Have you ever heard ticking or tapping from your vehicle’s engine bay? If yes, then you have already dealt with lifter ticking. This noise is often caused by plugged valve filters failing to properly open and close the engine valves. And no — it is not to be confused with rod knocking or some other unusual sound.
Valve lifters (a.k.a. camshaft followers) produce a lift tick noise whenever one or more relevant components are compromised. These include grubby engine oil, defective pushrods, and misaligned timing chains (to name a few). For a more comprehensive enumeration, refer to the list of causes below:
- Worn, loose, or damaged lifters
- Oil-related problems
- Flawed camshaft system
- Bent or worn pushrods
- Mismatched valve timing
- Damaged or worn-out timing chain
- Rocker arm wear and tear
- Incorrect lifter spacing
- Engine overheating
- Carbon buildup
This article covers the causes of a lifter tick, its symptoms, and how to prevent it. We will also delve into the different valve lifters used in vehicles.
By understanding the causes and other proponents of this predicament, you will leave this page with a better working knowledge of maintaining a smooth-running engine while keeping potentially serious problems at bay.
What Is a Lifter Tick Sound?
As its name implies, a lifter tick sound is a tapping or “ticking” noise in a vehicle’s engine. It is often caused by problematic valve lifters that open and close the engine valves.
These lifters consist of a small piston riding inside a cylinder and a hydraulic plunger helping maintain proper valve lash or clearance. And because engine oil flows through them, they should ideally not stick or malfunction.
What Causes a Lifter to Tick?
Perfectly functioning hydraulic valve lifters are not always the case, though. Deterrents to ideal operation can be caused by dirt buildup or wear due to age.
When left undetected, the malfunction can result in a gap between the valve lifters and pushrod or rocker arm (which can potentially escalate into more serious problems). Other known triggers of this engine noise can be seen below:
1. Worn, loose, or damaged lifters
Flawed valve filters are arguably the #1 cause of lifter tick. There are three primary culprits behind this occurrence — heat, worn seals, and out-of-spec oil pressure.
Excessive heat causes premature lifter failure. Worn seals instigate leaks and eventual component damage. And an overly high or low oil pressure causes the valve filters to get over-pressurized (resulting in the valves not closing all the way).
Any one of these scenarios renders valve lifters dysfunctional. And until they are aptly addressed, you can expect your pushrod to bend and be displaced (among other consequences).
Naturally, the outcome would differ based on the lifter — hence, knowing which valve lifter you have is crucial. Below are the six types of valve lifters currently used in vehicles:
Oil pressure is utilized by these lifters to uphold the connection between the camshaft and valvetrain, accomplished through an inner piston that condenses under oil pressure and enables the lifter to remain in contact with the camshaft.
Unlike hydraulic variants, they do not have an internal piston — meaning they rely on a predetermined clearance or valve lash between the lifter and the camshaft to maintain contact. The valve lash requires periodic adjustment to keep within spec.
They are widely utilized in performance-oriented engines and vehicles like muscle cars, racing vehicles, and high-powered trucks due to their durability and superior performance (particularly in high-stress applications). A small roller bearing at the tip rolls along the camshaft instead of sliding it — effectively reducing friction and wear on both the camshaft and lifter.
Typically found in older vehicles, this type of valve lifter has a convex shape on one end and operates by sliding against the camshaft (as opposed to rolling along, as is the case with roller lifters). They are also more cost-effective to manufacture versus other valve types and can work with a wider range of camshaft profiles and applications.
Flat tappet (a.k.a. flat-face) lifters
Flat-face lifters are, perhaps, the easiest to weed out of all valve lifters. This is due to their flat contact surface that slides along the camshaft lobes to operate the valves. They are also less expensive to manufacture. The clincher? Performance capabilities are limited due to increased wear and friction.
Hydraulic roller lifters
This is the only hybrid valve type out of all lifters. Structure-wise, they are similar to hydraulic lifters but with a roller wheel reducing friction and wear on the camshaft and lifter. Because of their improved anti-friction capabilities, they are fitted in vehicles used for NASCAR, motorsport, and drag racing (in addition to heavy-duty and high-torque applications).
