How to Clean Hydraulic Lifters?

How to Clean Hydraulic Lifters? . Maintaining your engine’s health is essential for optimal performance, and hydraulic lifters play a key role in its smooth operation. Over time, these lifters can become clogged with carbon deposits, dirt, and oil sludge, resulting in engine noise, decreased efficiency, and even damage. Cleaning lifters without removing them is a practical solution for many car owners. In this guide, we’ll walk you through everything you need to know to clean hydraulic lifters without dismantling your engine.

What Are Hydraulic Lifters and How Do They Work?

Hydraulic lifters, also called tappets, are critical engine components responsible for maintaining proper valve clearance in overhead valve engines. They ensure the camshaft’s motion transfers efficiently to the valves, facilitating smooth engine operation.
Hydraulic lifters are self-adjusting, using engine oil pressure to fill the lifter and eliminate any valve lash. However, when lifters get clogged, they lose their efficiency.

Why Do Hydraulic Lifters Get Dirty?

Hydraulic lifters are susceptible to dirt and debris due to several reasons:

Carbon Buildup: Combustion byproducts accumulating in the oil system.
Old or Low-Quality Oil: Over time, oil loses its lubricating properties, forming sludge.
Neglected Maintenance: Infrequent oil changes allow contaminants to settle.

Keeping lifters clean prevents wear and tear while ensuring engine longevity.

Signs of Dirty Hydraulic Lifters

Dirty or clogged hydraulic lifters exhibit various symptoms, including:

Tapping or Clicking Noises: A noisy valve train indicates improper lubrication.
Decreased Engine Power: Inefficient lifters affect valve timing, reducing engine performance.
Increased Fuel Consumption: Improper combustion caused by valve inefficiencies leads to higher fuel usage.
Rough Idle: The engine may vibrate or run unevenly due to restricted lifter movement.

Can You Clean Lifters Without Removing Them?

Yes, cleaning hydraulic lifters without removing them is possible and effective in many cases. By using specialized products like engine flushes and oil additives, you can dissolve sludge and carbon deposits within the lifters. However, severe clogging may require manual cleaning, which involves dismantling the engine.

Lifter Cleaning Safety

Don’t let the size of a lifter fool you, it’s ready to give you problems you didn’t sign up for. You’re dealing with small, viscous springs and equally evil chemicals. Do yourself a favor and protect the soft stuff.

3M Safety Glasses
Gloveworks Industrial Black Nitrile Gloves

Everything You’ll Need To Clean Flat Tappet Lifters

To be perfectly clear, this guide focuses on the process as it relates to flat tappet lifters in a Chrysler 440. The information is still valuable to most applications with hydraulic lifters, but different applications require different steps. It’s important to research the process for your exact engine before jumping in.

As for what you’ll need to tackle flat tappet lifters, there is a right tool for the job. However, finding a vintage lifter compressor is easier said than done. Thankfully, a few basic hand tools will work fine in their place. Some picks, locking pliers, an old pushrod, lint-free shop towels, and bore brushes should all be at the ready. You’ll also need some chemicals to do the heavy lifting. My old service manual suggests using kerosene, but a cleaning solvent such as mineral spirits or lacquer thinner and your favorite degreaser will work just fine. Of course, some motor oil or assembly lube will be necessary when returning the lifters home as well.

Tool List

Neiko 38-Piece Wire Brush Set
Klean Strip Odorless Mineral Spirits
Lucas Oil Assembly Lube
Hotop 4-Piece Hook and Pick Set
Scott Shop Towels
Lumax 6-Quart Plastic Drain Pan
Irwin Vise Grip Original Locking Pliers

Organizing your tools and gear so everything is easily reachable will save precious minutes waiting for your handy-dandy child or four-legged helper to bring you the sandpaper or blowtorch. (You won’t need a blowtorch for this job. Please don’t have your kid hand you a blowtorch—Ed.)

Step-by-Step Guide: How to Clean Hydraulic Lifters

1. Access the Lifters

The first step of this process is accessing the lifters. In my case, I already had the intake removed, which provides clear access to the lifter valley of this engine. Depending on the application, that may or may not be necessary, but you want to give yourself enough room to work cleanly and efficiently in any case.

