Thermostat Install DIY by Eimer123

By diyauto
( 2 )

3 minute read

Thermostat Install DIY

Compliments of Eimer123 @


Ok I did my 195 to 180 thermostat today along with the coolant flush, GMB Water pump, and Gatorback belt.

180 thermostat - Napa #530080 (needs modifying)
Coolant - Prestone Dex cool
GMB water pump - #120-4350
Good Year Gatorback Belt - #4060875

Ok so ever since I have been a member people have always wondered which way the thermostat goes, and what the heck is the notch that people are talking about. And how you need to modify the much cheaper Napa thermostat that does not have a notch. Here are the pics!

First things first. My pictures are taken from the top of the engine looking down.

To remove the thermostat cover required a 8mm socket (2 bolts)

Old 195 thermostat

White o-ring thingy removed

Old on left, new on the right


Why the notch is needed

Direction of the flange in the o-ring

O-ring installed on the new thermostat

Inserting new thermostat

Also 180 stat+ water has moved my temp gauge down from halfway (see picture)