Engine lifters are critical components of an internal combustion engine. They play a crucial role in opening and closing the valves, enabling the engine to breathe and generate power. Replacing lifters can be a complex and time-consuming task, but it is essential to ensure the smooth and efficient operation of the engine. This article provides a comprehensive guide to changing lifters on a 2006 Toyota Sequoia 4.7, offering step-by-step instructions, helpful tips, and essential safety precautions to ensure a successful repair.
Before embarking on the lifter replacement process, it is imperative to gather the necessary tools and materials. These include a new set of lifters, a torque wrench, a socket set, a screwdriver, a pry bar, and a gasket scraper. It is also wise to invest in a Haynes or Chilton repair manual for the specific year and model of the vehicle. Once the tools and materials are assembled, safety should be the paramount concern. Disconnect the negative terminal of the battery, allowing the vehicle to sit for a minimum of 30 minutes before beginning any work. This will discharge any residual electrical energy, reducing the risk of electrical shock.
With the safety precautions in place, the actual lifter replacement process can commence. Begin by removing the valve covers, which are typically secured by bolts or screws. Once the valve covers are removed, the lifters will be exposed. Using a pry bar, carefully lift the lifters out of their respective bores. Inspect the lifters for any signs of wear or damage, and discard any that are visibly compromised. Lubricate the new lifters with clean engine oil and carefully insert them into the bores. Ensure that the lifters are properly seated and level before proceeding to the next step.
Locating the Lifters
The lifters in a 2006 Toyota Sequoia 4.7 are located in the engine’s cylinder head. To access the lifters, you will need to remove the valve covers and the camshafts.
Begin by removing the valve covers. The valve covers are located on the top of the engine, and they are held in place by a series of bolts. Once the valve covers are removed, you will see the camshafts.
The camshafts are located in the center of the engine, and they are responsible for opening and closing the valves. To remove the camshafts, you will need to use a camshaft removal tool.
Once the camshafts are removed, you will see the lifters. The lifters are located in the bores in the cylinder head.
To remove the lifters, you will need to use a lifter removal tool.
Here is a step-by-step guide on how to remove the lifters from a 2006 Toyota Sequoia 4.7:
1. Remove the valve covers.
2. Remove the camshafts.
3. Remove the lifters.
| Step | Description |
|---|---|
| 1 | Remove the valve covers. |
| 2 | Remove the camshafts. |
| 3 | Remove the lifters. |
Removing the Valve Covers
To remove the valve covers, you’ll need to follow these steps:
1. Gather Your Tools and Materials
Before you begin, make sure you have the following tools and materials:
- 10mm socket wrench
- New valve cover gaskets
- Torque wrench
- Clean rags
2. Locate and Remove the Valve Covers
**The 2006 Toyota Sequoia 4.7 has two valve covers, one on each side of the engine.** Locate the valve covers and remove the 10mm bolts that hold them in place.
| Valve Cover | Number of Bolts | Bolt Size | Torque |
|---|---|---|---|
| Front | 12 | 10mm | 7 ft-lbs |
| Rear | 10 | 10mm | 7 ft-lbs |
3. Clean the Valve Covers and Surfaces
Once the valve covers are removed, clean them and the mating surfaces on the cylinder head with a clean rag to remove any dirt or debris.
Removing the Rocker Arms
Once the camshafts have been removed, you can begin removing the rocker arms. Use a 12mm socket to loosen the bolts that hold the rocker arms in place. Once the bolts are loosened, carefully lift the rocker arms off of the cylinder head. Be sure to keep track of which rocker arm goes on which cylinder, as they are not interchangeable.
If the rocker arms are stuck, you can use a pry bar to gently pry them off. Be careful not to damage the cylinder head or the rocker arms. Once all of the rocker arms have been removed, you can proceed to the next step.
Installing the Lifters
To install the lifters, you will need to use a lifter installer tool. This tool is designed to help you insert the lifters into the cylinder head without damaging them. To use the lifter installer tool, insert the lifter into the tool and then place the tool over the lifter bore in the cylinder head. Use a hammer to tap the lifter into place. Once the lifter is in place, remove the lifter installer tool.
