I have an L-reg Citroen Xantia 1.9 turbo diesel and want to change the water
in the radiator. It has been over-heating, but topping up with water, running
the engine and adding more water seems to have alleviated that problem.
However another thread on alt.autos.citroen <http://tinyurl.com/h6ypm this
week indicates I should bleed the cooling system when I top up the
The water already in there seems to be pretty disgusting and my father, who
has years more experience of car-maintenance than I do, can't recall ever
having seen anything like it. He has described himself as fairly shocked when
he "saw the brown muck at the radiator-cap and that deposited where overflow
had blown out of the system". There's lots of rusty-brown floating scum in the
cooling system's water tank, and the water just seems quite disgusting.
I think that ideally I should drain the cooling system completely & refill but
the problem is that I can't even drain it!!
On the Xantia there is a tap at the bottom of the radiator for draining; 60
degrees of turn it seems to be its full travel, yet no water comes out when it
is fully open. Could this be because I didn't have the bleed vents (described
at <http://tinyurl.com/l88ld & <http://tinyurl.com/q3og2 ) opened, or is it
more likely to be because the tap itself is full of crud?
Obviously if there's a blockage in the tap then - although in the long-term
I'd hope to fix that - I can get around it by disconnecting one of the
radiator hoses, and drain the system that way. What I'm wondering if there's
any treatment I can do for a system in which the water has become as nasty as
that in mine - it's the rusty-browness of the water that concerns me. Is
Rad-Flush (tm) any good for this, or is there some other treatment? I always
figured most stuff like that is snake oil, but I'm loathe to ignore what
appears to be corrosion floating around within the engine block's cooling