Head gasket sealer is a product that's supposed to temporarily fix a leaking head gasket. It works by plugging the tiny holes in your engine's cylinder head and restoring compression.
When done correctly, this can get you back on the road for a few thousand miles until you can get into your mechanic's shop for a complete repair job.
But does the head gasket sealer work? The short answer is yes. Head gasket sealers can temporarily fix a leaking head gasket, but they're not a permanent solution.
These products last a little while and can only do so much; eventually, the wear and tear will need to be dealt with for your car to run properly again.
A head gasket serves the critical purpose of sealing the engine block from the cylinder head to prevent the oil and coolant from mixing. In addition to obstructing these fluids from contaminating each other, the head gasket prevents overheating and enables the engine to produce the proper amount of compression to function efficiently.
The sealer is a liquid that goes into your engine and plugs up the holes in your head gasket. It's like pouring concrete over a crack in a sidewalk, except with less mess.
The idea behind head gasket sealer is that it can help stop oil leaks inside the engine by plugging up small holes in the head gasket.
Although head gasket sealer can save you from having to replace your whole engine, it is not without drawbacks.
Considering head gasket replacement ranges in price from $1,000 to $3,000, prolonging the life of your current head gasket is best for your wallet. In addition to regularly checking your oil, promptly addressing engine concerns, and maintaining appropriate engine coolant levels, a head gasket sealer can give you more miles out of your head gasket. For the sealer alone, plan to spend about $15 to $70. Even if the sealer is only leveraged to buy you time, it is a small investment to enable you to conduct your due diligence in getting replacement estimates before you’re stuck on the side of the road in an emergency.
No matter how nifty a product is, it has its unique pros and cons, and the sealer is no exception. By and large, it has the following benefits:
But as there are pros, there are also cons, which are as follows:
One broken circuit is enough for the engine to fail quickly. Determining the issue is sometimes tricky because it develops gradually, and the compression may remain the same. The following are symptoms of a failing head gasket.
An overheating engine and low coolant level could reveal a faulty head gasket. If the head gasket does not properly seal the oil and coolant from one another, then the two fluids mix, causing overheating. When checking your engine oil, if it appears milky, then the coolant has likely mixed with the oil.
Another indicator of a faulty head gasket is the color of the smoke from the tailpipe. If you notice blue smoke, there could be a loss of oil, while white smoke implies a punctured cooling circuit has caused engine coolant to leak into the combustion chamber.
Bubbles in the radiator while the engine is running are also symptoms of head gasket issues as it is a sign that combustion gasses are leaking into the cooling system.
Other signs of gasket issues include reduced engine performance exemplified by decreased power, rough idling, and diminished fuel economy.
When using a head gasket sealer, it is crucial to follow the instructions on the container. Ideally, you should mix this product with water in a bucket before applying it to the head gasket.
The percentage of water that you use depends on how much total surface area needs to be covered. For example, if you have just one small leak or crack in your cylinder head gasket, then only a small amount of sealer is needed.
In most cases, though, more than one square foot of surface area must be sealed. Therefore, mixing a larger batch can make this task easier for you and ensure that the job is completed quickly and efficiently.
Once mixed as instructed on the container's label, apply the mixture evenly over both sides of each valve cover plate where its respective internal gaskets meet.
Head gasket sealers are an excellent tool for plugging the holes in a damaged head gasket. They won’t fix the damage, but they can certainly buy you some time to complete the repairs.
If your engine is running hot or leaking coolant, it's worth trying this product before you go ahead and spend money on an expensive repair job.
And even if you successfully fix the leaking issue with the sealer, it’s still a good idea to let the mechanic inspect and, if possible, replace your gasket. This way, you’ll ensure your peace of mind.
Matt Yantakosol is a lifelong automotive enthusiast and former consultant focused on the consumer aspect of the industry. He has traveled to New York, Detroit, Chicago, L.A., Paris, Geneva, Frankfurt, and Tokyo Auto Shows to track and observe the newest industry innovations. In addition to JDPower.com, Matt's writing has appeared on Pcarmarket.com.
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