Valve Lifter Buyer's Guide
The valve lifter is a small component that sits on top of the valve to increase its height and close the clearance between the valve and the camshaft.
In some engines, you can locate the valve bottom of the pushrod.
Overhead valve engine designs use pushrods to open and close the valves, while overhead cams directly operate the valves with the camshaft.
The types of valve lifters are mechanical, hydraulic, and roller.
Valve lash varies depending on the specification of the engine and should be checked regularly using a feeler gauge.
Bad valve lifter symptoms include clicking noises caused by the hammering of parts.
OE valve lifter replacements on CarParts.com are priced anywhere between $0.33 and $300 depending on the type and assembly.
There are at least 40 moving components inside the engine. All of these works connectively to provide the ideal amount of power to move your car. Among the well-known moving engine parts are the pistons, camshaft, crankshaft, and valves. There are smaller components that are used to keep the operation in its optimum state. One of these is the valve lifter, a tiny part you can locate over the valves of your engine.
For starters, valve lifters are small and designs vary according to type. If you’re looking forward to buying a valve lifter replacement, here are the important facts you need to know.
What is a valve lifter?
The valve lifter, also known as a valve tappet or lash adjuster, is a small piece of equipment that sits on top of the valve to increase its height and close the clearance between the valve and the camshaft. In some engines, you can locate the valve bottom of the pushrod. To understand more about valve lifters, let’s take a closer look at the top part of an engine.
There are two types of internal combustion engines based on the design and layout of the valve and camshaft: overhead valve (OHV) and overhead cam (OHC). Overhead valve engine designs use pushrods to open and close the valves, while overhead cams directly operate the valves with the camshaft. The operation requires precision as the cam (or the rocker pad in OHVs) and valve intermittently come in contact with each other.
Now, depending on certain factors such as wear or metal expansion due to heat, the distance from the cam or rocker pad to the tip of the valve stem can increase or decrease. This gap is known as the valve lash. Too great of a valve lash and the valve can create a pinging noise that can damage the valve over time. On the other hand, too little clearance can get the valve stuck open and cease the cylinder’s operation.
To adjust the valve lash, car manufacturers started fitting valve lifters on their models as standard equipment.
Types of valve lifters
OHVs and OHCs both use valve lifters to adjust or eliminate a lash. Since the designs hugely differ cam position, the type of valve may vary from one engine to the other. There are three types of valve lifters: mechanical, hydraulic, and roller.
Also called solid lifter, the mechanical valve lifter is a fixed piece of metal so it can’t adjust on its own. Mechanical lifters require maintenance as the lash can potentially increase as time goes by. Valve lifter noises are commonly observed on engines using mechanical lifters that are not well-maintained.
This is the most common type of valve lifter in the industry today mainly because they require little to no maintenance. It also reduces the clearance and noise that mechanical lifters can develop over time. With the hydraulic valve lifter, the engine may enjoy no gaps between the components. Hydraulic lifters feature an oil-filled assembly that automatically adjusts itself depending on temperature changes and part wear.
A roller lifter can either be mechanical or hydraulic but with a roller at the tip of the assembly. The roller helps in reducing the friction between the valvetrain components. Roller lifters offer the best care for the valves as these components produce the highest friction points in an engine.
What causes the valve lifter to fail?
The main enemy of valve lifters is the failure to observe regular maintenance, especially with solid or mechanical lifters. Valve lash varies depending on the specification of the engine and should be checked regularly using a feeler gauge. Adjust the gap between the rocker pad and the valve stem if the measurement is off from the standard specs.
Failure to maintain the ideal valve lash can damage not only the lifter but the cams and the valve as well. A failing lifter can cause the parts to bump at an extreme rate of speed as long as the engine is in operation. It can also potentially damage the engine as it can disrupt ignition in the affected cylinder.
Symptoms of a bad valve lifter
Bad valve lifter symptoms include clicking noises caused by the hammering of parts. However, apart from audible symptoms, a damaged lifter can also bend and break the pushrod as it is the weakest link of all the valvetrain components. This would eventually lead to an inoperative cylinder, which could cause a domino effect in your engine’s performance.
Some extreme repercussions of a faulty valve lifter are broken rocker arms, damaged cylinder heads, or, worse, complete engine damage. These are more expensive to repair so replace a faulty valve lifter as early as possible.
How much is an OE valve lifter replacement?
