A blown head gasket is one of the worst things that can happen to your vehicle. If you don’t get it repaired quickly, the engine can become severely damaged, which will cost huge sums of money to sort out.
One cheap and effective solution is to use a head gasket sealer. These products work quickly, provide a permanent fix, and cost just a fraction of the price of a replacement head gasket.
However, choosing the first head gasket sealer you come across can cause more problems than it solves. You need to make sure the product is suitable for your vehicle, which is why we’ve compiled this list of the best head gasket sealers on the market in 2024.
- Guide to Choosing the Right Head Gasket Sealer
- Top 8 Best Head Gasket Sealers 2024
- 1. Best Overall Head Gasket Sealer: Bar's Leaks Permanent Head Gasket Fix
- 2. Best Premium Head Gasket Sealer: Bar’s Leaks Blown Head Gasket Repair
- 3. Best Budget Head Gasket Sealer: K-SEAL Coolant Leak Repair
- 4. Best All-Purpose Head Gasket Sealer: K&W Permanent Head Gasket & Block Repair
- 5. Best Bulk Head Gasket Sealer: BlueDevil Head Gasket Sealer
- 6. Best Head Gasket Sealer for Repairing Cracks: K&W FiberLock Head Gasket & Block Repair
- 7. K&W Permanent Metallic Block & Radiator Seal
- 8. Steel Seal Head Gasket Sealer
- Everything You Need to Know About Head Gaskets and Sealers
- Frequently Asked Questions
- Wrapping Up
Guide to Choosing the Right Head Gasket Sealer
It’s important to choose the right head gasket sealer for your vehicle, as choosing the wrong one can cause even bigger problems, such as clogged heater cores and sticky thermostats, so be sure to read our complete guide to choosing a proper sealant. Some sealers can’t be used for both diesel and gasoline engines, and others aren’t compatible with antifreeze or coolant.
This guide includes everything you need to know about head gasket sealers. We’ll go over all of the major things to look out for so that you can pick the right product the first time around.
Pro Tip: If you suspect that you have a problem with your head gasket, try not to drive the vehicle. This will prevent further damage that may be irreversible!
How Do Head Gasket Sealers Work?
Head gasket sealers contain chemicals that seek out and plug small cracks. The immense pressure and high temperatures within the engine’s combustion chamber cause the sealer’s chemicals to react, forming a rock-solid seal that instantly stops leaks.
Head gasket sealer is added to your vehicle’s cooling system via the radiator or overflow tank. With the engine running, the sealer makes its way into every nook and cranny, plugging small holes and leaks along the way.
As the name suggests, head gasket sealers are primarily used to fix problems with blown head gaskets. However, many of these products also fix other problems with cooling systems, such as leaking radiators, water pump casings, cylinder heads, and engine blocks.
This can be immensely useful as you may not know where the leak is originating from.
Key Things to Consider When Buying Head Gasket Sealer
Don’t just buy the first head gasket sealer you come across, as it might not be the right one for your vehicle. There are three key things to consider, which we’ve listed below.
Engine Compatibility
It’s crucial to check whether the head gasket sealer is compatible with your vehicle’s engine. Most head gasket sealers are designed for use in both diesel and gasoline engines, including every option on our list, but it’s always wise to double-check before buying if you’re looking elsewhere. Some are safe to use with antifreeze, however many are not. We’ll point this out in every review.
In addition to that, some head gasket sealers cannot be mixed with your engine’s coolant. This is because many products contain a chemical called sodium silicate, which clumps up when introduced to antifreeze. If a product contains sodium silicate, chances are you’ll need to drain the coolant and flush the system before and after use.
Amount Needed
For most engines, one bottle of head gasket sealer will be enough to repair any leaks. However, for bigger engines or for multiple treatments, you may need to purchase more than one bottle.
Be aware that some products are stronger than others, so you must use the right amount to avoid causing further damage. We’ve triple checked how much you need to use depending on the size of your engine, and we’ll disclose this information in each review.
Preparation and Ease of Use
While some head gasket sealers are easy to use, others require more knowledge and effort. It may be necessary to drain the coolant from the engine and then perform a flush before using some products, and the same again once the treatment has finished.
