mercedesbenz Workshop Repair Guides

Mercedes Benz Workshop Service and Repair Manuals

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300CD (123.153) L5-3.0L DSL Turbo (617.952) (1982)

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Auxiliary Water Pump: Description and Operation

Recirculating (Auxiliary) Pump

PURPOSE

The recirculating coolant pump (30), which is located at the lower right side of the engine compartment, is arranged in the return circuit to provide
as needed coolant flow through the heat exchanger during heating operations even during low engine speeds.

OPERATION

The heating circuit activates the recirculating pump to provide uniform coolant flow through heat exchanger. During controlled operation, the
pump is switched on by the signal "legroom nozzles open". Electric activation is by way of unit.  

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