You can find hydraulic valve lifters in the engines of passenger cars, light aircraft, etc. Hydraulic lifters are commonly used in an internal combustion engine to maintain zero valve clearance. They are also known as hydraulic tappet or hydraulic lash adjuster. The hydraulic valve lifters appear to be a tiny cylinder that is attached to a push rod. It uses oil pressure to adjust a plunger and clear the valve train. Longer engine life and quieter operation are the important advantages of hydraulic lifters. Unlike the conventional solid valve lifters, The hydraulic valve lifters eliminate the need for periodic mechanical adjustments. These hydraulic valve lifters have the responsibility to protect the valve from the normal thermal expansion process of the engine.
Also, Read: How Do Hydraulic Lifts Work
For an accurate lifter performance, it is necessary to have adequate oil supply free from contaminants, dynamic response of the cam and valve gear, and establishment of proper dry lash specifications. What will happen when the internal mechanical components of the hydraulic valve lifter wear out? Obviously, this can cause an oil bypass or bleed-down, that disables the lifting function and create a collapsed lifter condition. This section will help you to identify collapsed hydraulic lifter symptoms and methods to check hydraulic lifters.
What are the stuck lifter symptoms?
Collapsed lifter sound will be something different from the normal noises from the engine. Instead of knocking or pinging sound, the sound produced will resemble tapping. Normally, the tapping sound will occur when the system is hot or cool. It will be an indication of sticking check valve, dirt, wear or others. The type of noise and its duration are important for troubleshooting lifter issues.
How to fix a collapsed lifter?
Before identifying how to fix these issues, you need to understand the reasons for this failure. Inappropriate lifter selection or failure will result in expensive damage to the engine that can be overcome only by changing this filter. Replacing or repairing these lifters won’t be a great deal for professionals. But, when you try to perform this action without any prior knowledge then it can affect your entire engine performance.
Contaminated oil, rough usage of the accelerator, leakage, etc.. are other important reason for stuck hydraulic valve lifter. Rough usage of the accelerator will make the piston rod bend and this can cause serious engine issues. Replacing the push rod is the only solution for this. Failures related to contaminated oil can be eliminated by changing the fluid.
Also, Read: Types of Hydraulic Valves
The following are the steps to replace a hydraulic valve lifter.
- A hydraulic valve lifter is located inside the engine. So, to replace a hydraulic lifter it is necessary to disassemble the engine. Unbolt and disconnect things like air ducts, electrical wires, and other parts. Now, remove the valve cover using the right sized socket.
- After removing the valve cover, locate the cylinder and ensure that its valves are closed. Then, move it to a convenient space that provides direct access to the hydraulic lifter.
- Remove hydraulic lifter and replace it with the new one. Assemble each removed parts after cleaning them.