That’s fine for DIY mechanics who know what they’re doing, but for the everyday person who doesn’t know much about engines, it might be too complicated. These people may just want to stick with a simple pour-and-go product.
Now that you know why you might want a head gasket sealer and how to choose the perfect one for you and your car, let’s get into our picks for the best products available today.
| Product | Contains | Quantity | Antifreeze safe | Requires drain/flush | Downtime | Rating |
|---|---|---|---|---|---|---|
| Bar's Leaks Permanent Head Gasket Fix | Sodium silicate, copper | 1 x 24 oz bottle | Yes | No | 15 minutes | 5 |
| Bar’s Leaks Blown Head Gasket Repair | Sodium silicate, titanium dioxide, triazinetriethanol | 1 x 33.8 fl oz bottle | Yes | No | 45 minutes | 5 |
| K-SEAL Coolant Leak Repair | Zinc gluconate, triazinetriethanol, sodium tetraborate, copper, aluminosilicate refractory ceramic fibers | 1 x 8 oz bottle | Yes | No | 20 minutes | 4.5 |
| K&W Permanent Head Gasket & Block Repair | Water, sodium silicate, aluminosilicate refractory ceramic fibers, copper | 1 x 32 oz bottle | No | Yes | 24+ hours | 4.5 |
| BlueDevil Head Gasket Sealer | Sodium silicate, ethylene glycol | 1 x 32 oz bottle | No | Yes | 2 hours | 4.5 |
| K&W FiberLock Head Gasket & Block Repair | Water, sodium silicate, glycol monobutyl ethers, copper, aluminum, Kevlar® | 1 x 32 oz bottle | Yes | No | 15 minutes | 4 |
| K&W Permanent Metallic Block & Radiator Seal | Water, sodium silicate, cellulose, aluminosilicate refractory ceramic fibers | 1 x 16 oz can | No | Yes | 24+ hours | 3.5 |
| Steel Seal Head Gasket Sealer | Proprietary ingredient, ethylene glycol | 2 x 16 oz bottles | No | Yes | 30+ minutes | 3.5 |
Top 8 Best Head Gasket Sealers 2024
1. Best Overall Head Gasket Sealer: Bar's Leaks Permanent Head Gasket Fix
Editor’s Rating:
Quick Facts:
- Contains: Sodium silicate, copper
- Quantity: 1 x 24 oz bottle
- Antifreeze safe: Yes
- Requires drain/flush: No
- Downtime: 15 minutes
Bar’s Leaks Permanent Head Gasket Fix provides a permanent solution for pesky head gasket problems. It’s suitable for use with both gasoline and diesel engines, and it can be used by absolutely anybody, as there’s no need to drain or flush the coolant. Due to its ease of use, you can be back on the road in just 15 minutes.
While it’s most effective at fixing head gaskets, this product can also repair block leaks and cracked seals – that’s useful if you’re not 100% sure of where the leak is coming from. It’ll repair small, medium, and large leaks, however it isn’t suitable if there’s coolant in the oil, or if there are bubbles present in the coolant.
Preparation and Usage
No draining or flushing is necessary with this product.
Using the product is easy; simply pour it into the radiator or overflow tank, and then let the engine idle for 15 minutes. After that, you’re free to drive your vehicle as usual!
Amount Needed
One 24 oz bottle is enough to treat most 6 and 8 cylinder engines. 4 cylinder engines will only need half a bottle.
The exact amounts to use are as follows:
- ½ bottle treats 1 to 1.99 gallons of cooling system capacity (4 cylinder engines)
- 1 bottle treats 2 to 4 gallons of cooling system capacity (6 and 8 cylinder engines)
- For larger engines, use 1 bottle for every 4 gallons of cooling system capacity
Our Verdict
Easy to use, highly effective, and safe for most vehicles. This product will suit most people, however it’s not the best option for more serious leaks, and those who need to plug major holes should look towards a premium product like the Bar’s Leaks Blown Head Gasket Repair instead.
