How to Fix a Valve Cover Gasket Leak

In your vehicle’s engine, there should be 1 or 2 valves depending on if it’s a 4 cylinder, V6, or V8 engine. If the vehicle has a 4-cylinder engine, there should be 1 valve cover. If the vehicle has a v8 or v6 engine, there should be 2 valve covers on either side of the v. The valve cover is located on top of the cylinder head and it protects the valves. The valves are there to control the number of gases that are let in and out of the cylinder. The two valves – the inlet and exhaust valves are used for this purpose. The valves are opened and closed by an arm that’s moved by the camshaft lobs or the pushrods. This valve needs to be lubricated with oil to make sure it doesn’t wear down.

There should be no high-pressure oil around the valve because they should be drained through small holes in the back of the oil pan. Since there’s a lack of high-pressure oil located under the valve cover gasket, the valve cover gasket leak should be very slow. A squirting lead will indicate that the oil is running at high pressure that this isn’t good. Although the leak is most likely slow, isn’t important that you know what to do when the valve cover gasket is leaking. If the oil leaks into the exhaust manifold, this can cause a fire. If there’s a lead, your engine oil will run out soon and this causes wear on the engine which could ultimately lead to engine failure.

How to Identify Valve Cover Gasket Leak

It’s important that you know for sure you’re experiencing a valve gasket cover leak. If you misdiagnose this, it could be expensive so it’s important that you know what you’re looking for. Putting a lot of effort for it to not be a gasket leak is going to leak you very frustrated. The valve cover gasket is the highest seal in the engine so you shouldn’t miss it. You should be able to find evidence that there’s an oil leak – the leak should be followed until it disappears. You should notice the lead on the front or side of the engine and a flashlight will make this a lot easier.

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If there are things that are blocking the valve cover gasket, you should be able to move them out of the way. This might lead to you removing the throttle, intake manifold, or spark plug wires. Once you’re done looking for a leak, you should be able to inspect the valve cover for a few things.

You need to check for cracks in the valve cover that could cause it to lead. Check for any loose screws that could cause the valve cover to become loose. Check if any part of the gasket is poking out under the valve cover. Check for any residue of oil that could be on the/around the valve cover.

Once you’ve inspected the valve cover for damages that could cause a leak, you need to know how to move forward. If there are loose screws that have caused the valve cover to become loose, they’ll need to be tightened or replaced immediately. You’ll have to get a set of new screws that matches the previous and this will allow you to tighten the valve cover again. To ensure that it’s tight enough, you should use a torque wrench – make sure not to go too tight or you’ll risk breaking the valve cover. If the valve is creaked or broken, you’ll need to get it replaced (View on Amazon). You can also head to the dealership to get it replaced.

Signs of a Valve Cover Gasket Leak

If there’s a leak, there are a few signs that will let you know this. Using signs to find out about a damaged component can be tricky so there are a few simple things you can do. The quickest thing you can do to diagnose this is to use an OBD2 scanner tool. When there’s a problem in your vehicle, it gets sent to a diagnosis unit and a professional OBD2 scanner (View on Amazon) is able to diagnose this error code. Once you’ve connected the OBD2 scanner to under the steering wheel, it should send you the error code related to the valve cover gasket leak and it should tell you what the error code means.

Thrashing Noise – if you can head a thrashing noise in the bonnet, this could be a sign that there’s a lead. The intake and exhaust valves can open and close rapidly while the engine is running. This can cause problems under the valve cover and this rapid opening and closing can cause the oil to start leaking. If you’ve been driving for some time, the valve cover gasket can eventually dry out and crack. Because the valve cover gases seal the oil inside, if it cracks, then you’ve got yourself an oil lead. The crack might not be able to contain all the oil that’s flying around which will cause it to escape. This trashing about can also cause the covers bolts to become loose.

Burning Smell – if you can smell a burning smell, this is an indicator that the valve cover gasket is leaking. When oil leaks of the valve cover, it can come into contact with the exhaust and start to burn. This smoke can travel to the cabin and you’ll be able to smell it. The oil leaking from the valve cover can also travel down or the side of the engine and it can make it seem light there’s an oil leak somewhere else. To help you locate a leak coming from the valve cover gasket, you can use a telescoping mirror (View on Amazon) and a flashlight like mentioned before. You should be able to locate an oil trail but make sure the engine isn’t running whilst you’re doing this.

