Cars have what is called a hydraulic lifter which uses the pressure of the oil to adjust its plunger in order to take up all the clearance in the valve train.
By doing this, less engine noise is produced and makes it reliable for longer as it does not have to put up with as much wear and tear.
Having a hydraulic lifter that is faulty will end up in the rocker arm in most cases as well as the push rod and valve tip suffering if nothing is done about it.
Because of this, it is essential to know how to check your hydraulic lifters (see also “What Color Is Hydraulic Fluid?“).
Signs Of A Faulty Hydraulic Lifter
One of the most noticeable symptoms of your hydraulic lifter being faulty is the noise that it will emit from the engine.
It will have a distinct sound, so you don’t have to worry about getting it confused with something else going wrong with your car.
The sound will sound like something is tapping from the engine and will have quite a quick rhythm and can happen whether the engine is hot or cold.
It depends on what is causing the hydraulic lifter to be faulty such as having issues with dirt, wear, or a check valve that is sticking.
If you suspect that your car has a problem with its hydraulic lifter, you should take it into a garage to get it checked over or replace it as soon as you can.
Most of the time, replacing the hydraulic lifter is the only solution with every filter being replaced but on rare occasions, you will be able to get away with just replacing one of the filters which depend on the model and make of your car.
Keep in mind though that when one filter fails, the rest will usually follow so it is best to replace all the filters anyway.
If your vehicle is relatively old, it might be best to use hydraulic lifters that have been refurbished rather than new ones.
By getting refurbished hydraulic lifters instead of new ones, you will save money, and they will still do a good job for older cars that have fewer years left in them.
How To Check Hydraulic Lifters
There are two types of lifters, hydraulic and adjustable. Both of them work in the same way of having contact with the camshaft which provides the opening and closing of the intake valves and exhaust.
Hydraulic lifters use oil to keep the same pressurized height which then determines the opening length of the valves.
On the other hand, the adjustable valve can be changed to alter the height of the valve opening.
Both the hydraulic and adjustable valve need the correct oil pressure for it to be lubricated enough to work properly.
By going through the following simple steps, you will be able to check the lifter yourself.
The first thing you will need to do is put your car into neutral if you have a manual transmission, then apply the handbrake.
Once the engine is warmed up and at a normal temperature, check the lights on the dashboard for any that signify ‘oil’ or ‘check engine’.
If you have an oil pressure gauge, you can use it to read the pounds per square inch or psi, refer to your original user’s manual if you still have it to see what reading you should be getting.
Having an oil pressure that is too low might mean that your upper valve train has a clogged passage exit.
In addition to this, if you see a warning light that you have low oil pressure, then you should take it as a strong indication that it is the cause of the faulty lifters.
As we mentioned before, you will likely hear some weird noises coming from the engine that will sound like clacking and clicking. You should be able to hear them coming from the area near the valve covers in particular.
You will be able to hear much better if you have a stethoscope, you can put it over the plenum or valve covers and then move it from the front of the engine and then to the back but stop and listen for every six inches that you move.
A collapsed hydraulic lifter with too much air in it will make this sound as well as a lifter that is maladjusted or worn.
If you have found the source of the lifter noise, turn off the engine and raise the hood of the car. After you have done this, pull the oil dipstick out of the tube and use a rag to wipe it clean, and check the oil level before putting it back in again.
If the oil level is lying below the minimum level line or cannot be seen at all, the lack of lubrication is most likely what is causing the lifter to be faulty.
Also check to see if the oil is discolored at all, if it is white, foamy, tan, or gray, then it means that is has been contaminated, and the oil doesn’t have the lubrication and viscosity capabilities anymore.
The next step is to disconnect the negative battery cable but follow your user manual for the proper instructions on how to remove the valve covers from the car’s engine.
You must use a socket and wrench to get the valve cover bolts off of the covers.
A four-to-six cylinder engine will need you to use screwdrivers, sockets, and fuel line wrenches to get rid of certain components.
These include the vacuum hoses, fuel line, throttle linkage, and sensor wires as well as any other parts that are getting in the way of removing the valve covers.
Once you have completed this step, use the same socket and wrench to connect the negative battery cable.
Then, start the engine without revving it, instead, let it idle and check that all push rods, tappets, and valve springs are moving up and down.
If your lifters are solid, have a look at your user manual again to see the valve lash gap which should be shown in thousands of an inch.
Use the lash setting for the exhaust and intake separately and choose a feeler gauge for the correct setting for the valve at the front of the engine.
In the space between the rocker arm tappet and valve step top, stick the feeler gauge in and then pull it out.
If you feel a bit of a drag when you pull the gauge out, then all is well but if the tappet is noisy, the lock nut should be loosened on the top of the tappet using the end of a wrench.
To summarize, there are a few reasons why your hydraulic lifter is acting up, and luckily it will let you know clearly with distinctive sounds.
On most occasions, you will need to take your car into a garage so that they can replace all the filters, even if it is just one of them that is broken.
But all is not lost because if you use refurbished filters, you will save money and your old car will make it through another couple of years.
Knowing what is wrong with your hydraulic lifters will help you know what to be prepared for when you take it to get fixed.
By simply following the steps in this guide, you will understand your car much better with just a few observations and checks.