Pros
- Offers great value for money
- Simple enough for anybody to use
- Just 15 minutes downtime
- One bottle treats 4, 6, and 8 cylinder engines
- Bar’s Leaks is a well-known brand
Cons
- Not suitable for major issues
Editor’s Rating:
Quick Facts:
- Contains: Sodium silicate, titanium dioxide, triazinetriethanol
- Quantity: 1 x 33.8 fl oz bottle
- Antifreeze safe: Yes
- Requires drain/flush: No
- Downtime: 45 minutes
Bar’s Leaks Blown Head Gasket Repair can sort out intake gaskets, cracked cylinder heads and blocks, leaking heater cores, radiator leaks, and leaking freeze and core plugs – in addition to blown head gaskets, of course.
It’s the strongest leak repair product that Bar’s Leaks has to offer, as it uses carbon fiber to help create a strong and permanent seal. This is the product to choose if you have major head gasket issues, such as bubbles in the coolant or coolant mixing with the engine oil.
Preparation and Usage
As with Bar’s Leaks’ other head gasket sealer, this product also contains antifreeze safe sodium silicate, so there’s no need to drain or flush the coolant.
All you need to do is fill the radiator or overflow tank with the required amount and then reinstall the radiator cap. Ensure that the heater is set to hot and the fan on maximum, then run the engine until normal operating temperatures are reached.
The thermostat needs to open for it to work properly, so you may have to run the engine for 30 minutes. Once done, take your vehicle for a 15-minute drive, then check for leaks.
Larger leaks may take several days to fully seal, however in most cases, the results are instant.
Amount Needed
One 33.8 oz bottle will treat engines with up to 8 cylinders. For smaller or larger engines, use the following amounts:
- ½ bottle for 1.5 to 2.49 gallons (4 cylinder engines)
- 1 bottle for 2.5 to 5 gallons (6 and 8 cylinder engines)
- 1 bottle for every 5 gallons in engines with a larger cooling system capacity
- 2 oz per quart of cooling system capacity in very small engines
Our Verdict
Bar’s Leaks Blown Head Gasket Repair is one of the strongest head gasket sealers on the market. It’ll repair more serious leaks and create a strong seal that lasts.
Pros
- One of the strongest products on the market
- Contains antifreeze safe sodium silicate
- Reinforced with carbon fiber for a stronger seal
- Repairs other leaking areas of the engine
Cons
- Takes a little longer to use
3. Best Budget Head Gasket Sealer: K-SEAL Coolant Leak Repair
Editor’s Rating:
Quick Facts:
- Contains: Zinc gluconate, triazinetriethanol, sodium tetraborate, copper, aluminosilicate refractory ceramic fibers
- Quantity: 1 x 8 oz bottle
- Antifreeze safe: Yes
- Requires drain/flush: No
- Downtime: 20 minutes
K-SEAL is a brand that’s trusted by professionals all across the country. They specialize in making leak repair products, so they know their stuff. Despite the small-sized bottle and affordable price, it’s seriously potent stuff!
K-SEAL Coolant Leak Repair can fix cracks in radiators, head gaskets, water pump casings, cylinder heads, and engine blocks. No matter where your leak is, K-SEAL will seek it out and repair it. Its microfiber technology meshes together and forms a strong and permanent seal when exposed to the high temperatures and pressures inside the combustion chamber.
This product is best suited for small leaks.
Preparation and Usage
There’s no sodium silicate in K-SEAL Coolant Leak Repair, so there’s no need to drain and flush the cooling system.
This product is perfect for anybody to use, as you simply pour the contents into the radiator or overflow tank and let the engine idle for 20 minutes.
Once finished, you’re ready to drive your vehicle as normal.
Amount Needed
One 8 oz bottle is sufficient for treating all 4, 6, and 8 cylinder engines.
The exact amounts to use are as follows:
- 1 bottle treats up to 5 gallons of cooling system capacity (4, 6, and 8 cylinder engines)
- 2 bottles will be needed for engines with a larger cooling system capacity
If you need more than one 8 oz bottle, take a look at the 16 oz version of K-SEAL.
Our Verdict
A small but mighty head gasket sealer that can repair different types of leaks. As an added bonus, it’s made in the USA.
