Can I get a good answer, Thermostat question?

steplift20 · #1 01-12-2021, 03:40 PM

Let me try to make this question clear, Mercury 143 degree thermostats come with a rubber gasket, one side of the gasket pertrudes up , does that side face up on the short part of the thermostat or does it face down facing the longer part of the thermostat ?

spareparts · #2 01-13-2021, 07:26 PM

what year model? is it a square cross section gasket? which thermostat housing

steplift20 · #3 01-13-2021, 08:23 PM

It's a 1988 150 Mercury out board it has two thermostats 143 degrees they come with a rubber seal/gasket that fits into a groove one side of the seal is sticking up a little looks kind of like a hat the part that's higher on the seal does it face down towards the longer part of the thermostat or does it face up towards the shorter part of the thermostat , now I have been replacing them for along time but when I look at pics of the thermostat some times it's facing up and sometimes it's facing down I would just like to do it the right way and does it make a differance? I don't know .

spareparts · #4 01-14-2021, 12:07 AM

https://www.youtube.com/watch?v=PwpJBfse8Fs

steplift20 · #5 01-15-2021, 04:33 PM

Spareparts, thanks for the video but he is not doing it right, did you notice that? He is putting in the rubber seals then holding the thermostat up against it, the thermostat fits into a groove on the seal and he is not doing that but I think the top of the seal faces the short part of the thermostat , check out the video h he is doing it wrong. But thanks for posting it

Duke01 · #6 03-18-2021, 05:34 AM

You are correct Step, in the youtube video he is not installing the rubber seal as designed. The seal is supposed to be installed like a grommet around the flange of the thermostat (as you describe).

I believe the "hat" portion faces the shorter portion of the thermostat, but I will have to confirm that when I replace mine this Spring. The images on the internet are all over the place and are pretty useless.