Lubricating System; Oil Pump - Volvo MD2010 Workshop Manual

General
The engines are provided with a pressure lubricating
system with an oil filter of the full flow type.

Oil pump

The oil pump is placed in the intermediate gear in the
transmission, and from where it is also driven.
The pump is of the rotor type with an inner and outer ro-
tor placed eccentrically in relation to each other. The in-
ner rotor has one "cog" less that the outer rotor.
The function of the pump is based on the increase and
decrease of the space between the outer and inner ro-
tor cogs. During the first part of the inner rotor's rotation
speed the volume is increased, whereby an underpres-
approx. 1/2 turn the space is reduced and a pressure
condition occurs which presses out oil through the
outlet.
Reducing valve
The oil pressure is limited by a reducing valve. The
valve is placed in the lubricating system just in front of
the oil filter and is fitted on the right-hand side of the cy-
li nder block in front of the oil filter.
The valve opens at excessive high pressure and releas-
es oil back to the sump.
Crankcase ventilation
To prevent overpressure and to separate fuel vapour,
steam and other gaseous combustion products, the en-
gine is fitted with enclosed crankcase ventilation.

Lubricating system

Oil filter
The oil filter is of the full flow type which implies that all
the oil is filtered before it is pressed out to the bearing
areas.
The filter is placed on the right-hand side of the cylinder
block. The filter element consists of folded filter paper.
I n the bottom of the filter there is an overflow valve
(A, Fig. 82) which opens and releases oil past the filter
if the insert should be blocked.
The filter is of the disposable type and is scrapped after
use.
Fig. 82. Oil filter
A. Overflow valve
5 1