You want your engine to run smooth, strong, and without problems. But sometimes, the pushrods are not the right length, and that can hurt your motor. You may hear ticking sounds, or even feel a drop in power. You don’t need to guess anymore. In this article, you’ll learn how to measure for pushrod length in a simple, clear, and easy way. You’ll find the exact steps to follow, and you don’t need to be a pro to do it right.
Get the Right Tools Ready
To measure pushrod length, you must have a few simple tools before you begin. Getting ready is the first big part of doing this job right. Without the correct tools, you might waste time, get the wrong size, or even damage your engine. Many people rush into this job and regret not preparing well first.
The first tool you need is a pushrod length checker. This is a small adjustable tool that looks like a pushrod but can change length. It lets you test different lengths before you buy the final pushrods. Most auto parts stores or online shops sell these. Make sure to get the one that fits your engine type, like small block Chevy or LS.
You also need a rocker arm, the correct lifters (either solid or hydraulic depending on what you run), and the cylinder head bolted in place. You will also need a dial caliper. This is a tool that lets you measure the checker pushrod when you find the right size. If you don’t have a dial caliper, you can take your pushrod to a machine shop and ask them to measure it.
You will also need a black marker, a small wrench or socket set to rotate the engine, and some white grease or dry-erase marker to check the rocker tip’s contact pattern. A light source helps too.
Now, many beginners skip using checking springs and try this with the full valve springs. That’s hard to do. You can swap in soft checking springs to make your job much easier.
Get everything laid out on a clean table. Make sure you know which cylinder you’ll be checking. Most people check cylinder 1 since it’s easy to reach.
So your checklist of tools is:
- Pushrod length checker
- Dial caliper
- Rocker arms
- Lifters (same type as you’ll run)
- Cylinder head torqued in place
- Dry erase marker or white grease
- Socket wrench to turn engine
- Light source
- Checking springs (optional but helpful)
- Clean space to work
With everything in place, you are ready to begin. This first part may not seem exciting, but without it, you could make costly mistakes. It’s all about doing it right from the start.
- Pushrod checker helps test different lengths
- Dial caliper measures exact size
- Use soft springs if you can
- Always use same lifters you’ll run
- Clean setup saves time later
Set Up the Cylinder Head and Valvetrain
Before you can measure anything, you need to set up the head and valvetrain like it will be when the engine runs. This is where many people get confused, but it’s not hard once you break it down.
Start by installing the cylinder head you’re going to use. Bolt it down using the right torque. You don’t need the full engine together—just the one cylinder you’re testing. Usually, that’s the #1 cylinder.
Next, install the lifter into the lifter bore. Make sure to use the same lifter you plan to run in the engine. If you’re using a hydraulic lifter, make sure it’s not pumped up with oil or full of air. Many builders use a solid lifter for measuring even if they plan to run hydraulic lifters, just to make things easier. That’s fine, but remember the difference when ordering pushrods. The pushrod length may need a small change if you switch types.
Then, put the camshaft in a position where the valve is closed. That means the lifter is sitting on the base circle of the cam. The base circle is the round part, not the lobe. This is where the lifter is at its lowest point, and that’s when you measure.
To do this, you can put a socket on the crank bolt and turn the engine by hand. Watch the rocker arm or pushrod so you know when the valve opens and closes. When the valve is closed, and the rocker is sitting still, you are ready to measure.
Add your adjustable pushrod checker and install the rocker arm. Don’t fully tighten it yet—just snug it up. Now turn the pushrod checker until all slack is gone and the pushrod has zero lash. Zero lash means there’s no gap, but also no pressure. It should just barely touch at both ends.
If you use a hydraulic lifter, you may also want to add preload, usually about half a turn more after zero lash. But for measuring, many builders just find zero lash.
This setup must be right because if the head isn’t bolted down or if the lifter is wrong, your pushrod measurement will be wrong too.
- Bolt cylinder head with right torque
- Use lifter type you plan to run
- Turn engine so cam is at base circle
- Adjust pushrod to zero lash
- Rocker arm should be snug but not too tight
Mark the Valve Tip and Check the Pattern
This step tells you if the pushrod length is correct by looking at how the rocker tip touches the valve stem. This is a key test, and it’s easy to do with a few simple tricks.
Take a dry erase marker or white grease and mark the top of the valve stem. Just a thin line is enough. You want to see how the rocker arm rolls over it when the engine turns.
Next, with your rocker arm installed and pushrod at zero lash, turn the engine over by hand. Use a socket wrench and turn slowly. Watch the rocker arm as it pushes the valve open and then closes again.
