The pin is called a "jiggle" pin. It's there to allow the system to bleed off any air pockets that might be sitting above the level of the port on the T stat. The pin should always be pointing towards the top of the engine.
Rick
I'm a retired ASE Master/L-1 Technician. I still keep current with the latest automotive technology. Visit my blog for cool articles and TSB's: http://free-auto-repair-advice.blogspot.com
One gasket that normally comes with the new thermostat.
Follow the top hose back to the thermostat housing.
ok..i have a 2000 eclipse v6 my thermostat was located..look the bottom hose of the radiator follow that hose that goes to your engine it should be there ..kkkk..
It's inside of water outlet.
Follow the upper radiator hose to the engine to find the thermostat cover.
The thermostat is located on the head when you open the hood look at the front of the head it will be one the left side
lower radiator hose
It's just between the radiator hose and an engine.
Thermostat, or fan motor if it does not blow hard.
Probably in a housing at the engine end of the upper radiator hose
Look to the right of the visible valve cover and u will see a large coolant line leading into it. That metal part where the hose ends? Right there is your thermostat housing, and your thermostat is inside of it.
If it is the 4cly you need to remove your intake, unbolt the thermostat housing from the side of the block (it will be the one with the radiator hose going to it) pull the thermostat out. When replacing with a new thermostat MAKE SURE YOU INSTALL IT WITH THE JIGGLE PIN FACING UP!!!! I repeat JIGGLE PIN FACING UP. Burp the radiator system well and your done. Good Luck