Coolant Pump - Mercedes-Benz OM 651 Service Manual

Coolant pump

The coolant pump ensures that the coolant circulates
in the coolant circuit. It is made of plastic, which
makes a contribution to weight reduction.
Cross-section of coolant pump
1 Belt pulley
2 Control rod
3 Regulating valve
4 Evacuation chamber
5 Vacuum fitting
– This printout will not be recorded by the update service. Status: 09 / 2008 –
Function
The coolant pump is driven via the belt pulley by
means of a poly-V belt. The rotational movement of
the belt pulley is transferred to the shaft via the hub.
The impeller is driven by the shaft, which causes the
coolant to circulate.
The coolant flow can be stopped by vacuum via the
switchover valve of the coolant pump, which is located
on the left on the throttle valve actuator. In this case,
a regulating valve slides over the impeller, thus closing
the coolant feed.
Introduction of New Generation of 4-Cylinder Inline Engines, OM 651
6 Impeller
7 Coolant outlet
8 Power diaphragm
9 Rod seal
10 Compression spring
Coolant pump
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