In the thread "lowering coolant temp -Success Story" Tkamiya states"The only problem with the "boil test" is that most MB cars (gas) has 87C thermostat. 87C is a start-to-open temp. It won't fully open until 102C. "
Those familiar with old threads know that many members in the heat of summer say their cars never go over 90C. There is also many members, including myself, who complain that their cars run too hot 100C-110C. Some say the higher temps are normal some say not. Some of us have spent a lot of money trying to get the temp down to no avail.
Now if Tkamiya is right about the thermostat not being fully open until 102C - is THAT temp considered normal?? If the thermostat is rated at 87C shouldn't it be fully open at that temp. On my older NA cars in the past when I bought a 165F thermostat - it was open at 165F. If Mercedes only START to open at 87C - then how in heck can people in hot climates be running at 80-90C???
I AM TOTALLY CONFUSED NOW! Any way we can nail this down once and for all??? I normally use logic to troubleshoot - but something does not make sense here - how can a car run at 80-90C in hot weather when the thermostat only BEGINS to open at 87C???