There are enough engine valve lifter manufacturers to keep the price competitive in the aftermarket scene. OE valve lifter replacements on CarParts.com are priced anywhere between $0.33 and $300 depending on the type and assembly. The cheapest is the mechanical type, while the most expensive is the 4-valve lifter in a set of four from Replacement. Before you purchase a lifter, make sure to check which type your engine is using.
To avoid buying the wrong part, consult a certified mechanic or input the basic information of your vehicle in the filter tab, such as its year, make, and model.
Finding the Right Valve Lifter for Your Ride
Does your engine sound noisier than usual? Has it decreased power along the way? If your engine hasn't been on its best behavior for the past weeks, then it's about time you get a new valve lifter. It doesn't take a mechanical genius to choose the right set. Here's a rundown of the things you need to know when choosing the right one.
Hydraulic lifter vs. Solid or mechanical lifter
Valve lifters come in two types: the hydraulic and the solid or mechanical lifter. The predetermined clearance setting of a solid or mechanical lifter allows the valves to operate more effectively and efficiently, giving your engine more power. This feature lets you set the lifter clearance to RPM and eventually supply your engine with the much needed power. However, this type of valve lifter tends to get noisy. It is also more difficult to use due to its need for continuous adjustment.
If you prefer something that's easier to maintain, a hydraulic lifter would be a better choice. It is the most common type of valve lifter and is also cheapest. Since this kind of lifter uses oil pressure to apply load to your push rod, it doesn't need constant adjusting in order to perform well. However, the disadvantage of using this type is that it produces less power than a mechanical lifter. So if you don't mind the loss of power and you want to go for something less complicated, a hydraulic valve lifter is your best bet.
Roller attachment vs. Flat tappet
There are basically two ways in which you can install your valve lifter: through roller attachments or flat tappets. Whether it's a hydraulic or mechanical type, flat tappets allow your lifters to ride on the camshaft's lobe. This style of attachment is usually inexpensive. But it can also produce friction and horsepower-robbing drag. So if you want something that's longer lasting and more powerful, then you should install a hydraulic or mechanical lifter (whichever you prefer) with a roller-style attachment. This protects the lifter from premature wear by using a steel wheel that strides above your camshaft. This design keeps the part from making direct contact to your camshaft's lobes and, as a result, reduces friction. Although it is more expensive than a roller-type lifter, the extended lifespan makes it worth the cost.
OE replacement vs. Direct fit
As a rule of thumb, always go for OE replacement parts to ensure the quality of your valve lifter. This is the closest you can get to an OE-quality lifter, and the extra cost would ensure that you get what you pay for. Although direct-fit parts are cheaper, they are also more susceptible to damage. Aside from their substandard quality, some direct-fit parts do not offer a warranty. So just to be on the safe-and more cost-efficient-side, always purchase OE replacements.
Adding New Valve Lifters for a More Powerful Engine
Located inside your engine block, valve lifters allow the right amount of air to enter your cylinder. In other words, they start the entire process of running your engine. So when you hear clicking and clacking sounds throughout your drive, this is your engine screaming for help replace your lifters. Although replacing this part requires some mechanical experience, this guide can help you with this tedious process.
Difficulty level: Moderate
Tools you'll need:
- Socket wrench and socket set
- Socket extensions
- Needle-nose pliers
- Valve lifter replacement
- Open the hood of your car. In order to properly see your valve lifter, you must remove both your intake manifold and valve covers. Unscrew and pry off both parts to expose the heads of the valves.
- Aside from your air intake and valves, you will also find that your push-rod is blocking the view to your lifter. To remove it, simply pull it out together with your rocker arms.
- To gain access to your valve lifter, you should also disassemble your cylinder head and the tappets below. Using a socket wrench, unbolt and lift the head off the engine. Next simply release and remove the exposed tappets to expose your lifters.
- Using needle-nose pliers, grip the head of each lifter and remove them from its recess. Do this process for all remaining valve lifters until all your old ones are pulled out.
- Install your new lifters by lowering them into the recesses.
- Once you've placed all your lifters, reassemble your tappets. Make sure you put just the right amount of tightness when securing your tappets. Using any kind of professional measuring equipment, adjust your tappets accordingly.
- Follow steps 1 to 3 in reverse order to put back all the parts you removed. Tighten all the bolts to secure every part in place.
- Before test-driving your new lifters, make sure you allow your engine to run for about five minutes. This will let you know if your tappets are well adjusted. If your engine gives out a tapping noise, you have to tighten them. If it runs a little rough, then make sure to loosen your tappets. When everything feels right and your engine running smoothly, take your car out for a spin.