After the full motion, stop and look at the mark you made. You’ll see a pattern—a small line that shows where the rocker tip touched the valve. This pattern tells you a lot.
If the mark is too far to one side, the pushrod is too short or too long. You want the pattern to be as narrow and centered as possible. A good pattern is small, right in the center of the valve tip. If the pattern is wide or near the edge, that means the pushrod length is wrong.
Now go back and adjust your pushrod checker. Make it longer or shorter and repeat the process until the contact pattern is centered.
This takes time. Some builders do it five or six times before getting it right. Don’t rush. Getting the pattern perfect helps your engine live longer, makes it quieter, and gives you more power.
- Mark valve tip with marker or grease
- Turn engine by hand to see rocker motion
- Check the mark left by the rocker tip
- Look for a narrow, centered line
- Adjust pushrod length if needed and test again
Measure the Pushrod Length with Caliper
Once you’ve found the length that gives the best rocker pattern, now it’s time to measure that pushrod checker. This is how you find out the final length to order.
Take the pushrod checker out carefully without changing its length. Set it aside on a clean table.
Now grab your dial caliper. This tool lets you measure in thousandths of an inch. Gently place the ends of the caliper on the ends of the pushrod checker. Make sure you go from tip to tip.
Read the measurement. It might say something like 7.650 inches or 8.000 inches. Write this number down. That’s your measured pushrod length.
But wait—you’re not done yet. You need to check if the pushrod you buy needs to match the exact checker or if it should be shorter or longer. That depends on the tips. Some pushrod checkers use flat tips, but real pushrods have ball tips that add a little length.
So, if you used flat tips, subtract about 0.050 inch to get the final pushrod length. But if your checker had ball ends like real pushrods, then order the size you measured.
Also, think about lifter preload if you use hydraulic lifters. Some builders add or subtract a few thousandths to get the right preload. For example, if your pushrod checker shows 7.800 and you want 0.030 preload, you can order 7.770-inch pushrods.
If you’re not sure, call a pushrod company. They can help you choose based on what you measured.
- Remove checker pushrod carefully
- Use dial caliper to measure tip-to-tip
- Write down exact measurement
- Adjust for tip shape if needed
- Check preload needs for hydraulic lifters
Double Check with Full Setup Before Ordering
Before you spend money on new pushrods, it’s a smart move to check everything one last time. This is where you double-check your work to avoid costly mistakes.
Start by going back through the steps. Put your adjustable checker back in the engine. Reinstall the rocker arm and lifter. Rotate the engine one more time and check the contact pattern again. Make sure it’s still centered.
Also, check how the pushrod feels. At zero lash, there should be no gap, but no pressure. Turn the pushrod with your fingers. It should have slight drag but not be tight.
Look at the pattern again after turning the engine through its full cycle. If it still looks good, you can trust your measured length.
Check your notes. Compare the final measured length with what the pushrod maker recommends for your engine type. Some engine types have known pushrod ranges. If you’re way outside that range, double-check everything again.
You can also install all parts—lifters, rockers, and head—and try the test on a second cylinder to be sure. It may take more time, but peace of mind is worth it.
Many builders also use checking springs here to make sure valve motion is correct. Real springs can be hard to compress by hand.
After this final test, if everything looks good, you’re ready to order your pushrods.
- Recheck pattern with final setup
- Feel for smooth zero lash
- Compare with known pushrod ranges
- Test second cylinder if unsure
- Use checking springs if needed
Order and Install the Right Pushrods
Now comes the final part—getting the right pushrods and putting them in your engine. This step feels great because you’ve done the hard work.
Take your final measured length and use that to order your pushrods. Choose high-quality ones from a trusted brand. You can pick chrome-moly, hardened, or other types based on your engine use. Street engines need different pushrods than race engines.
Order the correct number for your engine—usually 16. Make sure they match your lifter type and rocker setup.
When the pushrods arrive, inspect them. Lay them flat on a table. Roll each one to see if it’s straight. They should roll smooth without wobble.
Now install them. Put the lifters in, set the pushrods into place, and install the rocker arms. Make sure each pushrod seats correctly into the lifter and rocker cup.
Turn the engine by hand again and check that nothing binds. Check the valve motion.
If you use hydraulic lifters, add the right preload. Usually, that means turning the rocker nut half a turn more after zero lash.
Tighten everything to spec. Now your engine is set up with the correct pushrod length. You’ll hear less noise, see smoother idle, and feel stronger power.
