Tapping, clicking, ticking, rattling, knocking — whatever you may call it, it’s something you do not want to hear coming from your engine. What is engine tapping? A clicking or tapping sound coming from your engine that gets louder as you crank the engine is most likely “tappet” or upper valvetrain noise, which can be caused by a number of issues including low oil pressure, excessive valve lash, or worn or damaged parts. It could mean a number of things that will not always be easy to diagnose. Fortunately, it could be a simple problem you can fix yourself so it’s best to really know what is engine tapping, because you’ll never know you may not need to go to a mechanic and do the repair yourself. We will learn all about what is engine tapping in this article.
What causes tapping?
If you want to know how to remedy engine tapping, you must first figure out what's causing it. What causes the ‘tappety' engine noise, which is both annoying and potentially dangerous? In the automotive industry, the definition of tappets might be a little ambiguous. The annoying ticking noise is commonly referred to as “engine tappets.” This is somewhat incorrect, as engine noise can be created by a wide range of valvetrain components.
Although a problem with the tappets or cam lifter could produce the tapping sound coming from the engine's head, it could also be a problem with the camshaft, valves, rocker arms, or even a lack of lubrication.
What is engine tapping? Engine tapping sounds are frequently caused by low oil pressure. When engine components aren't getting enough lubrication, the sound is made. You either forgot to replenish your oil, need to change your oil or filter, or there's a problem inside the engine producing the low oil pressure.
To begin, check the engine dipstick for a low oil level. If the oil level is low, add enough to bring it back to the full mark. Is the engine still making a racket? Make sure your oil pressure is correct. A low gauge reading (or oil warning light) indicates that there is a major internal engine problem preventing normal oil pressure from reaching the upper valve train components. A worn or damaged oil pump, a clogged oil pump pickup screen, or a clogged oil filter could all be to blame. Using too thick a viscosity of motor oil in cold weather can also cause noise and wear by slowing the flow of oil to the upper valvetrain.
Malfunctioning valve lifters, as well as an exhaust manifold leak, are the most prevalent reasons for engine tapping. The issue is most probably exhaust manifold leak if the noise lasts more than a minute and completely disappears or fades once the engine has warmed up. However, if the noise lasts only a few seconds, it could be a valve lifter issue. To check, visually inspect the exhaust system for leaking gaskets or cracks in the exhaust manifolds.
Black soot stains where the exhaust manifold joins to the cylinder head indicate an exhaust manifold gasket leak. Look for any broken bolts in the exhaust manifold. Check for gaskets where the manifold connects to the exhaust pipe. It's important to keep in mind that the exhaust system heats up quickly. Exercise caution when working with hot or moving engine parts. Before removing any exhaust system fasteners, spray them with a penetrating lubricant. The nuts and bolts will be easier to disassemble and less prone to break as a result.
If there are no signs of an exhaust leak and the noise goes away after a few seconds of driving, it could be an oil control or valve lifter problem. The tapping, ticking, or clicking sounds can also be caused by worn or malfunctioning valve train components such as lifters or cam followers, as previously discussed.
A tappet lies on the end of a pushrod or rocker arm. When the cam profile swings around its own axis, and the other end interacts with the lobes of the crankshaft, it causes the valve to opffen and close. Because they ‘lift' the rocker arm of an OHC engine, the tappets are known as ‘lifters.' A locking screw on the connection to the rocker arm can raise or decrease the amount of lift that the tappet allows from the camshaft, allowing the amount of valve lift to be changed this way.
As the camshaft spins and the lobes rise and then lower the tappets as engine oil acquires dirt and viscosity increases, the contact between them wears both components down to the point where an audible noise can be heard between them. Oil starvation can also affect the rest of the valvetrain, causing rocker arms, pushrods, and valves to clang about the engine due to a lack of lubrication.
This wear and tear can result in an annoying tapping noise as well as a decrease in engine efficiency and hence power. A valve will not open to its predetermined lift distance due to a worn camshaft or tappet, inhibiting the air/fuel mixture that is trying to rush into the cylinders.
You should start working on how to correct engine tapping as soon as possible because, in extreme cases when this problem has been overlooked for thousands of kilometers, the lack of lubrication can cause costly damage to valve train components, with the camshaft being the most expensive.
A tappety engine can also be caused by improperly tuned tappets. Because the tappet no longer has continuous touch with either the pushrod/rocker arm or the camshaft, excessively spaced tappets cause the engine to rattle. When the engine warms up, the valve stem expands thermally, demanding additional space to handle this expansion. This is why, once the engine has cooled down, valve adjustment should be done as quickly as feasible.
If the tappet adjustment is overly tight, the valves may stay open for longer than they were designed to, resulting in valve chips and cracks. Self-diagnosis might be difficult due to a variety of factors that could be at play.