2. Oil-related problems
Oil-related problems are often associated with engine noises like lifter tick because the engine relies on oil to lubricate moving parts and prevent metal-to-metal contact. If the oil becomes impure or filled with particles, it cannot perform its lubricating duties.
Having a multigrade-oil-engine- mismatch can likewise have adverse effects on lubrication. Some layouts (for example, OHC engines) require viscosity grades that can travel farther vertically through passages and galleries.
Consequently, engine components can become damaged or worn — eventually producing that ticking sound most of us are too familiar with. Here are other things that could go wrong by deliberately using subpar engine oil:
- Low oil pressure
- Degraded or contaminated oil
- Incorrect oil viscosity or type
- Insufficient or incorrect lubrication
- Clogged oil passages
- Filthy or damaged oil filters and screens
- Faulty oil pump
Thankfully, regular inspection, oil changes, and high-quality oil and oil filters can help prevent the above problems by a huge margin.
3. Flawed camshaft system
The camshaft is a critical component of the valvetrain system that handles opening and closing the engine valves. It is also responsible for actuating the lifters that transfer the motion to the pushrods and rocker arms. Camshaft lobes and bearings are equally important, as these parts in poor condition can lead to damage, premature acceleration, or uneven wear.
4. Bent or worn pushrods
The pushrod is the 1st of 3 parts responsible for transferring motion or lift from one area to another within the engine. It works alongside the camshaft and the rocker arms and, in a way, is dependent on good-quality lifters and these two other components for optimal operation. When compromised, it is likely to cause valve lifters to tap against the camshaft, which produces the lifter tick sound.
5. Mismatched valve timing
While the cams are predominantly responsible for air intake and exhaust timing in a power mill, this feat will be impossible without working valve springs and proper valve adjustment. The springs control the movement of the valves and maintain contact between the camshaft and the valvetrain. Meanwhile, valve adjustment dictates whether or not lifters get partially compressed.
If the valve springs are broken or the valves are not well-adjusted, the lifter will lose contact with the camshaft — resulting in a lifter tick sound.
6. Damaged or worn-out timing chain
Although the timing chain is closely associated with valve timing, I chose to enlist this separately since the route of a damaged or worn timing chain can go several ways. As such, the potential problem that follows next is largely contingent on the severity of damage incurred.
For instance, a loose chain can lead to improper valve lift and a lifter tick. In like manner, a worn chain can cause uneven rotation of the camshaft and, eventually, uneven valve lifter wear. However, there are cases where these similar situations result in a more catastrophic engine failure. When this occurs, it is usually because of prolonged neglect.
Essentially, the timing chain is responsible for synchronizing the camshaft and crankshaft movement. Should the chain become damaged or worn, it will naturally cause the camshaft to move out of synch or position — leading to a lifter tick.
7. Incorrect lifter spacing
Sometimes, a lifter tick is not caused by engine oil issues but by lifter adjustment. The valve lifter sits between the pushrod and the camshaft. If there is too much space between these parts, lifter ticking may result.
Conversely, if the lifter is too tight, it can cause problems with the engine’s function since the former would not have the space to accommodate the stem expansion of a heated power mill.
If such is the case, a mechanic should check lifter spacing to prevent future engine failure. However, feel free to take on the task if you are mechanically savvy.
8. Engine overheating
Overheating can cause several problems in the engine, including a lifter tick. This is because when the heart of your vehicle overheats, the oil inside it can break down and become less effective at lubricating critical engine components.
Overheating causes seal/gasket damage and distortion or warping of engine parts (including your cams and valve lifters), resulting in improper valve timing and lifter tick noises (among other things).
9. Rocker arm wear and tear
Rocker arms and shafts are the 2nd of 3 vital components that transfer motion from the camshaft to the valves, controlling the opening and closing of the engine valves. Over time, these parts are subjected to wear and damage, resulting in excessive play and noise in the valvetrain.
The increased valve lash causes lifter ticking, which, if not promptly addressed, can result in more damage and potential engine failure.
10. Carbon buildup
Carbon buildup can occur in the engine over time, particularly if the mill is not properly maintained. But even if it were, carbon can still accumulate on the valves, lifters, and other components, leading to oil flow and delivery issues and (again) eventual lifter ticking. The valves are likewise not as seamlessly operable as before — as often observed by vehicle owners the moment the carbon buildup has set in.
