Engine Coolant Circuit Flow

WARNING: This page is about a different car, the 2019 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

ITEM	DESCRIPTION
1	Heater core
2	Bleed screw
3	Cylinder head - Bank 1
4	Cylinder block
5	Throttle body
6	Oil cooler
7	Heater manifold
8	Cylinder head - Bank 2
9	Coolant expansion tank
10	Automatic Transmission Fluid (ATF) cooler
11	Thermostat
12	Check valve
13	Coolant pump
14	Radiator
15	Connection with supercharger cooling system
16	Right auxiliary radiator
17	Left auxiliary radiator

When the engine is running, the engine coolant is circulated around the engine cooling system by the coolant pump. The engine coolant flows from the coolant pump through the cylinder heads and the oil cooler into the cylinder block and the heater manifold.

In the cylinder block, the engine coolant flows forward to the engine coolant outlet. When the engine coolant is cold the thermostat is closed, engine coolant flows direct from the outlet pipe back to the coolant pump. When the engine coolant reaches operating temperature, the thermostat begins to open to control the system temperature. The engine coolant flows from the engine coolant outlet to the coolant pump through the radiator. When the thermostat is open, the coolant flows through the radiator and also generates a coolant flow through the Automatic Transmission Fluid (ATF) cooler.

From the heater manifold the coolant flows through the throttle body and the heater core, in parallel circuits that are unaffected by the position of the thermostat. From the throttle body, the coolant merges with bleed coolant from the coolant pump and the outlet pipe and flows to the coolant expansion tank. From the heater core, the coolant flows back to the inlet of the coolant pump.

The supercharger cooling system also uses the engine cooling system for charge air cooling. For additional information, refer to: SUPERCHARGER COOLING