What does it mean when the valves are tapping?
What is engine tapping? It could be tapping the valves that are tapping. Excessive clearance between two internal engine elements is the most common cause of valve train noise. A valve spring is used to return each valve to its original closed state. Because of the additional clearance, if a valve spring breaks or a camshaft lobe wears out, the engine will make a tapping or clicking sound.
One of the most prevalent valve train noises is a clicking lifter. Fixing this normally necessitates an adjustment if the engine is fitted with solid (mechanical) lifters. However, not every noisy valve train is caused by a misalignment. As a result, even after the valves have been properly set, the engine may still be noisy. If this is the case, the valve lash is not the source of the problem. The sound, on the other hand, is most often the result of a mechanical failure due to wear.
The valve lifter is frequently the source of noise, despite the fact that there are many other possibilities. Another cause of valve train noise in any hydraulic application is machining of the cylinder head and valve seats. As a result, the shape of the rocker arm alters.
Many mechanics believe that malfunctioning hydraulic lifters are to blame. That is not the case. The lifter is merely reacting to the circumstances and attempting to adapt to them. That's why it's crucial to rule out the valve train as the source of the problem.
The weight of the oil or the oil supply itself is usually the cause of the sound throughout the valve train. Foaming and aeration will occur if there is too much oil in the crankcase. When air enters the lifters, they will stop working properly. Valve train noise can also be caused by a lack of oil delivery to the lifters.
This could be due to a lack of oil in the crankcase, a malfunctioning oil pump, or plugged main oil gallery lines. When cold-starting an engine, excessively thick engine oil will generate complete valve train noise. When the oil heats up and begins to flow correctly, the noise will decrease. As a result, in the winter, an engine with thick oil will be more prone to noise than in the summer.
How do you get rid of engine ticking?
What is engine tapping? Or ticking and how do you get rid of it? Before we discuss how to get rid of engine ticking you must understand that there are normal instances when an engine could produce a ticking noise. For instance, it’s normal for an engine's purge valve to release stored gasses into the engine’s intake system where that stored gasses are burnt up. And when this happens it can create a normal ticking noise. By recommendation, the PCV valve should be changed from time to time as it can emit a ticking sound. Another normal ticking noise can be produced by the car’s fuel injectors.
The initial step to be taken is looking into your oil’s, as this may be just the thing you need to fix to resolve the issue. The wrong oil will not give the right lubrication for what the many moving elements in the valvetrain were built for. Not enough or too much viscosity than what is required would result in loud metal-on-metal contact due to lack of lubrication. So using the proper oil grading for your engine is a must.
Simply changing your oil will help eliminate the tapping sound, since an engine that has been neglected for a long time can begin to clog up its oil filters, resulting in debris and filth building up. You can also benefit from using oil additives to clean rockers, valves, and tappets without affecting viscosity of the oil.
The hundreds of parts interacting with each other within the valvetrain must be suitably lubricated to minimize unwanted contact and noises. If these changes have no effect on the tappet noises, a full tappet correction should be performed next.
By wedgeing a feeler gauge between a rocker arm and the valve stem and adjusting the valve adjustment screw to the correct clearance using a workshop handbook, a factory setting can be found. Expect to pay a lot of money for tappet, valve, and maybe camshaft replacements if your engine still rattles after the adjustment.
Engine tapping can be one of the most annoying aspects of owning an older vehicle, and while they may appear to be nothing more than an inconvenience at first, if you care about your powertrain, you should address them as soon as possible.
Given how simple most of the repairs for these annoying rattles are, regular maintenance checks should ensure that you and your car enjoy many years of trouble-free driving. But now you know what to watch for if your engine starts to rattle again.
What do bad lifters sound like?
What is engine tapping? It could also equate to having bad lifters. Hydraulic lifters having issues would usually make a tapping noise rather than a knock or ping. Depending on the nature of the hydraulic lifter problem, the tapping will be rapid and may occur while the vehicle is cold or hot.
If your car's hydraulic lifter is malfunctioning, replace it as soon as possible to avoid further engine damage. A defective hydraulic lifter will almost always need to be replaced. Depending on the make and type of your car, you may be able to get away with changing just one damaged hydraulic filter. Many mechanics, however, advise that if you replace one lifter, you should replace them all because it's usually a sign that the others will fail soon.
Depending on how old your car is, you might want to consider using remanufactured lifters rather than buying new ones. For older used automobiles that may not have many more years of service left in them, refurbished hydraulic lifters will cost a lot less money and will typically do an adequate job.
What is engine tapping? It is a noise you don’t want to hear coming from the engine. The cause could be resolved with a simple fix or it may be caused by something more alarming. The most important thing is to have it checked right away before only an expensive fix can resolve it.