Symptoms of Bad Valve Seals: Is There a Quick Fix?

Sometimes, the smallest parts prove to be the most important ones for a car to work properly, and that’s the case with valves. These little moving parts sit in the engine’s head or heads and regulate the amount of fuel to air mixture. As such, it’s important to always keep them in check to ensure that your car’s engine works properly and efficiently.

To keep oil from pouring down the valve cover and into the engine cylinders, valves have rubber seals that wear from use and require regular checkups. But, how to know if your valve seals are in order? I’ll give you the most common symptoms of bad valve seals and some tips on how to sort out this common issue.

You might have noticed some of these symptoms yourself. If you keep track of how your car drives, what sounds it makes, and what smoke it puffs out, you’ll see and experience some changes. But if you don’t know what they mean, it’s time to learn and return your car to its maximum capacity and optimal working order.

Symptoms of bad valve seals. How to fix the problem.

Symptoms of Bad Valve Seals

Luckily, the symptoms of bad valve covers are unique to this issue and easy to identify. So you’ll be able to diagnose it quickly and on time.

Ticking Noise

This is the first sign of deteriorating valve seals, but it’s not so easy to point it out if you are not paying attention to every noise your car makes. The ticking noise will get louder as you accelerate, but you will hear the same type of noise even when the car is idling.

The ticking noise comes from misalignment or wearing out of the elements of the valve train system. Excessive movement in the valve train will change the sound of your engine at any RPM. And if you’re lucky or skilled enough to notice these subtle changes, you’ll be able to diagnose a valve seat issue before it gets worse.

Smoke Coming From the Exhaust

Every car has some sort of smoke coming from the exhaust pipe. However, if it is thick and light blue or light grey, it’s a clear and the most obvious sign of bad valve seals. A change in exhaust smoke color indicates that the engine is burning oil because worn valve seals are letting it go into the combustion chambers.

This symptom will be easier to notice during urban commutes because of constant stopping and acceleration. On highways or other open roads, it will be much harder to see the smoke due to the constant RPM of your engine.

If you’re having doubts that your engine is burning oil, the best way to check is right after a cold start. When you cold start your car, all residual oil built up in the cylinder head will be sucked into the combustion chamber and burn. That will result in a cloud of colored smoke, and that will be one of the most certain steps towards diagnosing the fault in the valve system.

Also, the more smoke your car is emitting, the worse the condition it is. As a faulty valve seal deteriorates more over time and with each drive, your car will use up and burn more and more oil, thus the smoke levels and density will increase if you don’t act quickly.

Excessive Oil Consumption

Next, there’s the oil consumption. As your car is now burning oil, you’ll also notice that the oil level decreases much faster than it should be. By this point, it’s time to act fast because the lack of oil can cause permanent damage to the engine, and that’s something you want to avoid at all costs because it will significantly rack up the repair bills.

Since you’ll be checking the oil level, you could also check for oil residue on the engine’s head too. Apart from burning oil, faulty valve seals will leave residual oil somewhere on the engine. So, while the hood is open, you should check under the valve cover for any oil residue.

Lack of oil inside of the engine and excess of it outside are another set of clear signs that your valves might be compromised.

Decreased Compression and Weak Acceleration

Healthy valve seals keep the compression of the engine in factory spec, while broken or used up ones will decrease it. That will directly result in loss of engine power, thus acceleration figures as well.

If you see your car struggling to achieve higher speeds, it’s time to see the mechanic. They will further diagnose the fault and will help you with the issue.

How to Fix Bad Valve Seals

In all honesty, there’s no long-lasting quick fix to this issue. There’s basically no way to bypass bad valve seals and continue driving your car on a DIY budget.

Fortunately , there are some first aid kits, but its efficiency truly depends on the general condition of your car’s engine and the extent of damage to the valve seals.

Oil Stop-Leak

This additive can be found quite easily, and it’s designed to extend the lifespan of valve seals. It causes the valve seal rubber to swell, which will temporarily reduce oil leaks. However, you shouldn’t rely on this additive for long, since its effects are temporary.

Also, if the valve seat is badly worn out, cracked, or damaged, oil stop-leak will have little to no effects, and you won’t notice any change or decreased symptoms mentioned above.

If you decide to use oil stop-leak, you’ll be happy to know that it’s an easy temporary fix. You simply pour it into the oil filler tube, just like you’d pour motor oil.

High Mileage Oil

If your car has passed the 75.000-mile mark, you should consider using a special kind of motor oil designed to help the aging valves remain in good health.

As previously mentioned, valve seals are made out of high-quality, high-density rubber. As time and miles pass, the rubber gets less elastic. As such, it is more prone to deterioration and cracking. High mileage oil has additives that keep the valve seals pliable and soft which will extend their lifespan.

Using high mileage oil is also a temporary fix to the broken valve seal issue, but its effect lasts longer than oil stop-leak. In the longer run, you’ll have more chances to preserve your engine by using this special oil, but this also isn’t the final solution to the problem.

Valve Seat Rebuild

Finally, the only option that will sort this issue out completely is the rebuild of the valve train system. The price of this procedure depends on age and brand of your car, but also the seriousness of the issue. Generally speaking, you’re looking at low four-figure sums, but some rebuilds will cost south of $1000 mark.

The reason for such a high price lays in the fact that the procedure involves disassembling the whole engine and removing the cylinder head cover, the spark plugs, pushrods, and rocker arms. If your car’s engine is a V6 or a V8, the procedure is even more complicated since a mechanic needs to diagnose which head holds the faulty valve seat.

At this point, you should take the worth of your car into consideration. The cost of the repair will surpass the price of your daily beater, whereas your beloved car might lose value if something goes terribly wrong.

Can You Prevent Faulty Valve Seals?

Sadly, there’s no way to prevent faults in the valve train systems. As with many other aspects of owning a car, regular maintenance is the key to your automobile’s wellbeing and longevity.

Using adequate motor oil for a high mileage car is a way to keep the valve seat elastic for longer. Eventually, you’ll be looking at the inevitable – taking your car to the mechanic for valve train rebuild.

Diagnosing broken valve seals is easy, and isolating the issue can save your engine and keep your beloved car running for many carefree miles.




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