Page 3
Lotus Service Notes
Section KJ
Thermostat Closed
Heater matrix Thermostat closed
circuit
By-pass flow
Throttle body circuit
Heat exchanger circuit
k76a
KJ.1 - GENERAL DESCRIPTION
The engine liquid cooling system comprises an engine driven water pump, flow thermostat, front mounted
radiator with two electric cooling fans, header tank, re-circulation pump, and associated plumbing.
The centrifugal water pump is mounted on the front face of the cylinder block, and is driven by the multi-
rib, serpentine auxiliary belt. The pump discharges coolant into a separate volute chamber for each of the two
cylinder banks, where, after cooling the cylinders, flow is directed upwards into each cylinder head before exit-
ing into an outlet housing bolted to the rear of the cylinder heads. From this housing, offtakes are provided for
the engine cooling radiator, heater matrix, throttle body, radiator by-pass pipe and, if fitted, an oil/water heat
exchanger. A thermostat housing is located on the timing cover above the water pump, and controls the flow
of returning coolant from the front mounted radiator.
Thermostat closed circuit (cold engine):
At coolant temperatures below 80°C (176°F) the dual valve thermostat is closed, shutting off the return
circuit from the radiator and opening a by-pass valve to admit coolant from a by-pass pipe connected to the
outlet housing on the rear of the engine. Coolant exiting the cylinder heads meets a closed radiator circuit and
is directed through four subsidiary circuits:
By-Pass:
The greater proportion of flow is via the radiator by-pass pipe back to the engine side of the thermo-
stat housing.
Heater:
An offtake on the engine outlet housing feeds the heater matrix via a re-circulation pump (see below),
pipework running through the RH sill, and a heater by-pass valve mounted to the left of the HVAC unit. Re-
turn pipework follows a parallel route and connects to the rear end of the heater return rail. This return rail is
routed down the 'V' of the cylinder block, alongside the by-pass pipe, and connects to the engine side of the
thermostat housing.
Throttle body:
A small offtake on the outlet housing supplies a flow of hot water to the throttle body to inhibit
ice formation around the valve in severe climatic conditions. An outlet hose from the throttle body connects to
heater return rail.
Oil/water heat exchanger (if fitted):
On cars so fitted, an oil/water heat exchanger is fitted on the LH side of
the cylinder block and is fed with engine lubricating oil via feed and return hoses linking to the main bearing
Summary of Contents for Evora
Page 13: ...Page 7 Lotus Service Notes Section AJ ...
Page 81: ... Lotus Service Notes Section EMR Page 9 EMR 3 COMPONENT LOCATION em239 O2 O2 O2 O2 2009 02 ...
Page 82: ...Page 10 Lotus Service Notes Section EMR em240 2009 02 ...
Page 115: ... Lotus Service Notes Section EMR Page 43 2009 02 ...
Page 116: ...Page 44 Lotus Service Notes Section EMR 2009 02 ...
Page 118: ...Page 46 Lotus Service Notes Section EMR 2009 02 ...
Page 184: ...Page 2 Lotus Service Notes Section JL GENERAL LAYOUT TBA ...
Page 207: ...Page 25 Lotus Service Notes Section JL ...
Page 233: ...Page 9 Lotus Service Notes Section MR Blank page ...
Page 259: ...Page 35 Lotus Service Notes Section MR ...
Page 260: ...Page 36 Lotus Service Notes Section MR ...
Page 261: ...Page 37 Lotus Service Notes Section MR ...
Page 262: ...Page 38 Lotus Service Notes Section MR ...
Page 263: ...Page 39 Lotus Service Notes Section MR ...
Page 264: ...Page 40 Lotus Service Notes Section MR ...
Page 265: ...Page 41 Lotus Service Notes Section MR ...
Page 266: ...Page 42 Lotus Service Notes Section MR ...
Page 267: ...Page 43 Lotus Service Notes Section MR ...
Page 268: ...Page 44 Lotus Service Notes Section MR ...
Page 269: ...Page 45 Lotus Service Notes Section MR ...
Page 270: ...Page 46 Lotus Service Notes Section MR ...
Page 271: ...Page 47 Lotus Service Notes Section MR ...
Page 272: ...Page 48 Lotus Service Notes Section MR ...
Page 273: ...Page 49 Lotus Service Notes Section MR ...
Page 274: ...Page 50 Lotus Service Notes Section MR ...
Page 275: ...Page 51 Lotus Service Notes Section MR ...
Page 276: ...Page 52 Lotus Service Notes Section MR ...
Page 277: ...Page 53 Lotus Service Notes Section MR ...
Page 278: ...Page 54 Lotus Service Notes Section MR ...
Page 279: ...Page 55 Lotus Service Notes Section MR ...
Page 280: ...Page 56 Lotus Service Notes Section MR ...
Page 281: ...Page 57 Lotus Service Notes Section MR ...
Page 282: ...Page 58 Lotus Service Notes Section MR ...
Page 283: ...Page 59 Lotus Service Notes Section MR ...
Page 284: ...Page 60 Lotus Service Notes Section MR ...
Page 285: ...Page 61 Lotus Service Notes Section MR ...
Page 286: ...Page 62 Lotus Service Notes Section MR ...
Page 287: ...Page 63 Lotus Service Notes Section MR ...
Page 288: ...Page 64 Lotus Service Notes Section MR ...
Page 289: ...Page 65 Lotus Service Notes Section MR ...
Page 290: ...Page 66 Lotus Service Notes Section MR ...
Page 291: ...Page 67 Lotus Service Notes Section MR ...
Page 292: ...Page 68 Lotus Service Notes Section MR ...
Page 293: ...Page 69 Lotus Service Notes Section MR ...
Page 294: ...Page 70 Lotus Service Notes Section MR ...
Page 295: ...Page 71 Lotus Service Notes Section MR ...
Page 296: ...Page 72 Lotus Service Notes Section MR ...
Page 297: ...Page 73 Lotus Service Notes Section MR ...
Page 298: ...Page 74 Lotus Service Notes Section MR ...
Page 299: ...Page 75 Lotus Service Notes Section MR ...
Page 300: ...Page 76 Lotus Service Notes Section MR ...
Page 301: ...Page 77 Lotus Service Notes Section MR ...
Page 302: ...Page 78 Lotus Service Notes Section MR ...
Page 303: ...Page 79 Lotus Service Notes Section MR ...
Page 304: ...Page 80 Lotus Service Notes Section MR ...
Page 305: ...Page 81 Lotus Service Notes Section MR ...
Page 306: ...Page 82 Lotus Service Notes Section MR ...
Page 307: ...Page 83 Lotus Service Notes Section MR ...
Page 336: ...Page 2 Lotus Service Notes Section QJ GENERAL LAYOUT Illustration TBA ...
Page 357: ...Page 2 Lotus Service Notes Section WF Illustration to follow ...