Hello all, I am having a small issue with the cooling system on my 2002 Zetec 4/4. I have just had a new alloy radiator and expansion tank fitted by Tim Ayres, amongst a load of other stuff. Before I let Tim have a look this week, I wondered if anyone has experienced anything similar.
The issue seems to be the expansion tank cap - the car runs well, gets up to temp as it should. As it gets up to around 100 degrees the expansion tank starts to fill from the bleed pipe coming from the stat, and the other one coming from the rad. So far, so normal I believe? But the cap then starts to bleed off steam, which gets quite violent until the fans kick in. At that point the level in the tank drops back, and the steaming stops. I can take the cap off at that point without issue - there is clearly no pressure in the tank. The cap itself does not seem to screw on that tight, which is something I have not encountered on other engines, but maybe it is correct?
When this initially started, the tank was venting coolant, but that has now stopped as the level of coolant has fallen. It has dropped below the MIN mark on the tank, but there is still a low level of coolant visible in the bottom of the tank - I seem to recall reading Phil Benfield advised that that was satisfactory and that the level did not need to be on MAX or even at MIN.
I am sure Tim will be able to sort it soon enough, but in the meantime and to aid my understanding of the system, does anyone have any views or thoughts on this?
thanks
Mark