- Order pushrods based on final length
- Check for quality and straightness
- Install with care
- Add preload if needed
- Check motion by turning engine
Quick Guide
| Task | What You Need to Do |
|---|---|
| Get Tools Ready | Use pushrod checker, caliper, lifters, rocker arms |
| Set Up Head and Valvetrain | Install head, lifters, rockers, turn engine |
| Check Rocker Contact | Mark valve tip, check pattern, adjust checker |
| Measure Final Length | Use caliper, adjust for tip type and preload |
| Double Check All Work | Test again, recheck pattern and feel |
| Order and Install Pushrods | Buy based on length, install, add preload |
Final Thoughts
Taking time to measure your pushrod length the right way can save your engine from future problems. You don’t need fancy tools or a pro shop—just patience and care. Each step builds on the last, and once you do it right, you’ll feel more confident with your engine. Getting this part right gives you peace of mind. Your engine will thank you with smooth running, quiet operation, and better performance.
Frequently Asked Questions (FAQs)
Is it hard to measure pushrod length at home?
Measuring pushrod length at home is not very hard if you have the right tools and take your time. Many people worry it’s a job only engine builders can do, but that’s not true. You just need a pushrod length checker, dial caliper, and a few simple tools. The hardest part is turning the engine slowly and watching the rocker motion. But once you do it step by step, it gets easier. This is a great way to learn more about how your engine works and avoid costly mistakes in the future.
Can I reuse old pushrods if the length looks close?
You can reuse old pushrods only if they are the exact correct length and not damaged. Sometimes people try to save money by reusing parts, but it’s not always safe. Pushrods wear out over time, especially at the tips. If they are too short or too long, they can cause valve noise, poor performance, or even damage. It’s better to measure and be sure. If your old pushrods match your needed length and look good, then maybe yes. But always double-check with a caliper and look for wear marks or bent shapes.
Do I need different pushrods for solid and hydraulic lifters?
Yes, solid and hydraulic lifters often need different pushrod lengths. That’s because hydraulic lifters compress a little bit, while solid lifters do not. When you measure with solid lifters but plan to use hydraulic, you need to subtract some length to allow for preload. Also, hydraulic lifters may have different cup heights. That changes the overall pushrod length needed. Always match your measurement method with the lifters you’ll be running. And if you’re unsure, pushrod companies can help you figure out the exact size based on your parts.
Is it safe to guess pushrod length based on someone else’s setup?
Guessing pushrod length is never safe, even if someone else has the same engine. Small differences in camshaft, lifter brand, head milling, valve length, and rocker arms all affect pushrod length. What works for one engine may not work for another. If you guess, you could end up with a noisy valvetrain or worse, bent valves or worn parts. It only takes one small difference to throw things off. Measuring takes a little time but gives you the correct answer every time. It’s the best way to protect your engine.
Can pushrod length affect engine noise?
Yes, the wrong pushrod length can cause engine noise. If the pushrods are too short or too long, your valve lash or lifter preload will be off. That makes the rocker arms noisy or causes ticking sounds. Sometimes it sounds like the lifters are bad, but it’s just the wrong pushrod length. Once you install the right size pushrods, the engine becomes quieter and smoother. Many people are surprised how much better their engine sounds with the correct pushrods. It’s a small part that makes a big difference.
Do I need to measure pushrod length after changing rocker arms?
Yes, anytime you change rocker arms, you should recheck pushrod length. Rocker arms come in different shapes, ratios, and sizes. Some sit higher or lower on the head, which changes the geometry of the valvetrain. Even if you think it’s a small change, it can affect how the pushrod fits. Measuring again only takes a little time and gives you peace of mind. It’s better to double-check than risk running the wrong length. Every change in your top end setup can affect pushrod needs.
Can short pushrods cause engine damage?
Yes, short pushrods can cause engine damage over time. If the pushrods are too short, the rocker arms may not sit right on the valve tips. That can lead to poor valve lift, bad timing, or even parts that slap against each other. The lifters may not preload correctly, and that causes valve lash problems. Over time, this can wear out the camshaft, lifters, and valves. Even though it seems small, pushrod length is very important. Always measure and make sure everything fits perfectly before running the engine.
Do I have to remove the engine to measure pushrod length?
No, you don’t have to remove the whole engine. Most people measure pushrod length with the engine partly built. You just need the cylinder head installed and the lifters, rocker arms, and camshaft in place. Many builders do this on an engine stand or even with the engine still in the car, if there’s room. You only need to turn the crankshaft by hand to check valve motion. So, while it takes some work, you do not have to remove the engine completely. It’s a job you can do with care and time.