Which direction does the coolant flow out / in the heater core on an s13?
 

I'm just curious which way the coolant flows out of the motor and to the heater core.

I'd also like to know which way coolant flows out of the motor and into the radiator.

I'm going to put an aftermarket coolant temp sensor and gauge in (for lapping days) and want to make sure I put it in the right place.

It flows out of the upper hose, through the radiator, and then back into the edge via lower hose/thermostat

For the rest of the cooling system flow, check the FSM, I don't recall off hand.

Th OEM cooalant temp sensor is in the same housing that the thermostat is in. This obviously works for OEM cars. I personally put mine on the upper hose/head outlet side, to get an idea of how warm the car actually is once it hits the radiator.

I used a CustomSteel coolant adapter (Home)

http://www.codyace.com/albums/album0...0361.sized.jpg

http://www.codyace.com/albums/album0...0001.sized.jpg

Wait a second, if you're taking the temp in the upper hose then it never fluctuates unless the car is warm right?

I want to see what the temps are like after the radiator has cooled the fluid off...

So.... put it in the lower hose.

I have it in the upper hose to see what temps the water is coming out of the engine engine, not what it's doing going in.. If it's 195* coming out, I at least know it's under that going in, and that the radiator is working by giving the engine cool water.

Thanks for that link Cody, great idea

I mean the OE sensor obviously checks the water temp on the intlet to the engine, right in the thermostat housing...so take my comment as it is. I just prefer to know what my car is doing after it's all said and done ya know?

Sounds good to me, you can also verify that the thermostat is opening when it should.

Cody, I wasn't bashing - just thinking out loud:

The temps coming out of the motor will always be the same presuming your thermostat and water pump are working correctly right? So that gauge won't show much deviation ever.

I figure I need to know the temps that are going into the motor - that will tell me if the radiator is working enough, along with the thermostat, and water pump.

I think we can all agree that the stock temp gauge is just a dummy light.