Thermostat Installation Note

WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

Do not apply oil (such as engine oil, ATF) to the rubber seal part of the thermostat. Otherwise, the O-ring could swell causing a seal malfunction.

Install the thermostat with the jiggle pin aligned with the notch of the water outlet.

Fig 1: Installing Thermostat With Jiggle Pin

Courtesy of MAZDA MOTORS CORP.