Pros
- One bottle treats most engines
- Quick and easy to use; just pour and go
- Microfiber technology creates a strong seal
- One of the cheapest products on the market
- Made in the USA
Cons
- Only recommended for small leaks
4. Best All-Purpose Head Gasket Sealer: K&W Permanent Head Gasket & Block Repair
Editor’s Rating:
Quick Facts:
- Contains: Water, sodium silicate, aluminosilicate refractory ceramic fibers, copper
- Quantity: 1 x 32 oz bottle
- Antifreeze safe: No
- Requires drain/flush: Yes
- Downtime: 24+ hours
K&W Permanent Head Gasket & Block Repair sorts out engine blocks, heater cores, freeze plugs, cooling systems, radiators, and cylinder heads. As it isn’t antifreeze safe, extensive draining and flushing is required, which makes using this product a rather long-winded process.
This may be a good choice for you if you are planning to clean out the cooling system anyway. For most people, the extensive flushing is too time-consuming and hands-on, and on top of that, you’ll have to purchase extra radiator flush and antifreeze.
Preparation and Usage
Extensive draining and flushing is required, and the cooling system must be left for 24 hours to dry out after use.
This product should be added to the cooling system via the radiator. With the cap reinstalled, allow the engine to idle for 30 minutes with the heater on at maximum settings. After that, the system can be drained and left to dry. An additional flush and fresh antifreeze must be added at the end.
If this sounds too complicated or time-consuming, you may want to consider Bar’s Leaks Permanent Head Gasket Fix a quick and easy sealant instead.
Amount Needed
This product comes in a 32 oz bottle, which should be mixed with 3 quarts of water. There are no specific instructions for different sized engines, however this is enough to treat 4, 6, and 8 cylinder engines.
Use the whole bottle mixed with 3 quarts of water.
Our Verdict
Uses nanotechnology to create robust seals. Unfortunately, the entire process from start to finish is very long.
Pros
- One bottle is good for most vehicles
- Uses nanotechnology to seal cracks and leaks
- Effective performance
Cons
- Takes over 24 hours to complete process
- Requires extensive flushing of the system
5. Best Bulk Head Gasket Sealer: BlueDevil Head Gasket Sealer
Editor’s Rating:
Quick Facts:
- Contains: Sodium silicate, ethylene glycol
- Quantity: 1 x 32 oz bottle
- Antifreeze safe: No
- Requires drain/flush: Yes
- Downtime: 2 hours
BlueDevil makes a number of stop leak products, including this head gasket sealer. It’s designed to provide a permanent repair for blown head gaskets, warped or cracked cylinder heads, leaking heater cores, and leaking freeze plugs.
It’s safe to use for most vehicles, however it should not be added to the engine’s existing coolant as it can cause blockages. Having said that, there’s no solid or particulate matter included in the product, so you avoid the risk of clogging the engine (when following the instructions).
Preparation and Usage
As with most of the other head gasket sealers containing sodium silicate, this product also requires that the cooling system is drained and flushed before treatment. In addition to that, the thermostat must also be removed and the cooling system filled with water.
This product is intended for use while the engine is idling and the heater is on the maximum settings. Simply pour into the radiator slowly and allow the engine to idle for 50 minutes with the radiator cap on.
After treating the engine, there’s no need to drain or flush BlueDevil Head Gasket Sealer; it can stay in the system.
Amount Needed
BlueDevil Head Gasket Sealer comes in a 32 oz bottle, which is enough to treat engines with a cooling capacity of 4.5 gallons – that’s most 4 and 6 cylinder engines. For 8 cylinder engines, you may need to use slightly more.
The exact amounts to use for your vehicle’s specific cooling system capacity is as follows:
1 bottle = 32 oz (1 quart)
- Up to 3 gallons cooling capacity: ½ quart
- 3 to 4.5 gallons: 1 quart
- 5 to 6 gallons: 1 ½ quarts
- 6 to 7.5 gallons: 2 quarts
- 5 to 9 gallons: 2 ½ quarts
Our Verdict
An effective and permanent solution. It’s slightly more expensive than some other products, and it also requires a more hands on approach.
