What Is a Valve Cover Gasket? (Symptoms + How to Replace)

07 Mar.,2024

 

When your engine starts burning oil along with gas, the signs are hard to miss. You may see smoke clouds when you start your vehicle, or your cabin could fill up with a weird burnt oil smell. 

Are you experiencing these signs too? 
Chances are that your engine might have a leaky valve cover gasket

But what’s a valve cover gasket? 
And how to spot one that’s failing? 

Fret not!
In this article, we’ll cover everything about valve cover gaskets, including what’s a valve cover gasket, signs of a failing cover gasket, replacement steps, and cost. 

This Article Contains: 

Let’s begin. 

What Is a Valve Cover Gasket?

The valve cover gasket is typically made of rubber, plastic, or cork. It’s an important engine component that prevents oil from escaping the engine block. Not to be confused with the head gasket, which seals off the cylinder head hardware from the engine block, the cover gasket seals the valve cover and the engine body. 

But why does engine oil leak out? 

Your engine’s valve train opens and closes rapidly while your vehicle runs. This creates considerable mechanical action, requiring a hot oil shower for lubricating critical combustion parts. 

The valve cover gasket is positioned between the engine and the valve cover to seal the oil inside. However, like other engine parts, the cover gasket can dry out or crack, losing its ability to contain the engine oil. 

A leaky valve cover gasket can allow debris and small particles to settle between the pistons and cylinder, causing wear and tear. A low engine oil level could also cause metal components to grind against each other, shortening your engine’s lifespan. 

So, how do you know your cover gasket needs replacing? 
Let’s get a clear picture of how a bad valve cover gasket looks.

3 Revealing Signs of a Valve Cover Gasket Leak

The cover gasket is an engine component that prevents engine oil from leaking out, and if it starts to fail, oil starts to leak.

But how?

Engine oil is an acidic lubricant that can slowly eat away at the rubber gasket. When that happens, you’ll end up with a faulty valve cover gasket, and an engine oil leak. The oil leak spreads to other engine parts and could cause severe engine damage.

To prevent expensive repairs, here are some of the leaking valve cover signs that you should watch out for: 

A. Low Engine Oil

If you notice the “Low Oil” light illuminated on your dashboard, you should look for a leaking valve cover before checking out other possible causes. 

A bad valve cover gasket will allow engine oil to escape and leak out of the engine. Having a low engine oil level could create friction between the engine components. This, in turn, will cause the engine temperature to rise quickly, leading to engine failure and possibly, even fires. 

B. Burning Smell

The oil leak can drip onto other extremely hot engine parts, such as the fuel intake or cylinder head. This burning oil will give off a strong odor or cause excessive smoke in the exhaust when the engine is running. 

C. Rough-Running Engine

Sometimes engine oil leakage can make its way up to a spark plug, leading to a misfire or causing severe engine damage. You may also hear strange sounds when you hit the throttle. 

In worst cases, a spark plug may ignite the engine oil, causing your vehicle to catch fire. 

If you suspect any of the signs above, you’ll have to get your car towed to a repair shop or get a mobile mechanic to drop by and have a look. 

Now, let’s go over how to replace a damaged valve cover gasket.  

How to Replace a Valve Cover Gasket? (General Guidelines)

Here’s a general guideline on valve cover gasket replacement

Note: Always let a professional mechanic handle any repair task if you’re unfamiliar with engine parts.

1. Tighten the gasket first: Sometimes, engine vibrations can loosen the gasket over time, causing the oil to escape. Before getting a new valve cover gasket set, use a torque wrench to tighten the cover gasket bolt to the manufacturer’s specifications. 

2. Allow the engine to cool off: If tightening the gasket doesn’t stop the oil leakage, allow the engine to cool off before accessing the rubber valve cover. Some vehicles may require you to remove the plumbing first. You may also need to remove the PCV hoses, spark plug tubes, brackets, and throttle cables. 

3. Lift off the valve cover: Remove the valve cover bolts and lift the cover. If it doesn’t budge, gently tap it with a rubber mallet. Cover your engine with a rag to prevent dropping off any bolt into the internal compartment. 

4. Replace the old gasket and fit the new gasket: Pry off the old gasket with your hands or use a plastic or silicone gasket scraper. Avoid using a metal gasket scraper to remove the gasket material if you have an aluminum valve cover or cylinder head, as it could damage the unit. 

5. Apply silicone (only if recommended by the manufacturer) onto the new gasket: If your service manual asks you to apply silicone, first clear the surface of the valve cover from debris and sludge with a brake cleaner. Apply the silicone and leave it to cure before firing up your engine. 

6. Re-install the valve cover: Once the new valve cover gasket is in place, re-install the valve cover and tighten the valve cover bolts with a torque wrench.

Wondering how much it’ll cost to get the cover gasket replaced by a mechanic?
Let’s find out.  

How Much Does a Valve Cover Gasket Replacement Cost? 

On average, a valve cover gasket repair job costs between $110 – $340, depending on the make and model of your vehicle. 

Rubber valve cover gaskets are generally inexpensive, costing $10 to $40. But the labor charges could set you back by $70 to $300

Even though replacing valve cover gaskets is a fairly straightforward job, some vehicles may require removing other engine components, which means additional labor. 

For example, a V6 engine may require removing the intake manifold to access the rear valve cover. In that case, the replacement cost could escalate to $250-$330 for labor charges plus $25-$85 for a valve cover gasket set. 

Now, you may want to know how safe it is to drive with a faulty valve cover gasket before getting a replacement.

Is It Safe to Drive With a Leaking Valve Cover Gasket

A valve cover leakage isn’t a fault that’ll leave you stranded on the road. 
Yet, it’s not an auto repair that you should neglect for long.

The urgency to replace a valve cover gasket depends on how bad the leak is. 

Certain high-mileage cars may have some “sweating” around the valve cover. If the oil leakage isn’t too much or if there’s no burnt oil smell, it isn’t a big issue. But, if you can smell burnt oil from under the hood, oil vapors have likely entered the air you’re breathing, which is a health hazard. 

Hot leaking oil could also damage other car parts, like a spark plug or the drive belt, and even cause misfires or engine failure. So if you suspect a gasket leak, don’t delay a valve cover gasket repair.

Wrapping Up 

Valve cover gaskets are vital for protecting cylinder head hardware and preventing the engine oil from escaping the engine. So when it comes to replacing the valve cover gasket and accessing critical engine parts, it’s best to have an experienced mechanic perform the repair for you. 

That’s where AutoNation Mobile Service steps in. 

With AutoNation Mobile Service, you get:

  • Convenient, online booking for every auto repair and maintenance service
  • Competitive and upfront pricing
  • Expert technicians who perform vehicle inspection, repair, and maintenance
  • A 12-month | 12,000-mile warranty on all auto repairs

Contact us, and our mechanics will drop by to quickly perform a valve cover gasket replacement or other services like an oil change right in your driveway!