Thread: Rover 3.9i and Leyland 4.4 water path

Seeing nobody has answered you they are probably as confused as I am about your enquiry.

The two stubs on the rear of the water pump are used in a 3.5 V8 for the heater. On a 3.9 One is blocked and the other goes to the heater and the heater return is on the manifold.
I have no idea why you have added 2 stubs on your manifold.

Which manifold is it? a 3.9 Efi?

If a 3.9 Efi , the water comes in the bottom hose , into the pump , which pumps it into the block. from the block there are small holes into the head on the front and rear of the block deck, from there it goes into the intake manifold , and then through the thermostat to the top radiator hose.

I do not know what you want to do with the extra pipes from teh manifold, but 1 I guess could go to the heater and use one of the stubs on the water pump as the bypass to the heater. Apparently you must have the heater in circuit as a bypass while the engine is warming.
You mustuse one of the water pump stubs or there will be no circulation in the heater core.
Regards Philip A

Originally Posted by Rokkitt

Hi,

I am looking for some clear diagrams detailing the water path through both the 3.9i Rover and the 4.4 Leyland, I am putting the 14CUX injection system onto my 4.4 - I have tapped two additional connections (5/16) to the back of the manifold and I was initially advised to connect these to the second output on the back of the water pump.
Does anyone have any diagrams that will assist??

Thanks once again in advance
Rokkitt

PS: only weeks from driving it out of the garage....

,

5/16 is pretty small, which is probably a good thing as bypass flow robs circulation from the radiator. What was the reason given for the advice.. air locks???

When you say back of the manifold, do you mean the manifold mounting face flange that blocks off the rear water outlets of the heads?