How To Diagnose A Failing Valve Lifter
You turn the key in your Ford, and you can hear is a rapid tapping noise. What could be wrong with your engine? If you've got an engine with pushrods, it's likely that one of your valve lifters has gone bad or is out of adjustment.
There are two basic types of valve lifters - mechanical and hydraulic. They can each cause a tapping sound when something is wrong, but the cause is different. A mechanical lifter can wear down, and end up out of adjustment. An adjustment can eliminate the noise. A hydraulic lifter works by using oil pressure to stay at the correct height. If it wears out, it can lose its ability to stay at the correct height. Hydraulic lifters need to be replaced when they go bad. The good news is that they are inexpensive.
If you're hearing a tapping sound, you may want to check and see if one of your valve lifters is causing the noise. We put together an easy-to-follow tutorial for you.
How Does A Valve Lifter Go Bad?
It can be hard to pinpoint how long a valve lifter should last. There are too many factors in play. Older or poorly-maintained engines have a higher risk of lifter failure, for example. Here are some of the most common causes of valve lifter failure:
- Contamination (usually dirt)
- Poor maintenance (infrequent oil changes)
- Low oil pressure
- Normal wear and tear
How To Check Your Valve Lifters
The first thing you want to do is to listen for any clicking or clacking noises coming from the top of the engine. To do this:
- Put your Ford in park while keeping the engine running.
- Grab a mechanic's stethoscope and then place it over the valve covers or the intake manifold plenum cover.
- Move the stethoscope from the front of the engine toward the back. Pause at every 6 inches to listen for any clicking or clacking noises.
- If the noise is prominent in an area, then it's likely that one of the valve lifters in that area is bad.
Determining What's Causing The Valve Lifter(s) To Fail
Once you've determined that one or more of your valve lifters has failed, you want to make sure that it doesn't happen again. This means figuring out why your valve lifter(s) failed in the first place. Here are a few things you can do:
- Check the oil pressure: Low oil pressure can cause valve lifter failure
- Check the state of the oil: Dirty oil can increase the risk of valve lifter failure
If you can't find any clear causes of valve lifter failure in your engine, it may just be normal wear and tear. This is more likely the older your engine is.
What Happens When You Don't Replace Your Valve Lifters?
Reaching far into the engine to replace your valve lifters sounds pretty intimidating. That's why a lot of Ford owners put off replacing their valve lifters. If you're in this situation, we urge you to replace your valve lifters as soon as possible.
A valve lifter may seem like a small part, but a worn out or out of adjustment lifter can cause significant damage in your engine. Related parts will wear out faster, for example. We're talking about parts inside the engine such as:
- Rocker arm
- Valve tip
- Push rod
Replacing Your Hydraulic Valve Lifters
If you have hydraulic valve lifters, and you're comfortable replacing them, we have a couple of great resources for you:
- A comprehensive step-by-step valve lifter replacement tutorial (stay tuned to our upcoming posts)
- A catalog of genuine OEM valve lifters at wholesale pricing
- This valve lifter for a bunch of 2009-2014 Ford models is our best seller
Do you have any questions about diagnosing a bad valve lifter in your Ford? You're welcome to get in touch with us!