When do head gaskets go

Because the head gasket is seated at the centre of your engine, the work needed to disassemble and reassemble the engine alone can take up to and over 10 hours — so you can see why a head gasket replacement would be so pricey. In some cases, you might be able to repair a head gasket.

Our sister brand, Holts, produces a professional cooling system leak repair called Wondarweld , which is designed to seal cracks in the head gasket, cylinder heads and engine blocks, for a permanent repair.

Head gaskets typically last , miles, which is considered about the lifetime of most cars. That means, if you look after your car and follow the service schedule, you should never be faced with a blown head gasket. For more how-to guides and motoring features, take a look at the Prestone blog , or for our complete range of engine additives and fuel system cleaners, visit the homepage today. What is a Blown Head Gasket? A few dollars of prevention is much better than the several thousand dollar cure when it comes to head gaskets.

The replacement head gasket itself is not expensive, but the repair is very labor intensive, which significantly increases the cost of repair, especially on modern cars. Head gasket failures are usually caused by repeated overheating or continuing to drive after the car has overheated, so the best way to prevent a head gasket failure is to ensure your cooling system is in good condition.

And if your vehicle does start to boil over, stop, let it cool for at least an hour, and refill the radiator before continuing. Checking the cooling system is easy: Ensure there are no leaks, that the radiator is working efficiently, the thermostat opens properly, and the coolant is topped up to the correct level.

Also make sure the fan mechanical or electric is working, has all of its blades, and has a shroud around it to increase the efficiency. If you suspect a head gasket failure, the scientific test is to check for combustion gasses in the cooling system.

This test will show if the compression has leaked into the cooling system, and therefore if the head gasket has blown. The old mechanic's trick is to take off the radiator cap, start the car, and look for bubbles in the coolant. However, these will not show if there are any other failure spots in with the head gasket, so the absence of gasses in the cooling system does not guarantee a healthy head gasket. Some older head gaskets can just fail because they are of a poor design, and are not robust enough for the application.

This used to be more of an issue with older style, metal gaskets, which could only last for so many years of going from cold to hot with every startup before an inevitable failure. Thankfully modern MLS multiple layer steel replacement gaskets are now available for most applications, and offer improved reliability over the original gasket design.

Go to front page. Overheating is another possible cause, as the gasket is placed under conditions over and above its design criteria, resulting in warping and permanent damage.

This can be purely down to coolant leaks from a corroded radiator or dodgy piping, or it could be pre-existing failures in the head gasket. Another sub-section of overheating is the way in which your engine warms up.

The gaskets within an engine are specifically designed to contain thermal properties that allow them to expand and contract as the engine warms up and cools down respectively. Hopefully as petrolheads you all know that you should wait for the engine to warm up fully before putting the foot down.

I personally keep my engine speed below rpm before my temperature gauge is nice and stable. But over-rev while cold and the engine and head gasket will be put under extreme thermal stresses as it expands too quickly, which can result in gasket failure as well as cracks in the head itself. Poor gasket design can also be a car killer. The K-Series engine was revolutionary in its design, using a sand cast which had liquid aluminium poured into it. One of the more subtle signs of a blown head gasket is discolored fluid.

Your head gasket's job is to stop fluids in your engine from mixing. Discoloration may not be common, but it's a surefire sign that this component has failed and things are mixing where they shouldn't be. Your engine oil serves a very important process and, if it stops working, it can lead to grinding pistons and various other complications. This presents a problem when your head gasket blows, as it can lead to both your oil and coolant mixing in different ways.

Oil that has been contaminated with coolant will foam up. It's not usually very subtle, either. Imagine the foam off of cappuccino and it's in your valve cover. Not ideal and a definite problem as it impedes your oil's ability to do its work, properly. When coolant has oil introduced into it, it forms a thick, white film. It can be upsetting to discover, but it resembles mayonnaise and is found in radiator caps or, sometimes, in overflow reservoirs.

This change in the oil's texture makes it much less efficient at lubricating your engine. This will quickly lead to quicker wear on your engine components.

Worried you may have a blown head gasket? Found your vehicle on today's list? Take your time to fully diagnose the issue, whether on your own or with the help of a mechanic. Consider dry and wet compression tests, or a cylinder leak test in order to pinpoint the exact location of your leak.

A block tester is also a good idea in order to determine the presence of any combustion gases in the cooling system. Not only is this safe, but it's a useful yardstick by which to gauge head gasket failure. Ultimately, for many of you, you'll want to call your trusted mechanic, ask for a blown head gasket cost breakdown, and make a decision as soon as possible.

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