13438 Mercury NUT, (.250-28)

Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Dispose of all fluids according to local regulations and mandates.
Note: Put identification marks on all hoses, on all hose assemblies, on wires and on all tube assemblies for installation purposes. Plug all hose assemblies and tube assemblies. This helps to prevent fluid loss and this helps to keep contaminants from entering the system.
If the alternator bracket is mounted on the cylinder head, remove the alternator. Refer to Disassembly and Assembly, " Alternator - Remove".
If the fuel priming pump and the primary fuel filter are mounted on the cylinder head, remove the fuel priming pump and the primary fuel filter. Refer to Disassembly and Assembly, "Fuel Priming Pump - Remove and Install".
Drain the coolant from the cooling system into a suitable container for storage or for disposal. Refer to Operation and Maintenance Manual, "Cooling System Coolant - Change" for the correct draining procedure.
Illustration 1 g01245537
Typical example
Disconnect the upper radiator hose from water temperature regulator housing (1).
If necessary, remove the air hose from the inlet connection.
Follow Step 6.a and Step 6.b in order to disconnect harness assembly (4) from coolant temperature sensor (2).
Slide the locking tab into the unlocked position.
Disconnect harness assembly (4) from coolant temperature sensor (2).
If necessary, follow Step 7.a and Step 7.b in order to disconnect harness assembly (4) from boost pressure sensor (3).
Slide the locking tab into the unlocked position.
Disconnect harness assembly (4) from boost pressure sensor (3).
Illustration 2 g01249835
Typical example
Follow Step 8.a and Step 8.b in order to disconnect harness assembly (4) from inlet air temperature sensor (5).
Slide the locking tab into the unlocked position.
Disconnect harness assembly (4) from inlet air temperature sensor (5).
Remove all cable straps that secure harness assembly (4) to the cylinder head. The harness assembly should be positioned in order to avoid causing an obstruction during the removal of the cylinder head.
Illustration 3 g01249474
Typical example
Remove tube assembly (6) from the cylinder head and from transfer pump (7).
Illustration 4 g01249479
Typical example
If the engine is equipped with a wastegate solenoid, remove harness assembly (9) from tube assembly (8). Remove the bolts for tube clip (10) and tube clip (11). Remove tube assembly (8) from the wastegate solenoid and from the cylinder head.
Illustration 5 g01476537
Typical example
Remove bolts (12). Note the position of any brackets that are secured by the bolts. Remove bypass tube (13) from the cylinder head. Remove O-ring seals (14) and (15) from the bypass tube.
Illustration 6 g01245538
Illustration 7 g01250785
Sequence for loosening the bolts for the cylinder head
Gradually loosen bolts (16) in the reverse numerical order to the sequence that is shown in Illustration 7. Note: Follow the correct sequence in order to help prevent distortion of the cylinder head.
Remove bolts (16) from cylinder head (17).
Attach a suitable lifting device to cylinder head (17). Support the weight of the cylinder head. The weight of the cylinder head is approximately 56 kg (124 lb).
Use the suitable lifting device to carefully lift cylinder head (17) off the cylinder block. Note: Do not use a lever to separate the cylinder head from the cylinder block. Take care not to damage the machined surfaces of the cylinder head during the removal procedure.
Place the cylinder head on a surface that will not scratch the face of the cylinder head.