some time, frustration and money by doing so.

"My engine overheats at freeway speeds"

When you are on the freeway you have lots of airflow across the radiator which helps remove the heat that the engine antifreeze/coolant has accumulated from the cooling system. Since the engine is running at a much higher RPM than that at idle, the water pump is spinning around and pumping coolant at a much higher rate as well.

If there is a restriction in the radiator, the coolant will not be allowed to circulate fast enough inside the engine. The coolant will basically be roadblocked inside the radiator due to the restriction. A radiator usually gets build up of rust, minerals and calcium type deposits at the BOTTOM of the radiator. This restriction really can not be removed by "flushing" with a garden hose. In most cases this restriction will require a new radiator.

Think of this type of engine overheating problem like this. You are trying to run a 10 mile marathon, but you have to do it with your mouth taped shut. You can walk with your mouth shut but running at full steam for a long distance requires more air than your nose can provide. A restricted radiator is the biggest culprit in an engine overheating complaint on the freeway or at higher speeds. Although, if the radiator is low on coolant....that can also be the problem, so check coolant level first.

"I am constantly having to add coolant to my radiator, do I have a leak?"

Anytime I hear of a coolant leak or engine overheating complaint I ALWAYS start my diagnosis with a cooling system pressure test.

"My auto mechanic said I have a head gasket leak in my car"

I get tons, literally tons of emails each week with this question. I would say that most of them are NOT having a headgasket problem but rather a lazy auto mechanic problem who failed to do a proper cooling system pressure test.

Here are a few common symptoms I would expect to see if you had a blown headgasket or any other internal coolant leak.

1. Constantly having to add coolant to the radiator, with no visible external leaks found
2. White steam/smoke coming out the tailpipe, and worse or more smoke at freeway speed
3. Failing a cooling system pressure test, meaning the air pressure gauge drops but there are no external leaks to be seen.
4. An engine miss fire, due to coolant leaking inside the cylinders and fouling out the spark plugs. Lack of overall engine power and performance.
5. Usually a yellow check engine light will be on the dash, since the computer sees the engine miss fire and stores that code inside the computer memory.
6. Lack of engine compression. A manual compression test should be done on each cylinder to prove that there is a compression problem with 1 or more cylinder. This is different from the PRESSURE test which I mentioned above.
7. White powdery residue on the inside tip of the spark plug. When coolant enters the cylinder on the inside of the engine (which It should not be doing) the engine is going to try and burn that coolant, which it will have a very hard time doing. This coolant is what causes the engine to miss fire and produce the steam white smoke out the tailpipe. A white powdery residue will some times form on the internal engine tip of the spark plug.

If you have any of those symptoms AND you have rule out all other possible issues then you might want to consider trying this very simple and effective head gasket sealer you can do yourself. I have had great success with it over the years. It's a sealer additive made by K&W, called Engine Block Sealer, but don't use it as the can direction say. I think my way of using it works much better and its much easier.
http://www.myhonestmechanic.com/artic...

Do NOT use a radiator stop leak additive! check out my sites for more free information

http://www.myhonestmechanic.com
http://www.trustmymechanic.com/forum (ask your questions for free on my forum board)