Page 165 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

Reasons for sludge formation and its prevention
Troubleshooting in lubricating system and its components

Objectives: At the end of this lesson you shall be able to
• explain reasons for sludge formation and its prevention
• demonstrate troubleshooting in lubricating system and its components.

Reasons for sludge formation and its prevention
Sludge
The piston rings prevent the burnt gases from entering the oil pump. But after some time when the rings get worn
out, these gases enter the oil pump in some quantity and in addition when we turn off the engine at night, its
temperature drops after some time. The cold air from outside enters the sump through the bead and we also know
that there is moisture in the air. When it gets even colder at night, that moisture condenses and turns into water
droplets. When water droplets mix with the engine oil and enter the sump, it turns the oil into a paste due to which
the oil loses its proper quality. This paste is called sludge.
To prevent sludge, we should do the following things -
1 Start the engine and run it fast to bring its temperature to about 60° and while working, its temperature should
be kept above 60°.
2 In cold weather, a shutter or sack should be put over the radiator.
3 Carburetor injector etc. should be checked to see if the rich mixture is not going.
4 Whether any cylinder is missing. In case of failure of the spark plug, the fuel will go inside the sump in liquid
form. Similarly, in a diesel engine, if any injector is not working properly, then instead of spraying, it will pour a
stream of oil on the piston and this oil will go into the sump through the ring.
5 The nuts of the cylinder head should be checked properly so that the water leaking through the gasket does
not go into the sump.
6 The engine should not be run at idle speed for a long time.
7 The breathing system of the engine should be kept clean.

8 Engine oil should be changed on time.
9 Oil filter should also be changed or cleaned at regular intervals.
Remember that whenever sludge is formed inside the engine, in this case not only the sump should be opened
and cleaned but also the mesh fitted in front of the oil pump and the oil galleries should be cleaned.
Troubleshooting in lubricating system and it is components

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CITS : Automotive - Mechanic Diesel - Lesson 39 - 46