I know in all honda books it says to install the thermostat with the little pin on the top most point. But what if it was installed on the bottom.
What difference would this really make.
Is it just a pressure relief or coolant flow through again some sort of pressure relief?

Just curious. Please serious answers/suggestions and no flamers.

Thanks

 

Does anyone have an answer to this. Is it crucial to have the pin on the top?????

 

What I did for my 98 accord 4-cyl 141k is I marked the thermostat jiggle pin on original thermostat near housing so I cuould place the new factory thermostat EXACTLY like where the jiggle pin sat before. I do think it does make a difference. Always use OEM Honda thermostat.

 

I understand all of that. OEM definately and the mark goes to the top.

I am just curious as to what the technical advantage of having this at the top is compared to at the bottom.

All these car junkies and no one to answer? Maybe I will post this in tech/misc.

Thanks

 

The pin is an air vent port. As the coolant is put into the system that tiny vent allows air to escape so the block and head won't have air pockets trapped in them.
'Back in my day' Mechanics used to open the T-stat a little bit and wedge an asprin tablet in the opening to act as an air vent when filling a cooling system.

 

the little nipple on the top is for air release,, it has to go to the top,, if u put it on the bottom it will be submerged in coolant thus any air canot release ,that would create an air pocket in system,,,,and u can only put the gasket one way with the arched cut to go over that nipple , so it is free to slide in and out

 

Ok.
I knew the gasket only went on one way. But good to know for some. As far as the air venting the block. That does make more sense to me. Ok thanks for better replies.
I did put this in upside down before realizing. I knew it was specific to top or bottom. I have not drove the car after installing as I am doing other things to it but wanted to make sure if it was not a big deal or what.

More work but thats cool. Thanks for responses.