This article describes the removal and installation of the DL300-3/DL350-3 Wheel Loader cylinder head
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Removal
1. If the engine has EGR:
Remove water-cooled EGR cooler as instructed in the
work description for Removing the water-cooled EGR
cooler.
Remove brackets for the water-cooled EGR cooler.
2. Remove bolts for the exhaust manifold on the relevant
cylinder and slacken the bolts on the adjacent cylinders so
the relevant part of the exhaust manifold comes loose.
3. Remove cooling system bleeder hose,separate the quick release coupling at the front lifting eye.
4. Remove cable duct from the intake.
5. Remove cable ties for the cable hamess from the engine control unit.
6. Depressurize the fuel system and detach the fuel pipe running between the accumulator and fuel manifold.
7. Detach the fuel manifold and remove bolts on the relevant cylinder
8. Detach the intake manifold and remove bolts on the relevant cylinder.
9. Remove injectors as instructed in the work description for Removing the injectors.
Also remove high-pressure pipes and connection on the cylinder head at the back viewed from the coolant pump.
All parts in the fuel injection system and valve mechanism must be marked.
Everything must be reinstalled in the same position.
10. Remove upper rocker cover and then the rocker arm housing,valve bridges and pushrods.
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11. Pull the cable harness out of the lower rocker cover and remove it.
NOTE: Take care when pulling the cable harness out of
the rocker cover:the cable terminals can be damaged which can cause the nut securing the cable hamess to the injector to come loose.
12.Work on the adjacent cylinders.Remove upper rocker cover,release the cable hamess and the lower rocker cover so it can be moved.
13.Remove relevant cylinder head.Be careful with the adjacent rocker covers.
NOTE: Mark the cylinder heads if more than one is
being removed at the same time.
NOTE: If all cylinder heads are removed at the same time,the turbocharger must be removed or supported against the frame.
Installing
1. Check the liner height as described in the work description
for Checking the liner height.
2. Clean the cylinder head and cylinder block.Lubricate the
threads and below the heads of the cylinder head bolts.
3. Install a new cylinder head gasket.
4. Install the cylinder head.
5. Tighten the cylinder head as shown in the illustration and according to specification.
Cylinder head bolts can only be reused three times.Make a mark with a center punch on the head of the bolt.If any of the bolts already has three marks,it must be replaced.
6. Tighten the intake manifold.Use a new gasket.Tighten the bolts in the order 1-20 or 1-24 as illustrated.Tighten the bolts in the same order again.
7. Tighten the intake manifold and the exhaust manifold.Use new gaskets.
Install the cable bracket bolt in the lower rocker cover and
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8.Lower rocker cover.
● Pushrods.
● Valve bridge.
● Rocker arm housing.
9. Install the injector,high-pressure pipe connection and
high-pressure pipe as instructed in the work description.
10. Reset adjacent cylinders.
11.Adjust the valve clearance.
12.Install the upper rocker covers.
13. Install the cooling system vent
14. If the engine has an EGR system:
Install the brackets for the water-cooled EGR cooler.
Install the water-cooled EGR cooler as described in
the work description for Installing the water-cooled EGR
cooler.
