This will explain the procedures to properly remove and inspect the cylinder head and gasket on a 1997 Toyota Tacoma 2.7L (will relate to all other 2.7L 90’s style Toyota applications as well.)
It is important to clean away any debris from the engine to prevent anything from falling inside the engine before you begin disassembly of anything.
- 1. Disconnect battery. It is important to disconnect the battery before any major repair or service, to prevent shorts.
- 2. Remove the skid plate. Located directly under the front bottom of the vehicle will be a large plate protecting the underneath of the vehicle.You will want to remove and set aside to gain access to the lower portion of the radiator assembly.
- 3. Drain coolant. There will be a valve located on passenger side bottom of radiator. Prepare your drain pan underneath and loosen until a steady flow of coolant is draining.Removing the radiator cap will help with the flow.
- 4. Remove the intake tube. Disconnect all connections going to the air intake tube and top of filter housing. Then proceed to remove the assembly and set aside.
- 5. Disconnect upper, lower radiator hoses, and overflow tube. Remove the upper hose from the engine side, and the lower from the radiator side. Then there will be the overflow tube coming from the radiator cap.
- 6. Remove radiator fan shroud. There will be a vacuum hose mounted to the top that you remove and set aside. Then four bolts along the sides, then the shroud should be able to be slid up and out. Be careful not to damage radiator in process.
- 7. Remove the radiator. There is a bolt on each corner and it will slide up and out. Repair can be made without this step, but this will give you more room to work, and no worry of damaging the radiator.
- 8. Remove power steering belt. You will want to loosen the pulley bolt first then loosen the tensioner bolt enough you have enough slack to slide the belt off and out.
- 9. Loosen the alternator belt. Loosen the hold down bolt that is facing forwards, then start loosening the tensioner bolt until you have enough slack. (Bottom bolt might need to be loosened if stuck, or pry on toward the motor a little.)
- 10. Remove fan and pulley assembly. Using a long screw driver you can wedge it in to hold the fan from spinning (as shown in picture above) while loosening the bolts with a wrench from the other side.
- 11. Remove the power steering pump pulley assembly.
- 12. Remove the power steering pump and mounting bracket, set aside. If you remove the three exposed bolts first, the fourth will be able to be backed out with the assembly. not having to worry about removing the pulley.
- 13. Remove coil pack mount and set aside. First disconnect all the wires at the spark plugs, then remove the mounting bolts holding the coils to the passenger side of the head.
- 14. Remove the spark plugs.
- 15. Remove all hoses, cables and connectors leading to or from the intake manifold, and set aside. Make sure to feel around the entire manifold to make sure all lines are free. Including the throttle cable.
- 16. Remove EGR tube bolts at rear of intake manifold. (tube is a hard line and will not be able to twist or move much. be careful not to bend.
- 17. Remove bracket holing from underneath the intake manifold. Shown in picture.
- 18. Remove fuel supply line from top of fuel rail. WARNING: Fuel will be present as soon as you loosen it.
Photos will help show all locations of bolts and parts that will need to be removed.
- 19. Remove the intake manifold. Carefully guide it out, it will need to come away from the motor and then forward and out. Paying attention to the EGR tube connection and supply fuel line we disconnected. They will need to be guided away from catching anything on intake manifold while removing.
- 20. Remove the fuel rail assembly. The injectors should all stay with the rail while removing. Remove the two mounting bolts then slowly and lightly pull upwards to free the injectors from there seats. set aside in clean area.
- 21. Located and remove EGR tube. The other side will be going into rear of exhaust manifold, and a bracket in the rear of the cylinder head.
- 22. Remove all wire, tube, connectors on passenger side of motor. Anything connected to the head or that will get in the way of removal.
- 23. Remove exhaust manifold heat shield.
- 24. Remove exhaust hanger from transmission.
- 25. Remove exhaust manifold. It is always best to let the mounting nuts to soak with a penetrating oil before attempting to remove them. Wire brush will help with any excessive rust build up as well.
- 26. Remove the valve cover.
- 27. Remove the cam sensor. Located in the middle top driver side of head.
- 28. Align the motor cylinder #1 to TDC. You will want to align the bottom back notch on the harmonic balancer with the 0 on the timing cover. And then inspect the rear of the cam gears to make sure the dots line up. If not spin another 180 degrees and check again.
- 29. Remove the outer timing tensioner. Located on the front passenger corner of the head. 2 bolts and it will slide straight out.
- 30. Mark and Zip-Tie the timing chain and gear. This will prevent the chain from slipping or loosing time.
- 31. Hold the intake cam with wrench and remove cam bold and gear. This will normally be very tight. You will need leverage or impact gun in some cases. I then use a bungee to hold the timing up and out of the way.
- 32. Insert service bolt to hold sub gear to main gear on exhaust cam. This will eliminate the torsional spring force of the sub gear.
Recommended service bolt: thread diameter: 6mm /Thread pitch: 1.0 mm /Bolt length: 16-20 mm
IMPORTANT: Mark all cam shaft bearing caps if you plan to reinstall in the future. Make sure to keep them in order and direction as you remove them.
- 33. Remove the exhaust camshaft. Uniformly loosen all the bearing caps in this specific order , in several passes. It then should be very carefully lifted straight out of head assembly.
CAUTION: Never pry or use heavy force while attempting to remove camshaft.
- 34. Remove the intake camshaft. Uniformly loosen all the bearing caps in this specific order , in several passes. It then should be very carefully lifted straight out of head assembly.
CAUTION: Never pry or use heavy force while attempting to remove camshaft.
IMPORTANT: It Is important to keep all caps removed and camshafts in the direction and order you removed them if you plan to reassemble in the future.
- 35. Remove the front two head bolts. Holding the front portion or the head assembly to the timing cover assembly.
- 36. Uniformly and in several passes loosen all of the remaining head to block bolts in the sequence shown.
Be sure to count all the bolts once removed. There should be a total of ten bolts and ten washers.
IMPORTANT: If you plan to replace the head. is it necessary to replace the head bolts upon installation.
Prepare an area close by your able to walk the cylinder head over to and set it down nicely once removed. Clean rags work perfect.
- 37. Remove the cylinder head assembly. Carefully left up and out, the head will be heavy, you will need to guide the timing gear through the assembly and around the wire harness. I would highly suggest asking for a hand with the removal. If you drop the unit it can be damaged easily.
- Before attempting to rotate the head to inspect the bottom of the head, you must first remove all valve caps. It is easiest to use a magnet and pull them all straight up and out. I like to always keep all my pieces in order.
- In this particular case, the head gasket had blown. Causing the piston chamber to mix with the coolant system. Causing a sudden overheat, and over pressuring the coolant system.
- After flipping the head over and cleaning it up a little bit, I had noticed cracking along the edges of the valve seats. I marked all the cracks with green paint to show were the most common failures are. Any cracks in the head will result in needing to replace the head.
I hope this information helped you on your repair! Thanks for reading.