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Removing and Installing Cylinder Head:


To Identify Your Head Gasket Requirement, Click Here

The cylinder head can be removed without removing the engine from the vehicle,
and without removing the camshaft. On diesel engines, new cylinder head bolts
should be used every time the cylinder head is installed.

If a failed head gasket or warped head is suspected, a compression test
may aid diagnosis and should be performed before the cylinder head is
removed. A failed head gasket may be caused by a warped cylinder head.
When replacing a failed head gasket, always check the cylinder head for
straightness.

To Remove Cylinder Head:

1.Disconnect the battery negative (-) terminal from the battery.
Disconnect the ground strap from the cylinder head or intake manifold.

2. On diesel engines, remove the air cleaner and the intake air duct.
On turbo diesel engines, remove the turbocharger.

3. Drain the coolant.

4. Remove the camshaft drive belt.
5. Disconnect the accelerator cable and the fuel injection pipes.
Disconnect the wire from the glow plug bus.

6. Disconnect the exhaust pipe from the exhaust manifold.

7. Loosen the alternator mounting bolts and remove the upper alternator
mounting bracket.

8. Disconnect the coolant hoses from the outlet on the front of the
cylinder head and from the heater outlet on the left (driver's side)
end of the cylinder head. Disconnect the wires from the temperature and
oil pressure sending units, and label them.

9. Remove the cylinder head cover.

10. Gradually and evenly loosen the cylinder head bolts, beginning with
the outer bolts and working toward the center, and remove the cylinder
head. If the head is stuck, use a soft-faced mallet or pry gently with
a wooden stick to loosen it.

To Install Cylinder Head:

1. Clean the cylinder head and the gasket surface of the cylinder block.
Clean the threads of the head bolts and bolt holes with thread chasers,
and remove all foreign matter from the holes. Avoid letting debris into
the cylinders or oil passages in the cylinder block.

CAUTION


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Do not use a metal scraper or wire brush to clean the aluminum cylinder
head. These may damage the cylinder head. Instead, use a solvent to
soften carbon deposits and old sealing materials. If necessary, use a
wooden or plastic scraper.

2. Check the gasket surfaces of the cylinder head and the cylinder block
for warpage.

3. On diesel engines, reinstall the combustion pre-chamber inserts, if
they were removed while cleaning the cylinder head.

4. Place a new cylinder head gasket on the surface of the cylinder block.
The word "OBEN", found imprinted on the gasket near the part number,
should face up.

CAUTION

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Cylinder head gaskets will give a reliable seal only once. Always use
a new gasket that has not previously been compressed by tightening the
cylinder head bolts.

CAUTION

-------

Three different cylinder head gaskets are available for use on diesel
engines, identified by a number of notches or holes in the gasket near
the part number. When reassembling the same cylinder head and cylinder
block, make sure that the new gasket matches the one it replaces. When
assembling a new cylinder head, a new cylinder block, or an overhauled
cylinder block, the correct gasket must be selected by measuring piston
protrusion.

5. On diesel engines, position the crankshaft to the TDC marking. Then
turn the crankshaft opposite engine rotation until all pistons are at
nearly equal height.

6. Place the cylinder head in position on the cylinder block. Loosely
install all the head bolts, with the special washers, then thread them
in until they are finger-tight.

NOTE

----

To Insure Proper Alignment, Using Head Studs (we will soon have a
2 pack of these for sale) Is Recommended. Click Here To View The Tip.

12 MM Head

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7. Torque the bolts to 40 Nm (30 ft. lb.), in the sequence shown in.
Repeat the sequence, torquing the bolts to 60 Nm (44 ft. lb.). Repeat
the sequence a third time, tightening each bolt an additional 1/2 turn.
Alternatively, this last step may be done as two 1/4 turns.

Cylinder head bolt tightening sequence for diesel engines.

10----4----2----6----8

7-----5----1----3----9

8. Installation of the head is the reverse of the above!

9. Refill The Cooing System.

10.Run the motor till it reaches operating temperature. Retorque the head
by pulling all bolts, in sequence, 1/4 turn.


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