Lifter Tick Symptoms
Because the valvetrain is an integral part of the power mill (permitting air and fuel to enter the combustion chamber and exhaust gases to exit), it is almost natural for a lifter tick to synchronously occur with engine-related symptoms. It could set off the oil pressure light due to a drop in oil pressure, result in excessive exhaust smoke, or cause misfiring.
You may also notice the ticking sound growing louder during startup, in cold ambient temperatures, at higher speeds, or when idling. Conversely, the tapping goes away once the engine warms up.
Because its symptoms resemble other engine noises, some vehicle owners mistake the lifter tick sound for rod knocking. But while both can be heard from a vehicle’s engine bay, the noises have distinct characteristics — on top of having different sources.
Lifter Tick vs. Rod Knock
In my previous article on the causes and fixes of the rod knock, I pointed out that it is characteristically a metallic sound. The same is true for lifter tick — except that, situationally, they are inverse. For instance, a lifter tick tends to grow increasingly louder when idling. But under the same circumstances, a rod knock sound would either decrease or completely disappear.
A rod knock is a loud “knocking” noise heard from the engine when connecting rod bearings become worn or damaged. This wear or damage is often attributed to excessive play between the rod and the crankshaft. Because of where the connecting rod latches to and what it supports, rod knocking is noticeably louder when the engine is under load. It is also considered to have more serious repercussions.
Meanwhile, a lifter tick is a somewhat softer version of the abovementioned engine noise and affects the valve lifters instead of the rod. It is typically caused by physical damage to the lifters or oil-related anomalies (detailed descriptions of these causes in the earlier section).
Differentiating between these engine noises by ear is not an exact science, but certain pitches point to specific components. Deeper knocking noises are typically from below the location of the crankshaft or indicative of worn connecting rod bearings (but are not limited to these parts). Heavy deep noises, on the other hand, usually signify a blown timing belt tensioner.
How to Fix a Ticking Lifter
If your engine develops a lifter tick rather quickly, the first thing to do is shut off the power mill and check the oil level. Find the engine oil dipstick and see if you need to add oil or if levels are up to spec. Then go from there and follow the below steps, depending on what you suspect.
If Due to Accumulation of Dirt and Debris
- Locate the source of the noise.
- Identify the type of lifter you have.
- Confirm that all components are complete.
- Degrease or clean the valve lifter.
- Check and adjust the valves and valve lash.
- Apply lubricant on the lifter to prevent further wear and tear.
- Replace the lifter if prior steps are to no avail.
Caused by Dirty or Contaminated Oil
- Verify that the lifter tick is not caused by a worn-out or damaged part.
- Change the engine oil and flush out all the old oil before adding a fresh one.
- Make sure that the new oil used is the exact type and is OEM-specified (preferably synthetic oil or a synthetic blend unless advised otherwise).
- Use a high-quality additive to keep the oil at its best.
- Run the engine for around 30 minutes to an hour to allow the oil to circulate and work its way through the system.
- Verify if the ticking noise disappears after performing these steps.
If Suspecting a Parts Issue
- Inspect pushrods to ensure they are straight.
- Check that the rocker arm and rocker arm shaft are correctly attached.
- Verify that the valve lifters are undamaged.
- Adjust the valve lash, tightening or loosening as needed.
- Note that although hydraulic valve lifters are self-adjusting, adjusting the valve lash may solve the issue.
- Consider the assistance of a professional mechanic if unsure about performing these steps.
Conclusion — Lifter Ticking: Causes & Fixes
Even with proper upkeep, high-mileage vehicles with older engines are prime candidates for the onset (if not accelerated stages) of valve lifter wear.
With these in mind, it is certainly in everyone’s best interests to stringently perform oil-related maintenance and check on engine system components regularly. Doing so reduces the possibility of hearing a lifter tick noise.
But if it cannot be helped and you need to get to safety, know that 80 to 100 miles at moderately slow speeds is the extent of your driving with a bad lifter.
Kris is an avid off-roader and outdoor enthusiast who loves to brave the elements and take on challenging terrain. He also enjoys sharing his passion and knowledge with others so that they, too, can appreciate the ride.