Symptoms of a Blown Head Gasket

The engine of your car is divided into two distinct parts: the cylinder head, which houses the valves, spark plugs, and camshaft(s), and the cylinder block, which houses the pistons and cylinders. The head gasket sits in cushioning between these two substantial engine components. The head gasket, one of the most important gaskets in your engine, is made to keep coolant and engine oil from leaking into the cylinders as well as to the outside. It also serves to seal the cylinders’ firing pressure.

symptoms of a blown head gasket

When sealing in-cylinder pressure, coolant, and engine oil flowing via casting ports, the head gasket must endure the strains caused by the two surfaces expanding, contracting, warping, and rubbing together. There are worse things than having to pay for a blown head gasket. Expenses like paying to replace an entire engine or fix a fractured engine block! However, a blown head gasket will swiftly cause irreparable damage to your car if it is not immediately fixed, in addition to being a big issue in and of itself.

Well, in today’s article, we’ll be looking at the most common signs and symptoms of a blown head gasket. Nevertheless, we’ll be discussing the answers to the following questions:

What causes a head gasket to blow?
How long does a head gasket last
What are the signs and symptoms of a blown head gasket?
How to prevent the head gasket from blowing?
How much does it cost to replace a head gasket?

Ok, let’s dive in!

Contents

What causes a head gasket to blow?

The engine of your car functions in harsh conditions with considerable heat. Your engine could overheat and rupture a head gasket if this heat rises over normal. The additional heat causes the cylinder head and engine block to expand excessively, which leads to a head gasket failure. Another reason for head gasket failure is detonation, which harms the armor or fire rings and lets cylinder pressure seep past the armor. Making sure your cooling system is in good shape is the best approach to prevent a head gasket failure because frequent overheating or driving after the car has overheated are the major causes of head gasket failures.

How long does a head gasket last?

Head gaskets typically last 200,000 miles, which is about the lifespan of most vehicles. Thus, if you take care of your vehicle and adhere to the recommended maintenance schedule, a blown head gasket should never occur. The best approach to maintaining crucial components like the head gasket is to stick to the manufacturer’s recommended maintenance schedule. Make sure to use a high-quality product that provides great engine protection while cleaning the coolant or antifreeze.

What are the signs and symptoms of a blown head gasket?

The following are the most common signs and symptoms of a blown head gasket:

Engine Overheating
Low coolant level
White Smoke Coming from the Tailpipe
Rough Idle
Milky Build-Up Under Oil Cap
Engine Oil Appears to be Contaminated

Engine Overheating

The most typical sign that your car’s head gasket is deteriorating is an overheating engine. The engine will have to work harder to produce power if the head gasket fails. Additionally, a burst head gasket might result in coolant loss in your car, which can impair the engine cooling system and exacerbate the overheating issue.

Low coolant level

The engine may begin to use coolant if the head gasket between a coolant channel and one of your engine’s combustion chambers fails. Additionally, because the coolant level is insufficient, this may cause the engine to overheat. Other signs of a coolant-burning engine may occur.

White Smoke Coming from the Tailpipe

Since engine coolant is primarily made of water, when the coolant gets used in the engine, water vapor is visible as white smoke coming from the exhaust. This is an indication that the engine is consuming coolant as a result of a failing head gasket. If the coolant level is chronically low but the engine isn’t losing coolant, you might want to check for leaks elsewhere in the cooling system or at the engine’s exterior, where the engine block and cylinder head meet.

Rough Idle

Between two combustion changers, the head gasket can potentially fail. A high-pressure level must remain inside the cylinders of the engine at all times. The engine will run badly and have a rough idle when the head gasket fails since it won’t be able to maintain the proper level of pressure. A rough idle should not be ignored even though it is not a certain sign of a faulty gasket head.

Milky Build-Up Under Oil Cap

It is simple to determine whether the head gasket on your engine has blown. Just look underneath the oil-filling cap. The inside of the oil cap will be mostly dry if the gasket is intact. You most likely have a gasket leak if you find a milky, brownish-yellow material that is about the thickness of a milkshake. The milky stuff is coolant and oil that has leaked past the head gasket into the engine oil, polluting it. Once polluted, engine oil is no longer able to adequately protect your engine. You should obtain a head gasket replaced as soon as you suspect this has happened.

Engine Oil Appears to be Contaminated

We all know that water and oil don’t mix, but if coolant contaminates the engine oil, the resulting mixture loses its ability to lubricate. Engine coolant may combine with the engine oil system due to a head gasket leak. If you suspect a head gasket leak in your automobile, taking off the oil filler cap and inspecting the underside is an excellent first step. The resulting thick, frothy fluid can accumulate there. If there is a frothy, light-colored oil buildup there, coolant is probably contaminating the engine oil.

How to prevent the head gasket from blowing?

