Top 6 Symptoms of Blown Head Gasket (Replacement Cost)

April 17, 2022 / By

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Did you suddenly start noticing some awkward signs such as sluggish engine performance, overheating, colored coolant, or leaks from the engine bay? If you see any of these signs, chances are that you’ve got a blown head gasket.

With time, everything in a car would wither, wear out, or become extremely weak due to aging and then breakdown. The head gasket is a very important part of the engine; if anything happens to the head gasket, the engine stands at a very big risk.

Head gaskets can break down due to several reasons, and when that happens, there are some symptoms you’d notice. One of the most common problems car drivers face is a blown head gasket, and this article explains the symptoms of blown head gasket.

What is a Blown Head Gasket?

The head gasket is located between the cylinder heads and the engine blocks; it helps the flow of coolant and oil throughout the engine to ensure efficiency and optimal performance. Hence, when the gasket is bad, the engine suffers greatly, and may likely break down.

A blown head gasket simply means the head gasket has been damaged – physically broken (blown) due to quite a several reasons, which include overheating.

Having a blown head gasket is quite a serious issue that needs to be tackled as early as possible before other crucial engine parts start getting affected too.

But how do you know you’ve got a blown head gasket? The signs you’re experiencing with your car may be symptoms of another faulty device/component, and not necessarily the head gasket.

That said, hereunder, we’ve explained the various possible signs that depict a blown gasket head and what actually causes the gasket to fail.

Symptoms of Blown Head Gasket

Actually, a leaky gasket and a blown head gasket exhibit the same symptoms regardless of the car type and model.

When you notice any of these signs, it is vital to have the head gasket checked and repaired/fixed as soon as possible to save your engine from experiencing fatal damage.

1. Thick White Smoke Coming Out From The Tailpipe

One of the common signs of a blown head gasket is white smoke coming out from the exhaust pipe. This happens when the coolant liquid gets into the combustion chamber; the white smoke is the effect of the coolant mixing with the exhaust fumes.

So, when you see this happening, chances are that the head gasket is faulty.

2. Constant Coolant Loss Without Leak

If the coolant in the car’s coolant reservoir keeps going down drastically without any sign of leaks, it could be the head gasket causing it. How does this happen? When the gasket is blown/leaky, it makes coolant burn off while trying to get into the engine.

So, although there’s no sign of leaks, the coolant would be reducing drastically because it’s not getting to the engine.

Yeah, since the engine is hot already, the coolant would try to cool it down, but since it’s not getting into engine parts, it won’t keep the engine cool, and as such, would continue to flow incoherently in an attempt to do that. The consistent incoherent flow is what causes the coolant loss without any sign of leakage.

3. Engine Overheating

Yes, there are a lot of things that can cause a car engine to overheat – a blown head gasket is one of those things.

When an engine constantly overheats, it weakens the metallic components in the engine bay – causing some of them to either melt or break. Overheating is one of the major factors that cause a head gasket to blow.

4. Milky Build-Up Under Oil Cap

Another common sign of a blown head gasket is milky build-up under the oil filler cap. If the head gasket is functioning well, the oil filler cap would typically be dry all the time; but, if the head gasket is bad, the filler cap would have milky build-ups.

The milky substance is the result of coolant mixing with oil – the thickness is like that of a milkshake. When you see this, there are higher chances that you’ve got a gasket leak to deal with. More so, it is important to note that contaminated oil is not beneficial to the engine.

5. Rough Idling

Rough idling is the minor vibration that happens when your car is not in motion – but is turned on. This usually happens when you’re parked or stuck in traffic.

So, if you notice that you idle rough, it is a sign of a bad head gasket. Notwithstanding, rough idling can also be caused by pretty other reasons, including a bad sensor/valve

6. External Leaks

If the situation is severe, you’d see leaks under the engine bay. When you see liquid leaking from the engine bay, it’s a sign of a blown head gasket.

The liquid could be coolant or oil. Again, there could be other reasons why oil or coolant would leak out from the engine bay – inspect the car to find out the actual culprit.

What Causes a Blown Head Gasket?

Nothing gets damaged without a cause; if you’ve got a blown head gasket, something caused it. Actually, there are several things that can cause head gasket damage, but these mentioned below are the commonest causes.

1. Overheating

You don’t have to be surprised, overheating is both a symptom of head gasket failure and a cause of head gasket failure. When a car overheats, the excessive heat affects virtually all the components in the engine bay – causing most of them to melt or break down (get blown).

The head gasket is one of the core components that gets easily affected by overheating. So, if an engine is overheating, the cause should be fixed as early as possible before crucial components may get affected, therefore attracting costlier repair costs.

2. Hard Impact

If you had an accident with the car, depending on the severity of the impact, the head gasket may get fractured and stop performing as it ought to.

This is not so common, but if you ever had a collision with an object or another car, have the head gasket inspected thoroughly while repairs are being done to the car as a result of the collision.

3. Too Many Miles

Once you hit 100k miles on a car, most definitely, most of the components would be weak, and that includes the head gasket. High mileage is one of the major causes of head gasket failure.

Head Gasket Replacement Cost

Head gasket repair or replacement is costly, which is why most drivers try to keep driving with a blown or leaky head gasket. On average, it costs around $1,200 to repair or replace a bad head gasket. The cost can go over $2,000 in some situations.

Now, that’s a lot of money, and you should be thinking of how to prevent being faced with a blown head gasket. Interestingly, there are approaches you can take to minimize the risk of blowing your car engine’s head gasket.

How To Prevent Head Gasket Problems

The simple way to prevent head gasket problems is to be proactive and drive carefully. When your car starts rough idling or the engine seems to be overheating, look out for the cause and fix it immediately. Allowing such situations to go on a little longer can cause the head gasket to fail.

Other tips include:

Conclusion: Signs of a Blown Head Gasket

Explained in this article are the common signs and symptoms of blown head gaskets. If you experience any of these signs, you need to act proactively to save yourself a reasonable cost on head gasket repairs or replacement.

In most cases, if the head gasket is badly damaged, it cannot be repaired, a full replacement would be done.

Interestingly, this article also highlighted some useful tips on how to prevent head gasket problems. Hopefully, you got all the information you needed regarding head gaskets – this applies to all car models and variations.

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