I installed a new non-drilled 180*F thermostat this past weekend in order to get my engine temps up in this frigid weather. I was only able to get up to about 140-150 while driving, and it took forever to get there. I previously had a drilled 180 with 2 - 1/16" holes in it. Once I got the non-drilled installed, I noticed an immediate change, my heater actually worked again!

Fast forward to today: I was driving home from work, and I had my eyes pealed on the Aeroforce gauge. I watched the coolant temp rise degree by degree...

140, 2, 4, 6, 8....
150, 2, 4, 6, 8....
160, 2, 4, 6, 8....
170, 2, 4, 6, 8....

when it got to 180 I was expecting an immediate drop, as the thermostat would open, causing freezing cold coolant to go shooting through the engine. It didn't

180, 2, 4, 6, 8....
190, 1, 2, 3, 4...

the second it hit 195, I saw an immediate drop to 160. It then climbed slowly back up to 180, and stayed there the rest of the trip.

I don't understand what is happening. My 180 is actually opening at 195? How does the temp stay at 180?

FYI, I made sure that 180* was stamped on the thermostat before installing.

Wide swings in temperature when the thermostat opens often indicates trapped air.

is there a better way to release the air other than using the valve on the thermostat? I opened it slowly at operating temp and coolant dripped out immediately. I figured I had got all the air.

Should I open the valve right before the thermostat opens?

is that just where ur fans kicked on while u were idling? or were u moving?

I was moving at 70 mph down the highway the entire time.

ohh ok, fans had no bearing what so ever at 70.

I always run/ran a 195 in the winter for my SSEi. Mine does the same in the cold.

Autozone Duralast $7.99

I had one of those Duralast stats fail on me last winter, almost dropping a pin inside my LIM before I replaced it. Just my luck I didn't have the receipt for a new one, but no more Thermostats from AutoZone for me.

Ed