Difficult
Removing and replacing a head gasket in any vehicle is complex and requires an experienced automotive mechanic. There are many critical bolts and fasteners which must be removed and retightened precisely to the correct torque specs per step in order to successfully complete the job. Mistakes doing head gaskets can cause serious damage to the engine such as warping the cylinder heads or cracking the block, which would mean it needs rebuilt or replaced.
Warnings
- Follow the instructions closely.
- Use tools and supplies specifically recommended by the manufacturer
- Take pictures at each step in the process so that you can see how everything goes back together.
- Disconnect the battery before starting any work.
- Label and separate hardware that is removed so it can be put back in the same places.
- Use a quality gasket kit (Felpro, Victor Reinz, etc)
- Take great care not to drop any debris inside the engine block while it's open
- Ensure that all mating surfaces are clean and free from debris before installing a new gasket
Special Tools
- Torque Wrench
- In/Lb Torque Wrench (for cylinder head bolts)
- Jack stands / Ramps
- Oil drain pan
- Head gasket set (Felpro, Victor Reinz, etc)
- Socket and wrench set (both metric and standard)
- Screwdrivers
- Gasket scraper
- New oil, coolant and filter
- Brake cleaner
- Threadlocker
- New head bolts
- Engine hoist or lifting equipment
Time Required
4 - 12 hours depending on familiarity and experience
1. Drain and remove the coolant
* Open the radiator drain plug and allow the coolant to drain into a pan.
* Remove the top radiator hose to drain any remaining coolant.
* Remove the thermostat housing to gain access to the thermostat and seal it before disassembly.
2. Drain and remove the oil
* Open the oil drain plug and allow the oil to drain into a pan.
* Remove the oil filter.
3. Disconnect and remove the battery
* Disconnect the negative battery terminal.
* Remove the battery.
4. Remove the air filter assembly
* Disconnect any hoses or connectors attached to the air filter assembly.
* Undo any bolts or nuts holding the air filter assembly in place.
* Remove the air filter assembly.
5. Remove the upper intake manifold
* Disconnect any vacuum hoses or electrical connectors from the upper intake manifold.
* Undo any bolts or nuts holding the upper intake manifold in place.
* Remove the upper intake manifold.
6. Remove the lower intake manifold
* Disconnect any vacuum hoses or electrical connectors from the lower intake manifold.
* Label and disconnect the fuel supply and return lines near the fuel rail.
* Undo any bolts or nuts holding the lower intake manifold in place.
* Remove the lower intake manifold and inspect the gaskets for damage.
7. Remove the camshafts
* Remove the camshaft cover (it's held in place by bolts and sealed with RTV sealant).
* Turn the crankshaft until the timing marks on the camshaft sprockets are aligned.
* Use a C-clamp to compress the camshaft sprocket retainer and use the correct wrenches to hold the nut and sprockets in place while you remove the bolt (use PB blaster or similar to break it loose if needed).
* Slide the camshaft sprockets off as well as the timing belt.
* Remove the camshaft caps and lift out the camshafts, being careful not to drop the lifters.
8. Remove the exhaust header or manifold
* Disconnect any oxygen sensors or other components from the exhaust header or manifold.
* Undo any bolts or nuts holding the exhaust header or manifold in place,
* Remove the exhaust header or manifold and inspect the gaskets for damage.
9. Remove the cylinder heads
- Locate and undo any bolts or nuts holding the cylinder heads in place.
* Use the correct wrench to loosen and remove the cylinder head bolts or nuts, working in a sequence to prevent warping. It's crucial to follow the bolt sequence and torque specs recommended by the manufacturer to ensure proper sealing of the head gasket
* Remove the camshafts and lifters (if not done already).
* Gently pry the cylinder heads off of the engine block, being careful not to damage anything.
10. Clean the mating surfaces
* Use a gasket scraper or chemical solvents to clean the mating surfaces of the engine block and cylinder heads, ensuring they are free from dirt, oil and old gasket material.
11. Install the new head gasket
* Center the new head gasket on the engine block, making sure that it is properly seated in the grooves.
12. Install the cylinder heads
* Carefully lower the cylinder heads into place over the dowel pins.
* Install the cylinder head bolts or nuts and tighten them to the recommended specifications with a torque wrench in the correct sequence and increments.
13. Install the exhaust manifold
* Ensure the exhaust manifold gasket is in the correct position. Place the manifold in place and fasten the bolts or nuts securing it to the cylinder heads, tightening in a sequence.
14. Install the cams and timing belt
- Set the #1 cylinder to TDC compression stroke
- Apply assembly lube or camshaft/lifter grease to the cam/lifter contact surfaces
- Slide the cams into the channels in the heads, with the arrows on the camshaft sprockets pointing upwards.
- Install the camshaft end caps and snug them down
- Install the lifter guide rods
- Rotate the camshaft to allow installation of the lifters
- Drop in the lifters, keeping them in sequence according to intake or exhaust and cylinder
- Make sure the oil holes in the lifters will line up with the holes in the cam lobes
- Rotate the camshaft to allow installation of the lifters
- Double-check that a lifter isn't stuck when the camshaft is rotated
- Install the cam caps and torque the bolts to specifications
15. Install cam sprocket and timing belt
- With #1 cylinder still set at TDC, Install the cam sprocket and secure the retaining plate.
- Check the timing alignment marks (often white or yellow marks) on the cam sprocket and the timing chain or belt cover to ensure they align.
- If they don't align, repeat the cam installation steps.
- If the timing alignment is correct, install the timing chain/belt
16. Reinstall the intake manifolds
- Replace the intake manifold gaskets with new ones
- Install the upper and lower intake manifolds, reconnect all the hoses and electrical connections, and secure the intake bolts in place.
17. Reinstall the air filter assembly
* Reinstall the air filter assembly, being sure to attach any vacuum hoses or other components.
* Fill the cooling system with coolant, reconnect any hoses or sensors.
* Fill the oil pan with fresh oil, install a new oil filter
18. Reconnect the battery and turn on the engine.
* Ensure that all electrical components are properly reconnected.
* Turn the key to the on position, do not start the engine yet.
* The fuel pump will operate for a few seconds and the fuel gauge will move. This means the fuel system is properly pressurized.
* Turn the key to start the engine. Let it idle for several minutes as the coolant and oil circulate.
* Check for leaks and address them if necessary.