Repeat this process for all of the lifters. Once all of the lifters have been installed, you can proceed to the next step.
Installing the New Lifters
Step 5: Replace the Valve Train Components
Carefully reinstall the pushrods, ensuring that each one aligns with the corresponding lifter. Tighten the rocker arms to the specified torque (typically around 18-22 ft-lb). Install the new valve cover gaskets and torque the valve cover bolts in a crisscross pattern to the manufacturer’s specifications (usually 9-11 ft-lb).
Additional Considerations:
| Component | Torque Specification |
|---|---|
| Pushrods | 18-22 ft-lb |
| Rocker Arms | 18-22 ft-lb |
| Valve Cover Bolts | 9-11 ft-lb |
Once all the components are in place, rotate the engine crankshaft manually several times to ensure there are no obstructions or interference. Reconnect the battery and start the engine. Check for any leaks or unusual noises and let it idle for a few minutes to allow the oil pressure to stabilize and circulate through the new lifters.
Reinstalling the Rocker Arms
With the lifters installed, it’s time to put the rocker arms back in place. Here’s how:
- Lubricate the rocker arm pads with engine oil.
- Align the rocker arms with their corresponding lifters.
- Tighten the rocker arm bolts evenly using a torque wrench. The specified torque value for the 4.7L Toyota Sequoia is 22 ft-lbs (30 Nm).
To ensure the camshaft is in the correct alignment, rotate the crankshaft two full revolutions clockwise, then align the timing mark on the camshaft sprocket with the mark on the timing chain cover.
NOTE: It’s crucial to double-check the timing alignment by performing a piston stop test. To do this, install a dial indicator in the number one cylinder’s spark plug hole and rotate the crankshaft until the piston reaches top dead center (TDC). The dial indicator should read 0.050 inches (1.27 mm) of lift on the exhaust valve.
Verify that all rocker arms are properly seated and there’s no binding or excessive play.
| Cylinder | Intake Valve Clearance | Exhaust Valve Clearance |
|---|---|---|
| 1 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 2 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 3 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 4 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 5 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 6 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 7 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
| 8 | 0.010-0.018 in (0.25-0.46 mm) | 0.008-0.016 in (0.20-0.40 mm) |
Replacing the Valve Covers
Materials:
| 8mm socket | 12mm socket |
| 14mm socket | Torque wrench |
| Socket wrench | New valve covers |
| Valve cover gaskets | Spark plug wire removal tool |
| Oil |
Instructions:
- Disconnect the battery.
- Remove the engine cover.
- Remove the spark plug wires using a spark plug wire removal tool.
- Remove the bolts holding the valve covers in place.
- Lift the valve covers off the engine.
- Clean the mating surfaces of the valve covers and the cylinder heads.
- Apply a thin bead of oil-resistant sealant to the valve cover gaskets.
- Install the valve cover gaskets onto the valve covers.
- Place the valve covers onto the engine and tighten the bolts to 14 ft-lbs using a torque wrench.
- Install the spark plug wires.
- Reconnect the battery.
Tightening the Bolts
As you tighten the bolts, it’s crucial to adhere to the specified torque values to ensure proper fit and prevent damage. Follow these steps to tighten the bolts:
- Lubricate the threads and under the bolt head with engine oil or assembly lube.
- Install the bolts and tighten them snugly using a wrench.
-
Refer to the table below for the tightening sequence and torque values for the valve cover bolts:
Bolt Position Torque Center 6 bolts 54 lb-ft (73 Nm) Corner bolts 47 lb-ft (64 Nm) - Tighten the bolts to the specified torque values using a torque wrench.
- Tighten the bolts in multiple passes to ensure proper torque distribution.
- After tightening the last bolt, double-check the torque of all bolts to ensure proper installation.
By carefully following these steps, you can ensure the valve cover bolts are tightened correctly, preventing leaks and ensuring optimal engine performance.
