The thermostat blocks/allows coolant flow through the radiator.
Is coolant always flowing through the heater core?
Where is the water temp sensor located, the block?

89 Civic Si

 

Hmm,

Thermo.....between block and upper radiator hose. Stops water from leaving block and going to radiator until it reaches a certain temp.

I would think that coolant would never go through the heater core.

The water temp sensor is located either in front of the thermo just before the hose or......I don't know Hope this was a little help.

 

Wut!? j00 are mistaken.

That's how you get heat in the cabin! Of course it does.... but does it always flow through there? Or just when the thermostat is open?

 

brain fart.....right not touching the cooling side at all though????
The engine heats the coolant and then the coolant goes through the heater core and then back into the engine......I believe it always flows.....had a loop so it went strait back into the block.

 

Coolant only goes into the heater core when you have the heat turned on. If you look at the hoses going to the heater there is a little valve with cables attached to it. The heater lever on the console actuates those cables when you move it letting coolant into the heater core. When it's off no coolant goes it and the cool air just flows through the heater core and doesn't heat up.
The thermo switch is located on the back of the block, the water temp sensor for the temp gauge is located on the right side of the head. Might be the other way around, can't remember right now.

 

Thanks for clearing that up.

Out of curiosity, when the thermostat is closed, and the heater valve is closed, the water pump is still turning so does coolant just flow through the head/block/IM/TB? If this is the case, it seems like not 100% of the coolant flows through the radiator, even when the t-stat is open... this is surprising.