When my dad bought his new car last year, he passed his 2001 Mitsubishi Galant down to me. Just the other day, I was driving home from the store and I noticed that the engine was overheating. So, I called up a tow truck and had the old Mitsu taken to my house. I checked over the fans and the coolant level, which were both in good shape. Then I checked the thermostat, and it was stuck closed. Replacing the thermostat in my 2.4-liter-equipped Galant was similar to most other cars I've worked on in the past, with only a few minor differences.
On my Galant, the radiator drain cock was on the passenger side of the radiator. I installed the gasket around the edge of the new thermostat, and tightened its bolts to 10 foot-pounds. The cooling system on my Galant uses standard, 50-50 premixed, ethylene-glycol -- green -- coolant. I filled the radiator to the base of its neck, then started the engine and let it idle until the fans cycled on and off twice. As I let the engine idle, I topped off the coolant each time the level dropped. After the two fan cycles, I tightened the radiator cap, and waited until the engine was cool to the touch. I them filled the coolant reservoir to the "Full" line with coolant.
