cooling system circ direction

JDExSquid

Dodge 2.2TII Swap
I'm getting ready to splice the Fiat cooling system w/ the Chrysler 2.2 TII, using a Davies Craig electric pump. The Fiat cooling system seems to be VERY busy, especially at the thermostat housing. If I could figure out flow direction thru each of the components it may make my job easier. I've searched but as yet have not found flow info. Thanks!
 
This is from the shop manual. Maybe it will help?
thermostat housing flow.jpg
 
Ok, that certainly helps! A couple of questions: Does the water pump pull coolant from the thermostat housing lower side and push coolant thru the engine, returning to the thermostat housing upper side and on to the upper radiator hose? Also, with this flow direction, the rubber heater hose inside the cabin would be supply and the hard line running parallel with the coolant tubes would be return, right?
 
Does the water pump pull coolant from the thermostat housing lower side and push coolant thru the engine, returning to the thermostat housing upper side and on to the upper radiator hose?

I am not sure what you mean by "the thermostat housing lower side". "The diagram's legend says "2. Union for water pump inlet pipe." So that tells me that the water pump pulls from "2." and pushes into the block thru the large opening in the block where the pump mounts. Where "2." gets its coolant varies as the thermostat goes from closed to kinda open, to fully open.

Also, with this flow direction, the rubber heater hose inside the cabin would be supply and the hard line running parallel with the coolant tubes would be return, right?

Yep, the hard line in the center tunnel is the return from the heater circuit.
heater_hose2.JPG
 
Thanks Jim! That makes good sense. Now I have to figure out the 2.2 TII flow and combine the two. The electric water pump acts as the thermostat.
 
If you don't plumb in the electric pump in the same place as the stock pump you will need to relocate the heater return pipe to the suction side of the new pump.
 
According to pictures, it looks like the coolant is being pushed thru the left pipe into the lower left of the radiator, thru the rad, then out the upper right and returning to the engine bay thru the right side pipe. Is this to push air up toward the bleed port? The setup is opposite on the Dodge, but the rad and engine were in the front on that car.
 
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Hi Jim,

The picture shows port 4 going to the rad. Port 4 is the top port on the housing and feeds water to the right (US pass side) pipe which feeds the top port on the right of the rad. Port 3 is the lower port on the housing and receives the water back from the rad from the bottom port on the left (US driver side) of the rad. You want to be drawing from the lowest point of the rad to enhance the probability that you are drawing coolant, not air, back to the engine.
 
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