Pros
- Contains no solid or particulate matter
- Permanent solution that fixes multiple problems
- Made in the USA
- Comes in a large bottle
Cons
- Takes a couple of hours to fully treat
- Requires draining and flushing before use
6. Best Head Gasket Sealer for Repairing Cracks: K&W FiberLock Head Gasket & Block Repair
Editor’s Rating:
Quick Facts:
- Contains: Water, sodium silicate, glycol monobutyl ethers, copper, aluminum, Kevlar®
- Quantity: 1 x 32 oz bottle
- Antifreeze safe: Yes
- Requires drain/flush: No
- Downtime: 15 minutes
K&W FiberLock Head Gasket & Block Repair contains several unique leak fixing chemicals. One notable chemical is Kevlar, which is usually associated with bulletproof materials.
The product’s fibers do a great job at patching cracks, while nanotechnology seeks out and repairs even the smallest of holes. It also contains Cool-X technology, which is designed to lower engine operating temperatures, thereby protecting the head gasket from extreme heat.
It wasn’t designed, unfortunately, for anything but head gaskets, so if you’ve got other areas of concern you should check out an all-purpose sealer instead.
Preparation and Usage
Designed for everyday people, K&W’s Head Gasket & Block Repair requires no draining and flushing before or after use. Simply pour the product into the radiator, switch the heater to high, and let the engine idle for 15 minutes.
Amount Needed
K&W FiberLock Head Gasket & Block Repair comes in a 32 oz bottle, which is enough to treat up to 7.5 gallons of cooling system capacity. That is sufficient for all vehicles from 4 to 8 cylinders.
- Smaller engines (4 cylinders with a cooling capacity of up to 2.5 gallons) should use just ½ a bottle
- Larger systems (over 7.5 gallons cooling capacity) should use 1 bottle for every 6 gallons of cooling capacity
Our Verdict
Very quick and easy to use, ideal for people who want to get the job done quickly. Contains a unique bunch of interesting chemicals, including Kevlar.
Pros
- No draining or flushing necessary
- Takes just 15 minutes from start to finish
- Contains Kevlar
- Protects engine from extreme temperatures
Cons
- Can potentially clog radiators
- Not ideal for anything other than head gaskets
7. K&W Permanent Metallic Block & Radiator Seal
Editor’s Rating:
Quick Facts:
- Contains: Water, sodium silicate, cellulose, aluminosilicate refractory ceramic fibers
- Quantity: 1 x 16 oz can
- Antifreeze safe: No
- Requires drain/flush: Yes
- Downtime: 24+ hours
K&W Permanent Metallic Block & Radiator Seal provides a permanent seal for head gasket leaks and works with both gasoline and diesel engines. It is suitable for use with a variety of materials, including cast iron and aluminum blocks, and copper and bi-material heater cores.
This product is best suited for DIY mechanics due to it requiring a lot of draining and flushing before and after use. While this will make the process take longer, flushing the cooling system helps remove scale, rust, and corrosion, which is good for your engine’s longevity.
The cooling system must be left to dry for 24 hours, which might be too much downtime for some people.
Preparation and Usage
There are 7 steps to follow when using this product, which includes draining the system of coolant, performing multiple flushes, adding the product to the engine, further draining, drying out, and finally adding fresh coolant.
Amount Needed
This 16 oz can must be mixed with 3 quarts of water before use. This will be sufficient for treating all regular sized engines, regardless of the cooling system capacity.
Our Verdict
This is a slightly different product from the rest as it comes in a can and must be mixed with water. It can cause solidification if added to coolant, so flushing is essential.
Pros
- Provides a permanent seal
- Comes in a one-size-fits-all can
- Suitable for most vehicles
- Popular brand
Cons
- Requires extensive draining and flushing
- Must wait 24 hours for the cooling system to dry out
8. Steel Seal Head Gasket Sealer
Editor’s Rating:
Quick Facts:
- Contains: Proprietary ingredient, ethylene glycol
- Quantity: 2 x 16 oz bottles
- Antifreeze safe: No
- Requires drain/flush: Yes
- Downtime: 30+ minutes
Steel Seal is one of the most expensive products in our lineup, and its exact ingredients are a mystery as their proprietary formula has been withheld. Steel Seal is a lesser-known brand in the US, however, it’s more dominant in the European market.
