Blown Head Gasket Symptoms and Test

A blown head gasket is sometimes hard to diagnose, often expensive to repair and always a headache. It usually begins with a leaking cooling system that goes unnoticed or a car that is simply not maintained. Suddenly you have a car that overheats and that causes the the head gasket to go bad. This article will help you figure out what to do.

Warning Signs of a Blown Head Gasket

Engine Overheating - This is one of the most common symptoms, but there are other causes too so don’t think that just because your car is overheating that it is a head gasket problem.

Dropping Coolant Levels - If you have to keep adding coolant to your radiator or coolant reservoir but there are no visible leaks then you might have this problem.

Engine Misfire - Usually there are other symptoms as well, but if you have one cylinder in your engine that is misfiring it is possible that is is being caused by coolant leaking into the cylinder and causing it to not fire.

Excessive Exhaust Smoking - This usually happens as the leak gets worse. More and more coolant pours into the cylinders and is being burned up by the combustion process which creates steam, but it looks like smoke coming out or your exhaust.

What I have listed above the most common blown head gasket symptoms - If you are facing a combination of these problems, then your head gasket may be in trouble.

How to Check for a Blown Head Gasket

One of the best ways to diagnose this problem is to use a combustion leak tester. Basically this is a device that detects exhaust gases in the coolant.

It consists of a piece that fits into the neck of your radiator (with the radiator cap off) and is filled with a blue fluid. You then start the car and let it run for a few minutes. If the fluid turns to yellow, then you have exhaust gases in your coolant indicating a cracked head gasket.

Another way to check is to use a leak down tester. This is a cheap tool but you do need a source of compressed air.

What is does is injects pressurised air into the cylinder. With the piston at TDC on the compression stroke it will be able to tell you if the air is escaping through the valves, rings or cylinder head.

If you still have any unresolved vehicle problems or questions, you can ask an auto mechanic online. For expert answers specific to your vehicle's make and model, I recommend JustAnswer Car. They have a large pool of certified mechanics to answer your questions for a small fee and you can also browse their answers to other users for free.

Should I Try a DIY Head Gasket Repair?

Unfortunately this type of repair is usually very costly, and not something that most DIYers should attempt. It is a job that requires very in-depth knowledge of cars as well as a good level of skill to perform.

Unless you have a lot of mechanical experience and an extensive tool collection, this would be an extremely hard job to pull off.

I have tried this job in a friend's garage when I didn't have much knowledge on it and I have also done this as a professional technician with years of experience. Speaking from experience, if you try to do it yourself... chances are that you will end up making things worse because there are just so many things that can go wrong.

Even though this gets very expensive when you take your car to a mechanic it is still worth it. That is provided that you have a good mechanic that you know and trust. Click here to find out how much a blown head gasket repair cost.

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