the fact that the thermostat is designed to open at 83 and will be fully open within 8 degrees C of this is negligible..
If the thermostat just flew open fully at the optimum temperature the temperature of the coolant would drop dramatically and reduce the engine well past the optimum of 83degrees.
It is an antagonistic system, more temperature results in further opening which results in cooling via the radiator which results in closing of the thermostat and raising of the temperature and this will be tuned to a specific level, say 83degrees and hence as an average (it will always fluctuate within a small range)
I would hazard a guess that under normal operating conditions on a 20degreeC day the thermostat and cooling fans working well the water being pumped into the engine will be somewhere around 83degreesC or very close. The low heat output of this engine is demonstrated by the need for the pre-heater and the fact that it takes a while for the heater matrix to get hot. (although this isn't connected to the radiator system itself)
as standard these engines have a huge capacity to absorb and radiate heat. without the radiator being involved in the equation. I only once got worried about my engine being warm when it was stop start traffic for 5 hours on the M6 which they had closed ahead of my location and it was at 90 on the gauge, with no fans fitted.. 5 minutes worth of being off and it had dropped an apparent 10degrees.
If the thermostat just flew open fully at the optimum temperature the temperature of the coolant would drop dramatically and reduce the engine well past the optimum of 83degrees.
It is an antagonistic system, more temperature results in further opening which results in cooling via the radiator which results in closing of the thermostat and raising of the temperature and this will be tuned to a specific level, say 83degrees and hence as an average (it will always fluctuate within a small range)
I would hazard a guess that under normal operating conditions on a 20degreeC day the thermostat and cooling fans working well the water being pumped into the engine will be somewhere around 83degreesC or very close. The low heat output of this engine is demonstrated by the need for the pre-heater and the fact that it takes a while for the heater matrix to get hot. (although this isn't connected to the radiator system itself)
as standard these engines have a huge capacity to absorb and radiate heat. without the radiator being involved in the equation. I only once got worried about my engine being warm when it was stop start traffic for 5 hours on the M6 which they had closed ahead of my location and it was at 90 on the gauge, with no fans fitted.. 5 minutes worth of being off and it had dropped an apparent 10degrees.
Given the choice between Niall and the sheep. I would choose the sheep!
/Toseland
/Toseland