This product is compatible with gasoline and diesel engines, however it’s not antifreeze safe, so pre- and post-use draining and flushing is necessary.
If you have a large leak, or if there are any cracks in the head, block, pumps, or hoses, then this product may not be the right one for you as it’s better for small leaks.
Preparation and Usage
Before using, check whether there’s water in your engine’s oil. If there is, you’ll need to perform an oil and filter change before using this product.
Draining the coolant and flushing the system is required both before and after using Steel Seal.
As with the other products, Steel Seal enters your engine via its cooling system. The product should be poured into the radiator or overflow tank. The engine may need to idle for 30 minutes, depending on whether the vehicle is roadworthy or not.
Amount Needed
Steel Seal Head Gasket Sealer comes as 2 bottles with 16 oz per bottle. For 6 and 8 cylinder engines, 2 bottles will be enough. 4 cylinder engines will only need to use 1 bottle.
Our Verdict
It does the job, but we feel it doesn’t provide good value for money as it’s expensive with average results, and it’s not the best for big leaks.
Pros
- Well known brand in the UK and Europe
- 100% money-back guarantee
- Comes with 2 bottles
Cons
- Expensive
- The exact formula is unknown
- Not suitable for large leaks
Everything You Need to Know About Head Gaskets and Sealers
At the beginning of this article, we covered the three key things to consider when buying head gasket sealer. There are some additional things to think about, which include the following.
The Benefits of Using Head Gasket Sealer
To ensure you’re picking the right head gasket sealer, it’s important to consider why you need one, as they offer several benefits compared to paying for expensive repairs.
Affordability
Compared to the cost of replacing the head gasket, head gasket sealers are significantly cheaper, ultimately saving you a lot of money.
Ease of Use
Head gasket sealers have been designed for anybody to use, even if you know nothing about engines or head gaskets. This makes them the perfect solution for people with barely any mechanical knowledge: adding head gasket sealer is simple, especially when using products like Bar’s Leaks Blown Head Gasket Repair that don’t require draining or flushing before starting the process.
Little Downtime
Taking your vehicle to the mechanic usually means waiting days before being able to use it again. With most head gasket sealers, including our top overall pick, you can be back on the road in as little as 15 minutes.
Safe and Effective
Provided you use the right product for your vehicle, head gasket sealers are safe for engines and cooling systems. There’s no need to be concerned about additional problems cropping up, and in many cases the fix is permanent.
What It Fixes
If your vehicle has one or more symptoms of a blown head gasket, then the head gasket has probably failed. However, the symptoms are sometimes indicative of something else being wrong. Many head gasket sealers will also solve other problems, such as cracks in radiators, leaking water pump casings, cracked engine blocks, warped cylinder heads, and leaking heater cores.
When choosing the right product for your vehicle, be sure to take a look at what else it can fix besides just the head gasket.
Compatibility
Compatibility is vitally important, so don’t skip this. If you choose a head gasket sealer that’s not compatible with your vehicle for whatever reason, you may end up with even bigger problems, which means even bigger repair bills!
The key thing to look out for here is whether the sealer works with gasoline or diesel engines. Most good head gasket sealers are suitable for both fuel types.
It’s also important to check whether the product is antifreeze safe or not, as dumping it directly into the coolant can cause blockages within the cooling system.
Sodium silicate is one chemical people keep an eye out for, as it’s known to cause problems with antifreeze. In general, if a product contains sodium silicate, it’s likely you’ll have to drain the coolant and flush the engine both before and after use.
How Much to Use
The size of your engine and its cooling system will determine how much head gasket sealer you’ll need to use. Most bottles will be suitable for 4, 6, and 8 cylinder engines, but it’s best to check, as you don’t want to be caught short. If you have a large truck or heavy machinery, you may need to purchase multiple bottles.
