Join Date: Jan 2007
Car: 2004 Facelift CDTI Con SE - Jaguar XF Prem Lux
[QUOTE=T-Cut;4081744]I realise this is a one step at a time process, but why the 90C target? These engines will produce best performance at 95-100C, like the petrols. If you do establish a 90C system, I'd take it further to where the optimal point lies, but so far so good.
I have just changed the thermostat in my R75, I had thought for some time that it was stuck open and it was, once cleaned out it closed but as I had a new stat anyway I used the new one, incidentally both stats are marked 88 deg C.
I am sure you chaps already know this; the purpose of a thermostat in any engine is to maintain the optimum temperature to ensure optimum efficiency. Heat is generated when the engine works ie load, my engine would cool down in winter when load was reduced; it cooled down because too much coolant was going to the radiator.
Once an engine is up to temperature and the stat is operating normally, jacket water temperature will be maintained plus or minus a few degrees at what the stat is set at.
Regards what temperature the R75 diesel should run at, if BMW fit 88 deg C stats then I would hesitate to run them any hotter.