water pump to heater core flow direction?

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simon84
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Location: Banff, Alberta, Canada

water pump to heater core flow direction?

Post by simon84 » Sat Sep 12, 2020 10:40 pm

I'm wanting to know if the coolant flow from the water pump to the heater core goes through the metal pipe that runs under the exhaust manifold then into the heater core, back out to the heater control valve and then back into the block. This seems like the logical pathway to me but I'm not 100% sure and I know someone on here will know this.
Reason I ask is that I am installing an inline circulating water heater and it seems to have a one way flow valve. I can only blow air through it one direction. It's an old unit and I can't find much at all on the internet about installing these things.
There's also not a lot of space to fit this thing in so I may end up cutting that metal pipe so that I can tuck the heater unit under the exhaust manifold. Will want to make sure it's not too close though or it may get cooked. I have the trans and exhaust out right now so that area is fairly accessible.

Thanks for any input on this.
Driver: 87 Tercel SR5, white, 4ac, weber carb (aka the Tercedes)
Road Tripper:95 Mitsubishi Delica L400 2.8L Turbo Diesel
Motorbike: 94 Kawasaki Ninja ZX6
Project Car:Red 68 Plymouth Sport Fury III
Previous Tercel:Orange 84 Tercel 4wd (aka the pumpkin)

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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: water pump to heater core flow direction?

Post by Petros » Tue Sep 15, 2020 1:55 am

the coolant flows out of the outlet on the back of the head, goes into the heater core, and gets sucked out the long tube that runs under the manifold and goes into the back of the water pump assembly. it is easy to remember this way: the back side, center of the pump is the low pressure (suction) side of the water pump (the perimeter is the high pressie side of the impeller in the pump), and the flow in the head is on the "pressure" side of the water pump.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

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simon84
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Location: Banff, Alberta, Canada

Re: water pump to heater core flow direction?

Post by simon84 » Tue Sep 15, 2020 10:42 am

Ok, so I had it backwards. Thanks for the info and the explanation!
Kinda makes sense that the control valve is on the pipe coming from the back of the head.
This should actually make the in-line heater install a bit easier.
Driver: 87 Tercel SR5, white, 4ac, weber carb (aka the Tercedes)
Road Tripper:95 Mitsubishi Delica L400 2.8L Turbo Diesel
Motorbike: 94 Kawasaki Ninja ZX6
Project Car:Red 68 Plymouth Sport Fury III
Previous Tercel:Orange 84 Tercel 4wd (aka the pumpkin)

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