In addition to that, you don’t want to overdo it by using too much. If you do use too much, you may cause damage to the engine through corrosion and blockages, which will result in even more issues that only a garage can fix.
Ease of Use
What do you know about engines? If you know nothing about head gaskets, cooling systems, and basic mechanics, you’ll be better off with one of the easier to use head gasket sealers. These are simply poured into the radiator, and there’s no need to drain or flush the coolant. With these pour-and-go head gasket sealers, you won’t need to tinker with any complicated parts of the engine.
On the other hand, if you’re a bit of a DIY mechanic, then you may want to choose a head gasket sealer that has a few more steps involved. If the thought of draining the coolant and flushing the cooling system doesn’t scare you, then it may be worth doing. It’s always good to clean out the cooling system and refill it with fresh antifreeze.
Effectiveness
How long will the repair last for? Most head gasket sealers offer a permanent solution, however the fix may not be effective if there’s extensive damage, or if the leaks are too big.
Head gasket sealers will never be as good as replacing the actual head gasket, but they’re certainly worth a try considering how cheap they are.
In many cases, these sealers keep vehicles running for many more thousands of miles, so there’s no doubt they work for repairing damaged head gaskets.
Downtime
If you can’t be without your vehicle for too long, then you’ll want a quick solution that’ll get you back on the road in minutes. Several of these head gasket sealers take under half an hour to work, so these will be ideal for you.
If you’re not that bothered about your car being off the road for a day or two, then the slower, more involved head gasket sealers might be a better choice.
Chemical Ingredients
Sodium silicate. Some love it, some hate it. It has a reputation for clogging up cooling systems, especially heating cores. That’s because it reacts with antifreeze and forms into a gooey mess. Some products include fibers that can also cause problems if they end up hardening in the wrong places.
If you see a product with sodium silicate in it, you’re best off draining and flushing the coolant, just to be on the safe side. There are, however, a number of products that contain sodium silicate that are actually safe to use with antifreeze, including our top overall pick and its premium extra-strength counterpart.
Avoiding the Wrong Type of Sealant
If you search for head gasket sealers on Amazon, you’ll find many different products, a lot of which are not listed here. Why haven’t we included them? Well, many products are not suitable for head gaskets and are only good for specific types of gaskets, such as intake gaskets, or rubber seals.
You can easily spot these products as they often come in a tin and are referred to as “sealant.” You’ll also know whether they’re right or not by how they’re applied; if you need to pour it into the oil filler cap, or apply it with a brush, it’s not the right one.
The only head gasket sealers you should use will be put into the cooling system via the radiator or overflow tank.
If you’re changing a head gasket yourself, you’ll find that most head gaskets already have a protective material applied. Head gaskets are designed to be a specific thickness and they must be perfectly flat. Applying gasket sealant to a head gasket can alter the thickness, or make the surface uneven, which can result in misfires, compression issues, and other blown head gasket symptoms.
Stick to the products specifically designed for sealing head gasket leaks.
Pro Tip: Never add head gasket sealer to engine oil or fuel. Always put it into the cooling system. Be sure to check the manufacturer’s instructions for more details.
Blown Head Gasket Symptoms
What are the 3 key fluids engines need to run properly? If you answered fuel, oil, and coolant, you’d be correct. These fluids are usually kept separate from one another, although they can end up mixing together if something goes wrong with the head gasket.
Below are some of the main symptoms of a blown head gasket.
Overheating
Overheating is one of the most common symptoms people experience when their vehicle’s head gasket has blown. This is because the coolant is leaking into the combustion chamber, resulting in there not being enough coolant to keep the engine temperatures down.
It’s also one of the more serious symptoms, as the head can warp or crack, especially if the engine runs too hot for too long. This can damage additional parts of the engine too.
Loss of Power
A struggling engine that’s low on power can be a sign of a blown head gasket. You may also notice that your fuel consumption has increased significantly. This is due to the loss of compression within the cylinders, resulting in the wrong fuel to air ratio.
If your vehicle is wasting fuel due to a bad head gasket, you’ll literally be throwing money away!
