Coolant circuit

[Jacksondh]

Thanks to CHRIS and JON1D Brilliant video from RPI. This answers my question perfectly. Cheers guys.

[JON1D]

RPI Engineering does a nice video.

https://www.youtube.com/watch?v=Ykos2Xj2Wl0

As you don't have a heater matrix your two heater hose outlets/inlet to and from the water pump are tee'd together feeding inlet manifold rear port.

[Chris]

Hi Jacksondh ,
If it's the same as my 3.9 V8, the two pipes that you mention are connected together, one pipe from the
back of the water pump, the other from water / oil pump housing are to supply the water cooled inlet manifold
and if your lucky, a heater matrix for your creature comforts !
My pipes just give a flow and return for the inlet manifold with a "u" shaped end piece that would need to be
removed if I wanted the luxury of a cabin heater .
Hope this gives you the info you need ,
Chris.

[Jacksondh]

Thanks GDCobra for your comments much appreciated, the header tank issue I have in hand. My confusion is the piping from the two small ports on the back of the pump and the fact that both are connected together, I would like to know if both ports are return to suction or is one a feed out from the discharge. I have failed to find a diagram that explains this specific point, so if anyone can answer this then it would really help.

[GDCobra]

As mentioned in the other thread, it would appear that your header tank is too low (and doesn't really seem to serve much purpose unless I'm missing something) and the thermostat outlet to the radiator is too high.

I'm no expert in this area but it would seem that the header tank is only connected to the bottom hose, there is no flow through it?
It seems like the pressure cap on this tank is the only method of getting water into the cooling system?
If so this means  you will only be able to get water in the system up to the level of the pressure cap seal face.
Once filled it is unlikely that any of the water in the pipe between the tank and the bottom hose will circulate and also unlikely that any air will be extracted into the tank.
The pipe from the bottom hose may as well just go to a filler neck with a pressure cap.  In fact that would most likely be an improvement as this could be located higher and give some chance of filling the system.
As the engine runs (with t'stat open) water will be drawn from the radiator, flow into the engine and some of the air may be shifted into the radiator but it will always stay at the top so unlikely to be drawn out by the pump hence my comment above about it being ulikely to get to the header tank.

The system is similar to mind apart from I effectively have the header tank fitted into that top hose, granted the hose does sit slightly higher than the tank (which I'm looking at remedying) but as coolant is pumped through the hose some/most of it will be carried with it, once in the tank the air will rise to the top of the tank and be extracted from the coolant which can flow through to the radiator.
As the coolant expands with heat any air captured in the top of the tank will escape down the overflow, and as this goes to an expansion tank (which will always contain some coolant) the air will escapen and be replace by the coolant in this tank.  Obviously this may take a few heat cycles but once that has happened and the engine is cool the header tank is always full when I remove the cap.

One thing which may help you in the short term would be to add a filler neck and pressure cap to that top hose, I'm pretty sure this kind of thing is available.
The first thing this would allow you to do is get coolant into the system up to the highest level.  Any air remaining would get flushed out of the pressure cap overflow and, if you also fitted an expansion tank, would allow fresh coolant to be drawn back on cooling.  This would be similar to my setup except it may take longer/more heat cycles to extract the air.

 

[Jacksondh]

https://ibb.co/VcC94GVN
https://ibb.co/DDCPDm6M
https://ibb.co/NgRB26pH

[Jacksondh]

Hi All, Trying to understand the cooling pipework arrangement, specifically to the Inlet manifold. The diagram attached hopefully shows piping (in green). This appears to common what originally would have been the supply and return to the heater matrix and then connects to the rear entry port at the back of the inlet manifold. It doesn't make any sense to me to do this. If anyone has an explanation  or better an alternative it would be appreciated. For info the T/stat housing has a bypass connection currently capped.


https://ibb.co/VcC94GVN