Index

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L23/30H

Description

The cooling water system consists of two separate systems. The low temperature (LT) and the high temperature (HT) circuits.

Low Temperature Circuit

The low temperature circuit is used for cooling of the charge air and the lubricating oil, and the alternator if the latter is water cooled.

L23/30H

High Temperature Circuit

The high temperature circuit is used for cooling of the cylinder units.

Cooling water is led through a distributing pipe to the bottom of the cooling water space between the liner and the frame of each cylinder unit. The water is led out through bores in the top of the frame via the cooling water guide jacket to the bore.

Thermostatic Valve

The thermostatic valve in the high temperature circuit is mainly located imediately after the outlet of the engine, but alternatively in the external cooling system near the fresh water cooler.

The cooling water enters through the cover (A) under which the thermostatic elements are located.

The number of elements depends on the size of the valve.

The outlet to the suction side of the pump is marked

(B) and outlet to the cooler is marked (C).

In the warming-up period the cooling water is bypassing the cooler. When the outlet water from the cylinder heads reaches the normal temperature (7585° C) a controlled amount of water passes through the cooler.

The thermostatic elements must be replaced if the cooling water temperature during normal operation deviates essentially from the one stated in the test report.

L23/30H

The thermostatic valve cannot be set or adjusted, and requires no maintenance.

In some plants a corresponding thermostatic valve is installed in the low temperature circuit. The thermostatic elements of this valve have an other temperature range.

A

C B

Fig. 1. Thermostatic Valve

08028-0D/H5250/94.08.12

L23/30H

Description:

Check of cooling water system.

Hand tools:

Starting position:

Engine is running

Related procedure:

Checks to be carried out.

1)Examine the piping system for leaks.

2)Retighten all bolts and nuts in the piping system.

3)Move all valves and cocks in the piping system. Lubricate valve spindles with graphite or similar.

4)Check flexible connections for leaks.

5)Checkmanometersandthermometersforpossible damages.

6)Check the condition of the uppermost of the two O- rings (which makes up the tightening between the jacket cooling water space in the frame and the crankcase) by means of the inspection holes in the engine frame - see also Working Card 506-01.40.

For check of the fresh water condition, see section 504.