4age heater core water flow

**Sam_Q** · 11-07-2007, 05:34 PM

I have a cooling system on my 20v that is simular to a 4age 16v and looking at it I can see no way that the water actually gets pushed through the core. Even though the water feed comes from the back of the water pump it doesnt seem to be pumped from the pump itself and the other end goes to the radiator hose.

So; where am I wrong in my assumptions, how does the water flow and in which direction.

The reason I want to know is because I want to hook up a water over oil cooler on my engine.

**Hen** · 11-07-2007, 05:38 PM

16V has the heater feed from the back of the head (so at pressure). It is returned to the remote thermostat housing (basically the same spot as the bottom radiator hose) from which the water pump sucks.

Hen

**Sam_Q** · 11-07-2007, 05:46 PM

ok sorry I need to make a correction here, a JDM rwd bigport 16V or a 4ac not an ae82 type setup like what you describe, thanks anyway

**MRMOPARMAN** · 11-07-2007, 07:12 PM

is the engine in a running car atm? if so id just fill the cooling system with water, disconnect both heater hoses and start the engine, it will only take a second to see which hose it pumps out of, so theres no chance of damaging the engine

**Sam_Q** · 11-07-2007, 07:15 PM

yeah that is true, even though I only have proper access to one of the hose ends it should give me a rough idea

**roadsailing** · 11-07-2007, 07:16 PM

post some pics, ill have a look at a RWD setup tonight if i get the chance.

things to remember:

pressure drives flow

flow goes from high pressure to low pressure

it doesnt matter that much which way you hook up the oil cooler, but i know you like wank factor so contra flow will give slightly better performance.

**parrot** · 13-07-2007, 12:12 AM

This is the directional flow diagram for a 16 valve bigport which may help. From this, as Hen notes, the pressurised water courtesy of the waterpump simply evacuates via the sensor block at the back of the head and preferentially goes through the core courtesy of the larger diameter outflow pipe when compared to the return pipe to the front of the engine.

Sorry for the poor quality however I currently can't access a scanner so had to take a photo of it. If it is useful, PM me an address and I will post it to you.

**Sam_Q** · 13-07-2007, 04:56 PM

Originally Posted by shinybluesteel

post some pics, ill have a look at a RWD setup tonight if i get the chance.

it doesnt matter that much which way you hook up the oil cooler, but i know you like wank factor so contra flow will give slightly better performance.

could you please elaborate on what you mean by this? I dont think wanting a neat factory looking job counts as wank factor.

parrot: thanks I think I will have a look at my friends fwd 4age and see how that is. Looking more at mine it really looks like the heater core is just connected between the top and bottom radiator hoses, and the only reason why water goes through it is because its parallel to the radiator and would get some of the flow. Doesnt sound right though

**DX20VT** · 14-07-2007, 10:43 PM

Originally Posted by Sam_Q

could you please elaborate on what you mean by this? I dont think wanting a neat factory looking job counts as wank factor.

parrot: thanks I think I will have a look at my friends fwd 4age and see how that is. Looking more at mine it really looks like the heater core is just connected between the top and bottom radiator hoses, and the only reason why water goes through it is because its parallel to the radiator and would get some of the flow. Doesnt sound right though

On a 20V the heater pipes are across the thermostat housing, so there is pressure there when the thermostat is closed or partially closed,
and a thermostat is never fully constantly open unless the cars cooling sysytem is not up to the task.

**roadsailing** · 15-07-2007, 01:09 AM

Originally Posted by Sam_Q

could you please elaborate on what you mean by this?

short version:

it doesnt really matter what direction the watre flows through the oil/water heat exchanger, so just mount it whatever way looks neat.

if it looks like it is hooked up in parralel to the radiator, then water will flow from the top to the bottom, as does the radiator.

**Sam_Q** · 16-07-2007, 06:19 PM

ok, I wanted to know which direction the water flower for my understanding only, I know it wouldnt matter for the unit itself. I will just choose the easiest option as you sujested.