406 Coupe Water problems!!

Hi All, this is my first post, looked around the site for help on problem
with my car but can't find anything relates to it.

Basically just bought a 406 Coupe SE 2.0 X reg, and within one week steam
puring out of bonnet, Water levels depleating almost straight away and
heater obviously won't work.

Took it into a Garage and the radiator was rotten so had new one fitted,
seemed to be problem solved, heater worked fine, no more steam puring out
from anywhere.

But few days later heater stopped working (was eratic - cold warm - cold
-warm), and the water levels were low again. I cannot see any leaks and
there is no amount of steam that i can see coming from the exhaust where
water could be getting lost, and when i filled water tank up again the
heat worked again.

Car drives like a dream, but there is obviously something pretty wrong
here...

Can you suggest anything that could be wrong, as if i take it back to the
garage i think they will try and stitch me up!

Thanks very much

James

 

Try a search of the group under 'overheating' and there are other tags
you could use. There have been dozens of posts on hot water problems.

 

If this happened soon after the radiator was replaced maybe the garage just
didn't bleed the cooling system properly. They are notoriously difficult to
bleed and require a special technique to get all the air out.

Keep an eye on the coolant level and see if it doesn't settle down. If it
requires continual topping up over a long time period then maybe get it
pressure checked or checked for a leaking head gasket.
I wouldn't be so concerned about the heater but worry about potential
engine damage. Engine cooling is the radiators primary function and the
heater is a secondary function.

Ryan

 

Ok, so I will keep an eye on the levels and if it still needs filling right
up every day after a couple of weeks then I will get it checked out

Thanks very much for your help!

 

Haynes says that a header tank has to be used to fill the system as parts of
it are higher than the filler cap. They suggest making one by cutting off
the top of a plastic drinks bottle and sealing it in the filler neck.
Failure to do this will result in air locks.

 

Well, yes; but in general a heater suddenly going cold can be a very good
indication that the water has stopped circulating for one reason or another,
so should be regarded as an early warning signal. Especially when you add
in the fact that water temperature gauges only work properly when the sensor
is surrounded by water. OK, they will tell you the temperature of the air
around them, but that won't give you much of a clue as to what is going on
in the hot bits of the engine until it is too late.

Ron Robinson

 

Sounds like it hasn’t been bled properly. I would strongly reccomend
getting it bled fully before using it, if there is alot of air in
there you risk overheating and damaging the head gasket and head.

 

Ron, I agree with what you're saying it can give an indication but I would
hardly recommend to someone (particularly inexperienced) to check if the
cars heater is working to find out if it's overheating, or out of
anti-freeze, by then it may be time for new engine.
On the 406 there's a bleed valve on the heater union just before it goes
into the cabin, ie the high point in the system that's most likely to have
an air pocket. So if the heaters not working it probably means the system
hasn't been bled.

I bled my cars system (according to the Haynes manual) after I replaced
the thermostat housing but I still had to top up a few times before the
level remained constant.

Ryan

 

Well over the weekend i Bled the system and left the engine running with
the hood up so i could see if any water was spewing from anywhere. It
turns out that i had a faulty header cap and the water was streaming out
of there and subsequently sucking air back into the system!! £6 on a new
cap, job done! thank f@%k for that! thanks for all your advise, and i
shall be back on when next problem occurs!