Notes on changing the thermostat:
Parts ordered: new thermostat, coolant temperature sensor and washer, and coolant drain bolt washer.
You will also need 1.83 L (1.93 US qt) of coolant to fill the radiator and 0.26 L (0.27 US qt) to fill the coolant reservoir.
The FSM procedure for
Removing the Thermostat is on page 6-4.
To drain the coolant it refers you to Changing the Coolant – FSM page 3-28
To remove the throttle bodies it refers you to Removing the throttle bodies – FSM page 7-5
The FSM says to remove the coolant reservoir to drain it. I did not remove it. I sucked the coolant out using a cooking baster and put a piece of vinyl tubing on the tip so it would reach the bottom of the reservoir. This worked OK but was a bit messy, the coolant dribbled out of the baster.
A large syringe would work better. A 300 ml syringe would hold all the coolant, 0.26 L (260 ml), but I think I will order a
150 ml syringe to use next time. A smaller one takes up less space for storage and using it 2 times would get all the coolant out.
The FSM says to remove the throttle bodies. I did not completely remove it. I removed all the electrical connectors and loosened the clamp screws. I did not remove the 2 throttle cables or the throttle body joints. I lifted it off and used some heavy cord to hang it off to the side from the fill neck on the radiator.
The FSM says to remove the coolant temperature sensor. I see no need to remove it unless you are replacing it or testing it. I was replacing it and it came out easy with a 19 mm deep socket.
The FSM says to remove the radiator inlet hose that is attached to the thermostat cover. I did not remove the hose, just removed the cover from the engine and pulled out the old thermostat.
Installing the Thermostat – FSM page 6-5
The FSM just says “Install: Thermostat” and gives a TIP to install the thermostat with the breather hole
facing forward.
There is also a bolt hole for the cover at his position, so the breather hole would line up right behind that bolt hole.
Or worded more like Don described it in his reply above, the hole should be oriented so that it is in the
highest position, which makes more since, it is a breather hole. Either way, both descriptions would be correct.
The thermostat breather hole is easy to see, it’s a 3 mm (about 1/8”) diameter hole.
The spring end of the thermostat goes in to the engine side as Don mentioned above and as shown in the diagram in the FSM. The cover is such a tight fit that I don't think you could install it backwards anyway.