2. Remove the Lifter

I personally prefer to leave the lifters in their respective bores and work one by one. I don’t mind giving it the extra time if it means I’m absolutely sure of lifter placement. You can pull them all out at once as long as you have a system that allows you to keep track of the lifters so you can return them to the bore they come from.

Removing lifters is simple on this engine, as I can pull them out by hand. That may not be an option on some engines, and a magnet on a stick is best to pull it free.

3. Clean the Exterior

Before tearing into the lifter, give it a quick cleaning with some degreaser. Getting oil and gunk off the exterior will make it easier to work with. It also gives you the opportunity to inspect the exterior for any irregularities or wear patterns that signal bigger problems are afoot.

4. Remove the Retaining Clip

Set the lifter standing upright on your workbench. Take a spare pushrod and compress the internal plunger. It’ll be hard to get much movement out of it, but you only need just enough room for the retaining clip to easily be wiggled free.

I like to remove the outer edges of the clip first, then gently pull it free with pliers. You just need to be careful not to pull too hard and deform the retaining clip. Locking pliers are also useful in preventing the clip from springing across the room on you.

A bench vise is perfectly acceptable for holding roller lifters while removing the clip. Protective pads are always recommended, but the hard body of the lifter should be fine for light pressure. Forgo compressing the plunger for this as you will likely push the lifter out of the vise.

5. Carefully Remove the Guts of the Lifter

With the clip out of the way, the internals are free to come out. They don’t always come easy, though. You may need a little persuasion with non-marring picks. Take note of the order of everything as the internals come out.

6. Clean

Simply dip the parts in your solvent and work free any stubborn deposits with your brushes. Clean the internal portions as well as the exterior to ensure you’re leaving no debris or deposits behind. Now is the time to inspect the plunger and internal portion of the lifter for any signs of damage.

7. Assemble

Once the lifter is clean and dry, it’s time to reassemble. This is very simple, as everything goes in reverse order. Just be sure not to lose any of the small parts of the internal system, as the lifter will fail to work properly if it isn’t assembled properly.

8. Prime the Lifters?

My service manual specifically states that you are not to prime the lifters before installing them. That does not mean you don’t have to for your engine. Depending on the application and cam manufacturer, the process of priming may be necessary, which is one reason why you need to do the homework to determine what steps are necessary for the application.

9. Return Home and Repeat

Once you’re done cleaning the lifter, all that’s left is to return it to the bore you pulled it from and carry on to the next. I like to take a lint-free rag with some solvent and give the lifter bore a quick pass for good measure. Then I dab the lifter with some assembly lube, spread it around, drop it back in place, and move on.

Tips to Maintain Clean Lifters

Change your engine oil every 3,000-5,000 miles or as recommended by the manufacturer.
Use high-quality oil and filters to reduce impurities.
Regularly check for leaks that could introduce contaminants.
Avoid extended idling or short trips that prevent the oil from reaching operating temperature.

Common Mistakes to Avoid During Cleaning

Using the Wrong Additive: Ensure compatibility with your engine type.
Overlooking Oil Changes: Post-cleaning, fresh oil is crucial to prevent redepositing contaminants.
Ignoring Manufacturer Guidelines: Always follow product instructions to avoid engine damage.

Hydraulic Lifters: Repair vs. Replacement

In some cases, cleaning lifters may not be sufficient if they are heavily damaged. If cleaning fails to resolve the issue, consider these options:

Repair: Ideal for minor damage or wear.
Replacement: Necessary for lifters with severe mechanical faults.

Frequently Asked Questions (FAQs)

What happens if I ignore dirty lifters?

Neglecting dirty lifters can lead to reduced engine performance, increased wear, and costly repairs.

Are engine additives safe for all vehicles?

Most additives are safe, but always check compatibility with your engine and follow product guidelines.

How Often Should You Clean Hydraulic Lifters?

Clean your lifters whenever you notice performance issues, such as increased noise or poor fuel economy. For preventive maintenance, consider cleaning them once every 30,000 miles or during your engine’s scheduled service.

Does Cleaning Lifters Improve Engine Performance?

Yes! Clean hydraulic lifters restore proper valve timing, reducing engine noise and improving efficiency. Additionally, it enhances oil circulation, resulting in better fuel economy and smoother engine operation.