[TRM539]

Just replaced the thermostat on my 2007 660 grizzly. now it has a small leak from the bottom of the cover. I have cleaned all the surfaces that touch, but it still leaks. Does it require sealant around the edges?

 

[dezz]

No sealant is required. Take it off again and see what happened. There is something not correct.
Could be a pinched rubber seal or cracked gasket.