We remove the cylinder head to replace the gasket under the cylinder head, as well as for repair.

Disconnect the negative terminal of the battery

Drain the coolant

Remove the ancillary drive belt (article - Replacing the Cummins ISF3.8 ancillary drive belt)

Removing the turbocharger

Снятие и установка ГБЦ двигателя Cummins ISF3.8

We remove the exhaust manifold (for a complete disassembly of the cylinder head, when replacing the gasket, you can not remove it)

Remove the thermostat housing and take out the thermostat

Remove the coolant bypass tube

Removing the high pressure fuel pipes

Unscrew and remove the ramp

Remove the intake manifold

Снятие и установка ГБЦ двигателя Cummins ISF3.8Снятие и установка ГБЦ двигателя Cummins ISF3.8

To do this, loosen the clamps of the charge air intercooler air ducts, remove the air duct.

Unscrew the mounting bolts, remove the air elbow, the upper gasket, the air inlet heater of the starting aid and the lower gasket.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

We remove the pressure sensor in the intake manifold with the temperature sensor assembly:

- disconnect the intake manifold pressure sensor connector;

- unscrew the screw;

- remove the sensor straight up, taking care not to damage the O-ring.

We unscrew all the bolts securing the intake manifold to the cylinder head and remove the intake manifold.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

Removing the gasket

We tape the channels in the cylinder head with tape so that debris does not get into.

We remove the fuel outlet pipes.

Disconnect the cooling pipes of the air compressor

Remove the cylinder head cover:

- disconnect the engine wiring:

- loosen the screws securing the cylinder head cover (the screws cannot be removed and are part of the cover).

Снятие и установка ГБЦ двигателя Cummins ISF3.8Снятие и установка ГБЦ двигателя Cummins ISF3.8

Carefully lift and remove the cover

We remove the valve levers (rocker arms) for this:

- we loosen the lock nut;

- unscrew the adjusting nut;

- Unscrew the rocker arm mounting bolts;

- remove the rocker arms and valve bridges. Bridges and rocker arms must be installed in their places, so we mark them and lay them out on the table in the right order.

Снятие и установка ГБЦ двигателя Cummins ISF3.8Снятие и установка ГБЦ двигателя Cummins ISF3.8

We remove the rods of the pushers.

We put marks on the rods of their location. The booms must fit into place.

We remove the nozzles.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

After that, evenly in several passes, unscrew the bolts and remove the cylinder head.

Disassembly, inspection, cleaning and repair of the cylinder head will be discussed in a separate article.

Installing the cylinder head

Install a new cylinder head gasket.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

Depending on the protrusion of the piston after grinding the cylinder head or cylinder block, a cylinder head gasket can be fitted in one of three sizes.

If the piston protrusion exceeds 0.5 mm, the cylinder block must be replaced.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

Cylinder head gasket thickness:

- nominal spacer 1.25 mm

- repair No. 1 -1.50 mm

- repair - No. 2 - 1.75 mm

Install the cylinder head.

a) Carefully lower the cylinder head onto the cylinder block dowel pins.

Note: The cylinder head weighs over 23 kg.

b) Lubricate the threads and under the bolt heads with engine oil.

c) Install the bolts and hand tighten.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

d) Tighten the cylinder head bolts in the sequence shown in the figure.

Torque:

- first stage 70Nm

- Stage 2 loosen by 180 °

- 3 stage 60 nm

4 stage 60 Nm,

- turn 90˚

- turn 90 °

Install the injectors.

Install the push rods.

Note: The booms must be installed where they were removed from.

a) Install the rods into the pusher recess.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

b) Lubricate the end of the boom with engine oil

Install the rocker arm assembly.

Note: all rocker arm parts must be installed where they were removed from.

a) Tighten the adjusting screws completely, then tighten the lock nut.

Снятие и установка ГБЦ двигателя Cummins ISF3.8Снятие и установка ГБЦ двигателя Cummins ISF3.8

b) Lubricate the rocker shafts with engine oil

c) Install the axles in the rocker arms.

d) Install the rocker arms on the support.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

Note: Do not confuse intake and exhaust rocker arms.

e) Install the valve bridges in the places from where they were removed.

f) Install the rocker arms with support assemblies in the places from which they were removed.

Снятие и установка ГБЦ двигателя Cummins ISF3.8

g) Tighten the mounting bolts of the supports.

Tightening torque 36 Nm

 Снятие и установка ГБЦ двигателя Cummins ISF3.8

Install the intake manifold.

a) Install the intake manifold and tighten the bolts. Apply thread locker (# 3824041) to bolts prior to installation.

If the intake manifold was installed through a gasket, replace the gasket with a new one. If the intake manifold has been seated with RTV sealant, remove the old sealant and apply a new one (# 3164070).

Tightening torque 24 Nm

Install the cylinder head cover.

a) Install the cylinder head cover.

b) Tighten the screws.

Tightening torque 9 Nm

Install the fuel rail.

Install the fuel return pipes.

Install the high pressure fuel pipes.

Install the coolant bypass pipe.

Install the thermostat housing.

Install the exhaust manifold.

a) Apply a high temperature anti-stick compound to the exhaust manifold mounting bolts.

b) Install the exhaust manifold, new gaskets, spacers and lock plates.

c) Tighten the exhaust manifold mounting bolts in the sequence shown in the figure.

Tightening torque 53 Nm

Снятие и установка ГБЦ двигателя Cummins ISF3.8

Install the turbocharger.

Install the ancillary drive belt.

Connect the air compressor cooling pipes to the cylinder head.

Connect the wires to the battery.

Fill with coolant.

Start the engine and check for leaks.