Replacing the cylinder head gasket for the 2.5L duratec-v15 engine

If a leak of engine oil or coolant is detected at the junction of the block head with the cylinder block, remove the head and replace its gasket. A leak can also occur due to warping of the block head due to overheating.

You will need: all the tools needed to remove the battery, cylinder head cover, timing belt, camshafts.

1. Reduce the pressure in the supply system (see Reducing the pressure in the engine supply system).

2. Remove the battery (see Removing and installing the battery).

3. Drain the liquid from the engine cooling system (see Coolant Change).

4. Disconnect the hoses and branch pipes of the cooling system and disconnect the coolant temperature sensor.

5. Disconnect the wiring harness connector from the throttle assembly cover.

6. Remove the air inlet sleeve and air filter (refer to Removing and installing the air filter and intake silencer).

7. Disconnect the hoses from the oil cooler.

8. Disconnect the turbocharger from the cylinder head.

9. Remove the pipeline of the crankcase ventilation system.

10. Disconnect the wiring harness connector from the ignition coil.

11. Disconnect the fuel supply line.

12. Separate electric sockets of atomizers.

13. Remove the timing belt (see Duratec-v15 2.5L Timing Belt Replacement).

14. Remove the cylinder head cover (see Replacing camshafts and 2.5L duratec-v15 cylinder head cover seals).

15. Remove camshafts (see Replacing camshafts and 2.5L duratec-v15 cylinder head cover seals).

16. Remove the collector (see Removing and installing the manifold and replacing its gasket).


17. Loosen the twelve cylinder head bolts in the order shown in fig. 5.45, and then finally unscrew the head mounting bolts and remove them together with the washers.

WARNING: The cylinder head bolts must only be removed when the engine is cold.

18. Remove the cylinder head.

USEFUL ADVICE: It is more convenient to remove the cylinder head with an assistant, as it is quite heavy.

19. Clean the mating surfaces of the head and block.

20. Check up a head of the block on lack of a buckling. To do this, placing the ruler with an edge on the surface of the head, first in the middle along, and then across and diagonally, measure the gap between the surface of the head and the ruler with a feeler gauge. Replace the cylinder head if the clearance is greater than 0.1mm.

21. Establish a lining, and then and a head of the block of cylinders in an order, the return to removal, taking into account the following: – Remove from carving openings of bolts of fastening of a head of the block of cylinders oil or a cooling liquid which got there at removal of a head; – Be sure to install a new block head gasket, its reuse is not allowed; - Lubricate the bolts with engine oil; – tighten bolts on the cold engine in an order, the return shown on fig. 5.45, in three stages: 1st - with a torque of 20 Nm (2 kgf·m); 2nd - torque 60 Nm (6 kgf·m); 3rd - tighten by an angle of 130°.

22. Establish all removed details and knots in an order, the return to removal. After installing the camshafts and the timing belt, check and, if necessary, adjust the clearances in the valve drive (see Valve clearance adjustment).


23. Adjust the tension of the timing belt (see Duratec-v15 2.5L Timing Belt Replacement).

24. Fill coolant into the engine cooling system (see Coolant Change).

Pic. 5.45. The procedure for loosening the cylinder head bolts.