GQ 4.2 Petrol Radiator Hose

[SJC]

My car’s fan/heater “console” temp slider does not actually work. Ac is always at max cold setting, which makes me wonder then would there then never be water flowing through these two hoses? There will be water pressure in first hose going into heater but not flowing through heater into second hose going back to water pump/radiator? Not sure how the heater matrix works
The bottom hose feels softer than the one going back to radiator side...

[iandvl]

If there is coolant going into the heater matrix, but no coolant coming out, your vehicle will be over-heating.

TB45/TB48 at least. I am not qualified to speak about the TB42.

Edit: I think Mr. Connan has previously mentioned that there is always coolant circulating through the matrix, so I guess this is true for the TB42 too. Looking at cooling system schematics for the TB42, it would appear so at any rate. But I stand to be corrected. The coolant will probably only circulate once the thermostat has opened. So you can only reliably figure the pressure in the pipes out when the motor is warm.

[SJC]

...there is always coolant circulating through the matrix, so I guess this is true for the TB42 too.

Ya you right
“The coolant is always flowing through the heater core so turning the heater on simply moves a flap that directs air through the core.”

[SJC]

Found part numbers:

CF9CFC75-503D-4834-88CE-B8CC31265CA2.png (14.44 KiB) Viewed 5818 times

9240032J00
9241032J00


https://nissan-europe.epc-data.com/patr ... 278/27181/

[Peter Connan]

Just a little note:
There is no water valve in the heater system.
However, that doesn't mean that all the water has to pass through the heater.

In other words, a blocked heater core will not result in an overheating vehicle.

So the problem can be a blocked water circuit or a problem with the air valving (either electronic or mechanical).