Hello Board,
A little question?
I recently replaced my w/p on m103 87 300e, the tstat housing cover and the tstat. My ? is on the tstat housing there is a bleeder screw. Should it be tight or loose. The car ran hot over 80. The old tstat /temp never ran hottier than 80. The temp setting on the new tstat is 195/90. Any advice.
Thanks

if the tstat is rated at 90 then you should have no worries about it because until it's at 90C it's not fully opened you are going to see higher temps or else the tstat will not be functional.

Thanks for the reply. Car ran under 60 at idle. Once I drove a few minutes thats when the car ran over 80. Are you saying that that will be a normal thing?

yeah you probably didn't have a working thermostat before, and the coolant ran throughout the cooling system regardless of engine temperature.

did you have any slight issues of the car not being able to provide enough heat to the cockpit? Not something you'd notice if you don't live somewhere that hits 0C all the time.

with a working thermostat it should be around 80 running, 90-ish when standstill idling after running or stop and go in traffic, and beyond 90 if you were at 90odd when you switch off the car and turn it back on after the heat soaks in.

that's pretty normal.

Also not too sure about your model by my generation W202 C class has self-bleeding mechanism built-in into the coolant reservoir, and you shouldn't have any worries about bleeding screw on the tstat housing that way....but I don't know your model well enough to tell if you do have a self-bleeding system or if that bleeder screw is really what you think it is.

Thanks for the info. The high temp was a surprise.