Creamy Looking Oil
Oil is supposed to be a honey-like color and consistency, not creamy. If you take off the oil filler cap and notice creamy or milky looking oil, it’s not a good sign. It means that coolant has mixed with the oil, and that can often be caused by a blown head gasket.
It’s important to perform an oil and oil filter change if there’s coolant in the oil. Just be sure to only do it after the head gasket issue has been fixed, otherwise the fresh oil will become contaminated too.
Over Pressurized Cooling System
It’s normal for the cooling system to be pressurized when hot, but excessive pressure is not good. If the cooling system is over-pressurized, you may notice cracks in the radiator or the pipes.
Pro Tip: Never open the radiator cap while the engine is warm. There’s a good chance you’ll severely burn yourself – wait until the engine cools down before removing the cap.
Preventing Head Gasket Failure
Wouldn’t you agree that spending a few dollars and a little bit of time preventing the problem is better than spending thousands on fixing it?
As we’ve seen, one of the most common symptoms of head gasket failure is overheating. To avoid the engine from overheating, make sure the cooling system is in good condition. That includes the radiator, thermostat, coolant hoses, and the coolant itself.
Make sure the coolant level is topped up, and if it hasn’t been changed in a while, flush it out and refill with fresh coolant. Check there are no leaks in the piping. A good way to know if there are leaks is to check the coolant level every so often. If it goes down, there’s a leak somewhere.
As they say, prevention is better than cure, and that certainly applies here!
Head Gasket Replacement Costs
The average cost of replacing a head gasket runs into thousands of dollars, typically between $1,000 and $3,000, although it depends on several factors. That’s a huge cost when you compare it to the relatively cheap price of head gasket sealer.
Head gaskets themselves only cost a few hundred bucks at most, so why is the replacement so expensive? Well, unless you’re pretty handy with tools and know what you’re doing, you’ll have to pay a garage to replace the gasket. That’s where the big cost comes in: labor.
It can take anywhere from 5 hours to a couple of days to change an engine’s head gasket. It’s a pretty labor-intensive job, as many parts of the engine have to come off in order to get to the head. On top of that, everything has to be put back together again.
Is it worth replacing the head gasket? If the vehicle is relatively new, or low mileage, you may want to get it replaced. If you’re interested in doing it yourself, be sure to closely follow a guide so that you don’t cause even more problems. If it’s an older vehicle, or you’re strapped for cash, you may be better off with a head gasket sealer.
Remember: don’t ignore the symptoms of a blown head gasket. It’ll only get worse over time, and you may end up needing a replacement engine.
Frequently Asked Questions
Do Head Gasket Sealers Really Work?
Yes, head gasket sealers are an effective way of repairing a blown head gasket, assuming it isn’t severely damaged. For minor leaks, head gasket sealers can provide a permanent fix while saving you a lot of money.
How Long Will the Head Gasket Sealer Last?
How long the sealer lasts depends on several factors, such as how bad the leak is and the product you use. For most small leaks, head gasket sealers can last a very long time – we’re talking years. For more severe issues, they may only be a temporary fix, lasting just a few months at most.
What Is the Cheapest Way to Fix a Head Gasket?
The cheapest way to fix a head gasket by far is to use a good head gasket sealer. You’re looking at $100 or less, compared to thousands of dollars if you took your vehicle to a garage for a replacement head gasket.
Are Head Gasket Sealers Just as Good as a New Head Gasket?
In short, no. Nothing will be better than replacing the head gasket at a garage. Having said that, head gasket sealers can almost be as good at just a fraction of the price, so they’re certainly worth considering.
Wrapping Up
We understand how frustrating a blown head gasket can be, especially if you can’t survive without your vehicle. Trying to find the right solution without it costing the earth can be tricky.
Thankfully, there are plenty of solid products on the market designed to fix blown head gaskets quickly and easily. These head gasket sealers cost just a fraction of the price of having a new head gasket installed, making them a very appealing option.
Regardless of the route or product you decide on, remember to never ignore the symptoms of a blown head gasket. If left untreated, it can very quickly ruin the engine and the repair costs can spiral out of control.
I am wondering where should you pour the Head Gasket Fix?
right into the radiator.
After using this, will the radiator need to be replaced?