Index

Page 1 (1)

General

The camshaft which controls the actuation of inlet valves, exhaust valves and fuel injection pumps is driven by a gear wheel on the crankshaft through an intermediate wheel, and rotated by a speed which is half of that of the crankshaft, see fig. 1.

The camshaft is located in a high level housing in the engine frame.

The camshaft runs in replaceable, identical, steelbacked bronze bushings fitted into borings of the transverse girders in the housing.

The camshaft is built-up of sections, one for each cylinder unit. Each section is equipped with fixed cams for operation of fuel injection pump, air inlet valve and exhaust valve. The sections are assembled by bolting of the ample dimensioned and precision made flange connections, which also act as bearing journals.

Except for the foremost and the aftmost ones, the sections are identical and therefore interchangeable. The foremost section is equipped with a clutch for driving the fuel oil feed pump (if mounted). The gear wheel for driving the camshaft as well as a gear wheel connection of governor are screwed on the aftmost section.

L23/30H

The lubricating oil pipes for the gear wheels are equipped with nozzles which are adjusted to apply the oil at the points where the gear wheels are in mesh. The position of the nozzles is determined by direction of rotation of the engine.

Engine seen from aft - fly wheel end

Clockwise rotation direction

08028-0D/H5250/94.08.12

Safety precautions:

Stopped engine

Shut-off starting air

Shut-off cooling water

Shut-off fuel oil

Shut-off cooling oil

Stopped lub. oil circul.

Description:

Checking of gear wheels, bolted connections and lubricating system.

Starting position:

Related procedure:

Hand tools:

Allen key, 12 mm.

Ring and open end spanner, 19 mm. Socket spanner, 19 mm.

Replacement and wearing parts:

L23/30H

1) Dismount the covers which give access to the gear wheels, camshaft and crankcase.

Examine all gear wheels for cracks, wear and deformations. While turning the engine to enable inspection allover the circumference of the gear wheels.

2) Check all screws, nuts and bolted connections, including locking devices everywhere in the gear wheel housing, camshaft housing and crankcase to check that they have not worked loose. Tightening torques, see page 500.40.

3)Examine all lubricating oil spray pipe nozzles.

4)Start the electrical lubricating oil pump and check the oil flow everywhere. Be particularly careful to check that the oil jet hits the gear wheels correctly at the points where the wheels mesh.