Removal and installation the cylinder head (Mazda BT-50 (1))

Attention:

• Fuel vapors are very dangerous. They are highly flammable and can cause serious injury and damage. There should be no sparking objects or open flames in the fuel area.
• Fuel spills or leaks from pipes are very dangerous. Fuel can irritate the skin and eyes. Always take safety precautions when working on the fuel system (see chapter "Fuel injection system").

1. Remove the engine trim panel.



2. Disconnect the cable from the negative terminal of the battery.

3. Drain the coolant (see chapter "Maintenance and general check and adjustment procedures").

4. Remove the intake manifold and intake air duct (see chapter "Air intake and exhaust system").

5. Remove the injectors (see chapter "Fuel injection system").



6. Remove the turbocharger (see chapter "Air intake and exhaust system").

7. Remove the timing belt (see section "Timing belt").

8. Remove the parts in the order they are numbered in the figure "Removing and installing the cylinder head".

9. Installation of parts during assembly is carried out in the reverse order of removal.

10. Adjust the tension of the drive belts of the attachments (see chapter "Maintenance and general check and adjustment procedures").

11. Remove air from the fuel system (see chapter "Fuel injection system").



12. Check for fuel, engine oil and coolant leaks.

13. Start the engine and check the idle speed (see chapter "Maintenance and general check and adjustment procedures").

14. Check the end pressure of the compression stroke (see chapter "Maintenance and general check and adjustment procedures").

Note on removing camshaft bearing caps

Note: If necessary, mark the caps for subsequent installation in their places. Caution: When removing the camshaft, make sure that none of the camshaft lobes press on the rocker arms, otherwise, when removing, the camshaft may be damaged under the influence of the valve springs.

Loosen the camshaft bearing cap mounting bolts in two or three passes in the sequence shown in the figure.

Note on removing the cylinder head

1. Unscrew the bolts "A" shown in the figure.



2. Loosen the mounting bolts in two or three passes in the sequence shown in the previous figure.

Note on removing the camshaft sprocket

Caution: Do not allow the camshaft to turn, otherwise the pistons and valves may be damaged as a result of impact.

Holding the camshaft with a wrench by the hexagonal section, unscrew the camshaft pulley mounting bolt.

Note on installing the cylinder head gasket

1. Using a dial indicator, measure the piston protrusion from the cylinder block with the piston at TDC.



2. Based on the piston protrusion, select a new cylinder head gasket in accordance with the identification mark on the gasket.

Table. Selecting a cylinder head gasket.


3. Apply a layer of sealant to the cylinder block in the places marked in the figure.

Note: The parts must be installed within the time specified in the sealant application instructions. Otherwise, the sealant must be removed and reapplied.

• Layer thickness: 2.0-3.0 mm

4. Install the cylinder head.

Note on installing the cylinder head

1. Check the length of each cylinder head bolt. If the maximum value is exceeded, replace the bolt.

Note: The mounting bolts are marked with "W", "N" or "I", please check according to them.

Normal length:

• mark "W" - 101.2-101.18 mm
• mark "N" - 113.2-113.8 mm
• mark "I" - 149-150 mm

Maximum length:

• mark "W" - 102.5 mm
• mark "N" - 114.5 mm
• mark "I" - 150.5 mm

2. Apply a layer of engine oil to the threads and under the heads of the cylinder head bolts.

3. Tighten the cylinder head bolts in two or three passes in the sequence shown in the figure.

Note: Do not install the "A" bolts yet.

• Tightening torque - 29 Nm

4. Mark the heads of all mounting bolts.

5. Tighten the mounting bolts by 90-105° in the sequence shown in the figure above.

6. Tighten the mounting bolts again by 90-105° in the sequence shown in the figure above.

7. Tighten the mounting bolts again by 90-105° in the sequence shown in the figure above.



8. Apply a layer of threadlocker to the threads of the cylinder head bolts "A".

9. Tighten bolts "A" (see figure in point "3").

• Tightening torque: 18-20 Nm

Note on installing the camshaft bed

1. Apply a layer of sealant to the cylinder head as shown in the figure.

Note: The parts must be installed within the time specified in the sealant application instructions. Otherwise, the sealant must be removed and reapplied.

2. Install the camshaft bed into the cylinder head.

Note on installing camshafts

1. Apply a layer of adhesive to the mounting surface of the front camshaft bearing cover.

Note: The parts must be installed within the time specified in the sealant application instructions. Otherwise, the sealant must be removed and reapplied.

2. Install the camshafts and camshaft caps in accordance with the marks applied to them.

3. Tighten the camshaft bearing cap bolts in the sequence shown in the illustration.

• Tightening torque: 8-11 Nm

Note: Since the camshaft end clearance is very small, keep the camshafts level when installing them.

4. Apply a coat of engine oil to the lip of the new camshaft oil seal.

5. Carefully pre-install the oil seal into the cylinder head by hand.

6. Using a hammer and a mandrel of suitable diameter, press in the camshaft oil seal.

Note on installing the back cover

Tighten the rear cover mounting bolts in the sequence shown in the figure.

• Tightening torque - 8 - 11 Nm

Note on installing camshaft timing pulleys

1. Install the camshaft pulleys in accordance with the marks "I - inlet", "E - outlet" applied to them, orienting the shaft keys upward.



2. While holding the camshaft with a wrench by the hexagonal section, tighten the camshaft timing pulley mounting bolt.

• Tightening torque - 123-142 Nm

Note on installing the cylinder head cover

1. Apply silicone sealant to the contact surfaces of the cylinder head in the locations shown in the figure.

• Layer thickness: 2-3 mm

Note: The parts must be installed within the time specified in the sealant application instructions. Otherwise, the sealant must be removed and reapplied.

2. Tighten the cylinder head cover mounting bolts in two stages, in the sequence shown in the figure.

• Tightening torque: 8-11 Nm