Adjusting hydraulic lifters on a Big Block Chevy is a crucial step in ensuring the engine runs smoothly and efficiently. Hydraulic lifters play an essential role in regulating valve movement, which impacts engine performance and longevity.
Proper adjustment ensures that the lifters operate quietly and effectively, avoiding potential damage to the engine’s internal components. Whether you’re assembling a new engine or fine-tuning an existing one, understanding the process and following the right steps can make a significant difference in achieving optimal performance.
This guide on how to adjust hydraulic lifters on a big block chevy will walk you through the process, providing clear instructions and tips to get the job done correctly.
Why Adjust Hydraulic Lifters?
Hydraulic lifters work by utilizing a small piston and hydraulic oil to maintain the correct clearance between the lifter and the camshaft. This mechanism allows for automatic valve lash compensation, ensuring that the valves open and close at precisely the right time without any manual adjustments needed.
However, over time, these lifters can become worn or lose their ability to compensate for valve lash accurately. That’s why it’s essential to periodically adjust them to ensure optimal engine performance.
It’s also worth noting that the Big Block Chevy engines are known for their high-performance capabilities, making proper adjustment of hydraulic lifters even more critical. A poorly adjusted lifter can lead to issues such as valve float, decreased power output, and excessive wear on valvetrain components.
Tools Required
Before starting the adjustment process, make sure you have all the necessary tools on hand. These include:
A Feeler Gauge:
This is used to measure the gap between the lifter and the camshaft. It comes in various sizes, so make sure you have one that matches your engine’s specifications.
Wrenches:
You will need a set of wrenches to loosen and tighten bolts on the engine.
Valve Cover Gaskets:
These gaskets are necessary for removing and replacing the valve covers without damaging them.
Torque Wrench:
This tool is essential for tightening bolts to the correct torque specifications.
8 Step-by-step Guidelines on How to Adjust Hydraulic Lifters on a Big Block Chevy
Step 1: Remove the Valve Covers
Start by ensuring the engine is cool and parked in a safe, stable location. Disconnect the battery to avoid any accidental electrical issues during the process. Next, locate the valve covers on your Big Block Chevy engine.
Using the appropriate wrench, carefully loosen and remove the bolts securing the valve covers. Once all bolts are removed, gently lift the valve covers off the engine.
Be cautious not to damage the valve cover gaskets, as you’ll either need to reuse them if they’re in good condition or replace them with the new gaskets specified in the tools section. With the valve covers removed, you’ll have clear access to the rocker arms and hydraulic lifters, allowing you to proceed to the next step.
Step 2: Align the Camshaft
To correctly adjust hydraulic lifters, you need to start with the camshaft in a specific position. Turn your engine over by hand using a wrench on the crankshaft pulley bolt until the timing marks align precisely at the top dead center (TDC).
This step is crucial because it ensures that all valves are closed and there is no pressure on any of them. This eliminates any potential damage or injury during the adjustment process.
Step 3: Determine Which Cylinder to Adjust
With the engine at the top dead center (TDC) on the compression stroke of cylinder #1, you can begin determining which hydraulic lifters to adjust. At this position, both the intake and exhaust valves for cylinder #1 will be fully closed.
Refer to the firing order of your Big Block Chevy engine (typically 1-8-4-3-6-5-7-2 for most models) to establish the sequence in which you adjust the remaining cylinders.
To confirm you are on the correct stroke for cylinder #1, check that the rotor inside the distributor is pointing toward the position of the #1 spark plug wire.
If it is not, rotate the crankshaft one full revolution (360 degrees) and recheck the alignment. Starting with cylinder #1 ensures the process begins accurately before moving on to other cylinders in the firing order.
Step 4: Adjust the Intake Valve Lash
Using a feeler gauge, measure the gap between the lifter and the camshaft for the intake valve of cylinder #1. Refer to your engine’s specifications to determine what this measurement should be (typically around .020 inches). If the gap is too large or non-existent, you’ll need to adjust it.
To make adjustments, use a wrench to loosen the bolt on top of the rocker’s arm until you can wiggle it back and forth. Then, slide in your feeler gauge between the lifter and camshaft.
Tighten the adjusting nut with your wrench until there is slight resistance when pulling out the feeler gauge. Then, turn the nut an additional 1/4 to 1/2 of a turn, depending on your engine’s specifications.
