ok so this has been going on now a few months with my bmw m62 engine, so going back about 8 weeks ago i fitted a 80degree thermostat kit, emptied the system as much as possible filled with new coolant etc.
i noticed while moving at around 60/70mph temps would rise to around 98degrees, after climbing a hill around 102 to 104, and if sitting in traffic has peaked as high as 110 on a couple of occasions. temps did however come down but not very quickly.
so i asked the question a few weeks back and i had 2 trains of thought towards the problem one was water pump or viscous fan, the other was the addition of a large air cooled transmission cooler strapped to the front of my rad.
anyway on the weekend i fitted a new hella viscous unit, the old one was very oil soaked on the front and i never heard the 'roar' of it working so can only guess it was faulty, the new one works fine cuts in around 93/94 degrees and definately fully locks up with a roar. i also fitted at 140 (1.4 bar) expansion bottle cap.
my problem is however i'm still getting high temps wheils running although not as high as before, i'm still getting 96/97 degrees running at around 60mph this doses drop as low as 93/94 at 40/50mph and a peak of 102degrees sat in traffic although this did come down 3 or 4 degrees as soon as i started to move.
other have said with the 80deg thermostat they never go over 90deg so i may still have an issue, could the trans cooler be causing higher temps as it's strapped to the rad reducing cooling or possibly the water pump not circulating coolant as it should (i currently have a britpart water pump fitted) my other thought is it could be a faulty temp sensor as i've noticed the temp rises quicker when it reaches 99 degrees than it does below, but dash temp gauge stays central. the engine definately dosent feel as warm as it did when i was running the 105 degree stat.
i noticed while moving at around 60/70mph temps would rise to around 98degrees, after climbing a hill around 102 to 104, and if sitting in traffic has peaked as high as 110 on a couple of occasions. temps did however come down but not very quickly.
so i asked the question a few weeks back and i had 2 trains of thought towards the problem one was water pump or viscous fan, the other was the addition of a large air cooled transmission cooler strapped to the front of my rad.
anyway on the weekend i fitted a new hella viscous unit, the old one was very oil soaked on the front and i never heard the 'roar' of it working so can only guess it was faulty, the new one works fine cuts in around 93/94 degrees and definately fully locks up with a roar. i also fitted at 140 (1.4 bar) expansion bottle cap.
my problem is however i'm still getting high temps wheils running although not as high as before, i'm still getting 96/97 degrees running at around 60mph this doses drop as low as 93/94 at 40/50mph and a peak of 102degrees sat in traffic although this did come down 3 or 4 degrees as soon as i started to move.
other have said with the 80deg thermostat they never go over 90deg so i may still have an issue, could the trans cooler be causing higher temps as it's strapped to the rad reducing cooling or possibly the water pump not circulating coolant as it should (i currently have a britpart water pump fitted) my other thought is it could be a faulty temp sensor as i've noticed the temp rises quicker when it reaches 99 degrees than it does below, but dash temp gauge stays central. the engine definately dosent feel as warm as it did when i was running the 105 degree stat.