Check Engine Light – if the check engine light comes on, this could be a sign that there’s a valve cover gasket leak. The bad thing about using the check engine light as an indicator is that it can come on for pretty much any problem which can make it hard to narrow down as a gasket cover leak. If the check engine light is flashing, this will allow you to know that there’s a possibility it could be a valve cover gasket leak.

Check Oil Level – If oil is leaking, then you’ll be able to notice it by checking the dipstick level. If you’re leaking oil and you don’t notice this, it can cause wear on the engine if it’s running without. The last thing that you want for any engine is for it to wear down and shut down completely. Once the engine is gone, you may as well get a new vehicle. To check the oil level if your vehicle is modern, the oil light will remain low. If not, you can check the oil level on the dipstick. The dipstick will tell you that there isn’t enough oil on the dipstick.

If you continue to drive while there’s a valve cover leak, it can cause the leak to get worse. The action of the valvetrain moving while the engine is running will result in a bigger oil bath. More oil will start gushing out of the valve covert while the RPMs are increased. As soon as the RPMs start to drop, you’ll notice that the leak isn’t as intense.

How to Prevent Valve Gasket Leaks

To prevent valve gasket leaks, you need to make sure that you are performing routine maintenance steps on your vehicle. Routine maintenance can save you from experiencing problems with your vehicle and this is what’s needed to prevent them. Routine maintenance is like brushing your teeth, if you don’t do it, your teeth will start to decay over time. This is the save as a car, if you fail to maintain it, it’ll start to decay and experiencing problems – repairing these problems cost a lot of money and I’m sure you don’t want to that.

If you want to avoid valve cover gasket leaks or further problems with your car and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.

How to Fix Valve Cover Gasket Leaks

1. To fix the valve cover gasket leak, you need to you should check the valve cover bolts. You can lightly tap them using a torque wrench. Using the torque wrench, you should tighten the screw on the valve cover gasket. Make sure that you don’t try and tighten the valve – it won’t stop the gasket from leaking. If the bolts are made with aluminum, they can be more susceptible to cracking.

If they’re steel, they’re likely to become warped. If you inspected the valve cover and knew the problem was being caused by loose bolts, tightening then should do the trick. You should be able to close the bonnet and start driving again – make sure to monitor the oil level after doing this.

2. If you want to fix the valve cover gasket further, make sure to let the engine cool down below you remove the valve cover. If you’re not sure how to check it, you should look at the service manual for instructions. To remove the valve cover, you’ll need to remove the spark plug brackets, PCV hoses and throttle cables that could be blocking it. The valves bolts will also need to be unscrewed.

3. You should now remove the valve cover – using your torque wrench, lightly hitting the valve cover, and help to loosen its grip. As a caution, make sure not to lose the bolts in the midst of the engine as it’ll be more work to get out.

4. Once the valve gasket cover has been removed, you should not install a new one. You might need to scrap it to make it easier, do so but make sure not to use any metal scrapers on the valve cover of the cylinder head. Using plastic will do the best job here.

5. Once you’ve just the new valve cover ready; you can apply silicone (View on Amazon) when it needs to be applied. Before you do this, you should look at the service manual and it’ll tell you want you can use if you want to fit a new valve cover. Make sure that the surface of the valve cover is cleaned before you try to apply the silicone.

6. You can now install the valve cover and the new gasket by tightening the bolts.

Fixing the Leak with Oil

Another way you can stop the leak is by using a permanent seal (View on Amazon) to block the oil leak. This is a petroleum distillate that will help to seal any cracks that will help to prevent the leak. Using a valve cover gasket sealer is a quicker method to stop the gasket lead that getting the valve cover replaced yourself or heading to the dealership to get it replaced. This will keep the engine oil in and protect the engine from wear – failing to seal any cracks in the valve cover gasket can lead to engine wear which will harm your engine.