I've searched and googled photos but can't seem to find exactly what I'm looking for.

The hose routing in and out of the heater core. Stock cooling system, new parts including radiator.

The natural bends in the hoses would lead me to believe that the coolant outlet from the manifold goes to the heater core connector towards the drivers side and the passenger side heater core connection goes back to the cooling matrix.
I've attached a picture from another post on this forum that showed it routing the opposite way.

I'm pretty sure the heater core is open so wondering if it matters, I'm trying to get rid of the air trapped in heater core (causing waterfall noise). Thought perhaps reversing the flow would help.

I know this has been touched on hear and there but couldn't find any definitive answer if they could be reversed and if there is a benefit for bleeding system.

Thanks all!

 

To follow up, it looks like the older Disco's have it "reversed" compared to what I'm thinking is correct in my 04 D2.
See below.

 

Have at it

 

Wow, I've had them backwards for months since my head gasket job and other general parts replacements. No wonder the bubble didn't want to move up.
Thanks much!

 

Inner metal heater line goes to outside heater core connection, outer metal line goes to inner heater core connection with OEM setup.

However your LR will not explode with them going straight in/out. The air bubbles will move thru the system especially at higher RPM (thats why on a gurgling D2 it’ll stop after the RPM’s go up as the bubbles are pushed out of the heater core & thru the rest of the cooling system).

I just unclogged my heater core 1.5 weeks ago, and had to cut off the original heater hose. I replaced it with 5/8 heater hose & went straight in. It was either that or wait a week for a replacement OEM style hose. After I bleed the air out I have no gurgles or air in the system & the heater is now fully functional.

**You might want to flush the heater core out pushing water thru it the opposite way you had it flowing thru it. You might be surprised if some goo shoots out. I had a trickle of flow and then it blew out a nice blob of what looked like calcium deposits. After that if flowed fast and clear. I then flushed it the other way just in case. Once I was happy with the flow I put it all back together.***

 

Yeah the picture you show is the older D2 setup. Hose from engine crosses under the other and attaches to passenger side (NAS) and flows into the heater core. The driver side flows out and heads directly to merge into the hose between the thermostat and the water pump.

 

I was thinking of re-routing my heater hoses this way to just to reverse flow the heater coil since it's cold. I'd like to do this for the next couple of months and see what happens to the heater coil.

 

Took me longer to carefully cut off the old hoses than flushing the core out and installing the new 5/8 hoses took!

 

System designed to be flowing through the core 24/7 when engine is running. Direction doesn't matter since there is not a once typical heater control shut off valve. Direction in/out will not affect the circulation of coolant through the rest of system.

Expanding upon Best4x4's flushing of coolant snot...swapping the direction of flow on a regular basis may reduce the possibility of getting blockage since it should reverse flush deposits prior to building to a clog.
.....

 

I guess my theory was that if there's an air bubble at the top of the heater core and the coolant flow was in the direction of top to bottom (non-crossed lines) that it would be harder for the bubble to pass.
Coolant flowing from bottom to top of heater core (crossed) might help the air push through easier.

Just my theory.
I got a new OE hose kit for my 04 and the lengths and fit are perfect for the "crossed" bottom to top flow.
I feel much better about it and watched bubbles pass up into the nice new overflow tank after refilling the system.