Here are a few preventive measures:

Check the flatness

Always examine the surfaces of the cylinder head and block for flatness. Check clearances by laying a straight edge over the deck(s) and using a feeler gauge. You will need to have the surface resurfaced since too much clearance indicates that the surface is not flat enough to maintain a seal.

Look for surface flaws

On the head or block decks, any pitting, corrosion, cracks, ridges, or low spots are potential leakage routes. You must have the head or block resurfaced if you find any of these faults.

Carefully handle the heads and gaskets

Before handling cylinder heads and head gaskets, wash your hands. It’s possible for grease or dirt to wind up on the head surface or the gasket, which would interfere with a tight seal. Also, never place a clean cylinder head on the floor of your garage, especially not on the deck. Dirt may adhere to the deck due to the head’s weight.

surface cleaning on the deck

Look for any old gaskets or sealants on the deck surfaces. Remove any leftover debris with a wire brush, a surface degreaser, or a gasket remover. To prevent gouging the surface, use a non-metallic scraper on aluminum heads.

Look at the head bolt holes

Bolt holes with distorted threads, dirt, or other debris can lessen clamping force much as broken bolts can. Run a bottoming tap down each bolt hole, unless the instruction manual specifies otherwise. To prevent the highest threads from lifting above the deck surface when bolts are tightened, the tops of the holes should also be chamfered.

Never use an old bolt again

Modern automobiles frequently use torque-to-yield (TTY) head bolts, which when inserted gradually expand due to an elastic action, increasing the clamping force of the fasteners. You cannot use TTY bolts again because that stretch is permanent. If you do, they can extend over the rated torque limit and either fail or tighten incorrectly.

Use only intact head bolts

Examine the threads on your bolts carefully, and replace any with damaged or worn threads. Threads that are dirty or damaged might produce erroneous torque readings and reduce the clamping force of the bolt as a whole. If you use washers, make sure to grease the underside of the washers as well.

Only apply sealer when necessary

With a few exceptions, most modern gaskets don’t need RTV silicone or other sealants. They may disrupt any factory-applied sealing coatings and result in subpar gasket performance, degradation, or total gasket failure. When the head is cranked down, RTV silicone can also leak out and spill into the combustion chamber(s) or cooling jackets.

How much does it cost to replace a head gasket?

Five different mechanics across the nation provided estimates for the replacement of a head gasket in three example vehicles (a Honda Civic, a Ford F-150, and a BMW 740i). We observed individual estimates ranging from $2,886.50 to $6,047, although average replacement costs per car ranged from around $3,400 to $5,500.

Throughout our assessment, the cost of parts for each vehicle remained mostly the same, while the cost of labor varied significantly. It makes it natural for labor prices to vary by kind of vehicle. (Replacing the head gasket on some vehicles is quite simple; on others, the procedure is more involved.)

FAQs

How do I know if my head gasket is failing?

The following are the most typical warning signals of a damaged head gasket:

White or milky oil: When coolant seeps into the oil and the two combine, a milky white liquid is visible on the dipstick or in the area around the engine’s oil filler cap.
White exhaust smoke: Coolant that enters the combustion chamber burns or evaporates and produces this color when it does.

What are the first signs of a blown head gasket?

The following are the first and main signs of a blown head gasket:

Engine Overheating
Low coolant level
White Smoke Coming from the Tailpipe
Rough Idle
Milky Build-Up Under Oil Cap
Engine Oil Appears to be Contaminated

What can be mistaken for a blown head gasket?

Many automobiles frequently experience coolant and oil leaks. You don’t necessarily have a blown head gasket just because you notice a leak. However, if you see that most of the oil or coolant is leaking from the engine block, it can be a sign that the head gasket is no longer keeping a seal.

Can a car run with a bad head gasket?

The short answer is yes, but it is not advised. The more you ignore a blown head gasket, the more probable it is that your engine and wallet will suffer. The most crucial and essential components of any engine that serve to seal off compartments are gaskets.

What causes head gasket failure?

Making sure your cooling system is in good shape is the best approach to prevent a head gasket failure because frequent overheating or driving after the car has overheated are the major causes of head gasket failures.

Can a head gasket be fixed?

The majority of blown head gaskets are effectively fixable without a technician. A head gasket leak may often be fixed with one of our solutions, but there are some situations where the damage is too severe and you will need the help of a professional to replace the gasket.

How do you fix a blown head gasket without replacing it?

Flush the cooling system after removing the thermostat.
Add water to the system.
As the car idles, slowly add BlueDevil Head Gasket Sealer to the radiator.
Place the radiator cap on and give the engine a minimum of 50 minutes to idle.

That is all for this article, where we looked at the most common signs and symptoms of a blown head gasket. Nevertheless, we got to discuss the answers to the following questions:

What causes a head gasket to blow?
How long does a head gasket last
What are the signs and symptoms of a blown head gasket?
How to prevent the head gasket from blowing?
How much does it cost to replace a head gasket?

We hope it was helpful. If so, kindly share it with others. Thanks for reading; see you around!