406 v6 cooling fan

Martycit · Post by **Martycit** » 07 Sep 2009, 10:26

My v6 cooling fans blasts occasionally when it feels like it usually when it hits 75 degrees, its not overheating and never goes past 80 degrees, hence the fan seems to be supercooling the radiator, it is running fine at the moment and runs better than when the fan is blasting. So thinking there was an air pocket trapped i replaced the fluid using a header tank and released air from the top of the radiator and the bleed screw on the heater pipe- is there another?? that ive missed cos the prob is still there but is fine at the moment, no leaks anywhere, no oil in water, no water in oil, could it be a temp sender or a fan switch?? I had the same prob with my v6 xantia which was also intermitant with this!!

Post by **CitroJim** » 14 Sep 2009, 10:39

Hi Marty,

I find this is pretty typical V6 behaviour in that the fans seem to come on at what seems quite a low temperature.

The bleeding of a V6 is very critical. Expansion cap off and open both bleed screws (one on the thermostat housing and one a way down the front bank water distribuituon pipe) and let it run at fast idle until the fans cut in and off, all the time with the cap off.

Final check is to make sure the rad is nice and hot all over.

If she's bled OK, I'd not worry too much..

KP · Post by KP » 14 Sep 2009, 21:06

Its possibly due to the heat build up between the banks as heat can often get trapped there can't it?

Better to be a tiny bit cool than too hot. My Activa runs at nearly 90 all the time which i feel nervous about often as its the highest i've had a car run at for a long time...

Oh and if Jim says its normal i wouldn't worry, he is the citroen dood after all

Martycit · Post by **Martycit** » 08 Oct 2009, 09:51

approx 2 weeks after posting this topic it cured itself and has been running fine ever since!!