Connecting the Electrical Components
Once the camshaft is installed, it’s time to connect the electrical components. This includes the oil pressure sensor, camshaft position sensor, and variable valve timing (VVT) solenoid. All sensors should have new O-rings before they are installed.
Oil Pressure Sensor
The oil pressure sensor is located on the side of the engine block. Remove the electrical connector and then use a 24mm socket to remove the sensor. Apply a little bit of sealant to the threads of the new sensor and then screw it into place. Torque to 22 ft-lbs.
Camshaft Position Sensor
The camshaft position sensor is located on the front of the engine. Remove the electrical connector and then use a 10mm socket to remove the two bolts that hold the sensor in place. Remove the sensor and then apply a little bit of sealant to the O-ring. Install the new sensor and torque the bolts to 7 ft-lbs.
Variable Valve Timing (VVT) Solenoid
The VVT solenoid is located on the front of the engine, next to the camshaft position sensor. Remove the electrical connector and then use a 10mm socket to remove the two bolts that hold the solenoid in place. Remove the solenoid and then apply a little bit of sealant to the O-ring. Install the new solenoid and torque the bolts to 7 ft-lbs.
**Note:** If you are replacing the VVT solenoid, you will need to reset the VVT system. This can be done using a scan tool.
Testing the Engine
1. Start the engine and let it run for a few minutes to warm it up.
2. Listen for any unusual noises coming from the engine. Lifters that are worn or damaged can make a ticking or tapping noise.
3. Look for any leaks from the engine. A leak could indicate that a lifter is leaking oil.
4. Use a stethoscope to listen to the lifters. If a lifter is worn or damaged, you will hear a clicking or tapping sound through the stethoscope.
5. Measure the oil pressure. Low oil pressure can lead to lifter wear.
6. Inspect the camshaft for any signs of wear or damage. A damaged camshaft can damage the lifters.
7. Inspect the rocker arms for any signs of wear or damage. Worn or damaged rocker arms can put undue stress on the lifters.
8. Check the pushrods for any signs of wear or damage. Worn or damaged pushrods can cause the lifters to move improperly.
9. Inspect the valve springs for any signs of wear or damage. Worn or damaged valve springs can cause the lifters to lose contact with the valves.
10. Remove the spark plugs and check the condition of the cylinders. If the cylinders are scored or damaged, the lifters may be damaged as well.
| Symptom | Possible Cause |
|---|---|
| Ticking or tapping noise | Worn or damaged lifters |
| Oil leak | Leaking lifter |
| Low oil pressure | Worn lifters |
| Damaged camshaft | Worn or damaged lifters |
| Worn or damaged rocker arms | Excessive stress on lifters |
| Worn or damaged pushrods | Improper lifter movement |
| Worn or damaged valve springs | Lost lifter contact with valves |
| Scored or damaged cylinders | Damaged lifters |
How To Change Lifters To A 2006 Toyota Sequoia 4.7
Tools you will need are an impact gun or a wrench, a 22mm socket, and a pry bar. Locate the valve cover. It is the black plastic cover that runs the length of the top of the engine. Use the impact gun or 22mm socket to remove the valve cover. Once the valve cover is removed, you will see the rockers and lifters. The lifters are the small, round pieces that sit in the middle of the rockers. Use the pry bar to remove the lifters. Once the lifters are removed, you can install the new lifters. Simply place the new lifters in the same place that the old lifters were located. Once the new lifters are in place, you can reinstall the valve cover.
People Also Ask
Q. How much does it cost to change lifters on a 2006 Toyota Sequoia?
A. The cost of changing lifters on a 2006 Toyota Sequoia will vary depending on the mechanic you choose and the parts you need. However, you can expect to pay between $500 and $1,000 for the parts and labor.
Q. How long does it take to change lifters on a 2006 Toyota Sequoia?
A. The time it takes to change lifters on a 2006 Toyota Sequoia will vary depending on the mechanic’s experience and the availability of parts. However, you can expect the job to take between 4 and 8 hours.
