Repair Manual MAN-00
190
THAR
CRDe
BS-IV
MAY
2012
/Rev 1
The repair methods given by the manufacturer in this document are based on the technical specifications at the time of release. The methods may be modified as a result of changes introduced by the
manufacturer in the production of the various component units and accessories from which the vehicles are manufactured. The reproduction, translation, transmission, in part or whole of the present
document, are prohibited without the prior written consent of Mahindra & Mahindra Ltd. The use of this document by any person other than the trained personnel, at the Authorized Service Centre of
Mahindra & Mahindra Ltd., will amount to unauthorized use and shall be liable for penalty/prosecution© 2012 Mahindra & Mahindra Ltd.
Working principle of Crankcase Ventilation System –
The ventilation system is closed ventilation type. A hose connects the ladder frame / sump assembly
to the oil separator. Te oil separator is a labriyanth type. The oil goes through the labriyanth, the oil
collected drops down. The excess pressure acts below the diaphragm. The diaphragm is acted from
below by the crankcase pressure and from top the suction by air cleaner. A spring also acts on top of
the diaphragm. Once the pressure exceeds the diaphragm lifts and the excess crankcase pressure goes
to the air intake system.
Certain amount of oil will be carried from the oil separator to the Air inlet hose, which is normal.
However if it is excessive please look for all the causes mentioned in the high blow bye.
Oil circulation system –
An external gear type pump sucks the oil through the strainer. The oil pump is driven by the gear,
which is mounted, on the crankshaft. The oil pump delivers pressurized oil to the supply bore in the
block. This oil is delivered to the oil cooler and after getting cooled comes on the outer side of the
element. The filtered oil goes through the centre of the oil filter and is connected to the main oil
gallery.
The main oil gallery runs to the front of the block where it is delivered to the timing cover. From
therein it takes a small loop in the timing cover and again comes to the front of the block. It goes to
another oil gallery. Oil from this gallery supplies oil to the piston cooling jets
Oil from the main oil gallery goes to the crankshaft main journal and camshaft, while from the rear
end it is supplied to the alternator’s vacuum pump. The oil supply for the turbocharger is from the oil
filter bracket.
The oil routed from the main oil gallery lubricates the timing gears and the idler gear bush. Part of this
oil gets sprayed from idler shaft hole. The camshaft gear and the thrust plate are lubricated by engine
oil routed from the first camshaft bushing through the camshaft hole.
The oil from the First camshaft bush goes to the top of the cylinder and enters an oil gallery, which
extend up to 110 m from the front. Oil from this gallery comes to the base of the first rocker shaft-
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