Step 5: Adjust the Exhaust Valve Lash
With the intake valve for cylinder #1 adjusted, the next step is to adjust the exhaust valve lash. Using the feeler gauge, measure the gap between the lifter and the camshaft for the exhaust valve of cylinder #1. Similar to the intake valve adjustment, refer to your engine’s specifications to determine the correct gap, which is typically around .020 inches.
Loosen the adjusting nut on the rocker arm for the exhaust valve using your wrench. Insert the feeler gauge between the lifter and the camshaft. Slowly tighten the adjusting nut until you feel slight resistance when pulling the feeler gauge out. After achieving the initial adjustment, turn the nut an additional 1/4 to 1/2 of a turn as specified in your engine manual.
Once you’ve completed this step for the exhaust valve, double-check both adjustments for accuracy before proceeding to the next cylinder in the firing order. Properly adjusted exhaust valve lash ensures optimal valve timing and prevents excessive wear or damage to the valvetrain components.
Step 6: Repeat the Process for Remaining Cylinders
After adjusting the intake and exhaust valves on cylinder #1, move to the next cylinder in the firing order and follow the same steps until you’ve completed all cylinders. Remember to use caution when removing and replacing valve covers to avoid damaging them or the gaskets.
You may also want to consider replacing the valve cover gaskets with new ones at this time, especially if they show signs of wear or damage. Once completed, turn the engine over by hand again to check that all valves are operating correctly and there is no excessive resistance.
Step 7: Reinstall Valve Covers
Once all adjustments have been made, carefully place the valve covers back onto the engine, making sure not to pinch or damage any wires or hoses in the process. Use a torque wrench to tighten down each bolt according to your engine’s specifications. Avoid over-tightening as this can cause damage.
You may also want to consider painting the valve covers or adding any desired decals before reinstallation. This step is optional but can add a personal touch to your engine’s appearance.
Step 8: Reconnect the Battery and Start the Engine
With everything back in place, reconnect the battery and start your Big Block Chevy engine. Check for any signs of excessive noise or unusual performance that may indicate an issue with the adjustments. If all sounds good, you’ve successfully adjusted the hydraulic lifters on your Big Block Chevy!
Remember to regularly check and maintain proper valve lash adjustment to keep your engine running smoothly and efficiently. You can refer to this process whenever necessary, whether adjusting after initial installation or as part of routine maintenance.
With a little time and effort, you can ensure your hydraulic lifters are properly adjusted to keep your engine running at its best. Happy driving!
Frequently Asked Questions
Q1: Why is It Important to Adjust Hydraulic Lifters on a Big Block Chevy Engine?
A1: Properly adjusting the valve lash helps maintain optimal valve timing and prevent damage to the valvetrain components, ensuring your engine runs smoothly and efficiently. Additionally, it can help prevent potential safety hazards such as valve float or engine failure.
Q2: How Often Should I Adjust the Hydraulic Lifters on My Big Block Chevy Engine?
A2: It is recommended to check and adjust valve lash every 10,000 miles or as part of routine maintenance. However, you may need to adjust them more frequently if you notice any unusual noises or performance issues with your engine.
Q3: Can I Adjust the Valve Lash Without Special Tools?
A3: While using specialized tools can make the process easier and more accurate, it is possible to adjust valve lash without them.
A feeler gauge and torque wrench are necessary for proper adjustment, but you can use other tools such as a wrench or screwdriver, in place of specific hydraulic lifter adjusting tools.
With these steps on how to adjust hydraulic lifters on a big block chevy engine, you can ensure your engine is running at its best. Regular maintenance and attention to detail can make a big difference in the performance and longevity of your engine. Happy driving!
Conclusion
Adjusting the hydraulic lifters on a Big Block Chevy engine may seem like a daunting task, but with the right tools, precautions, and attention to detail, it can be completed successfully.
This process is essential for maintaining the engine’s performance, longevity, and efficiency. By regularly checking and adjusting the valve lash, you can avoid potential issues such as poor valve timing, excessive wear, or even engine failure.
Taking the time to perform this maintenance also gives you a better understanding of your engine’s inner workings, empowering you to take control of its upkeep. With the steps outlined in this guide on how to adjust hydraulic lifters on a big block chevy, you’ll be well-equipped to ensure your Big Block Chevy runs smoothly for years to come. Happy motoring!