Saga so far.   First it had a small leak from the thermostat housing.  Some twerp decided to dose it with "leak-seal," instead of dealing with the leak properly.

When it subsequently over-heated it was taken to a very competant colleague who replaced the stat, sorted the leak and, when it still boiled, replaced the rad.

All was re-filled, tested and seemed well until it turned-up again two weeks later; still getting hot.  In the car was a sizeable bill from a distant Ford dealer after going in for no heater..  They'd replaced the thermostat housing and stat [again; only £64;] fitted a new header tank and cap; replaced the heater's motorized valve; charged the customer a small fortune and still it boiled when driven.

It will idle all day long with the [CAN networked] cylinder head temp sensor reading about 112C.  Try and drive it though and it will hit 130C plus inside a mile.  The fan will then cut in; but blowing cold air - even though the heater is boiling hot.  Only running the heater fan will cool it enough to cut the rad fan out.  The rad hoses are not that hot; the heater hoses and the h/tank return vent hose are searing.

Today it got a new CHT sensor [it's plastic had been broken]; a new plastic-impeller waterpump and all the hoses checked.  Unfortunately, it's still no better.  I've just heard that there's a known problem that affects this particular style of 1.6 Zetec in the Focus that leads them to be a pain to bleed-out after re-filling.

Anyone come across this and know any tricks to ensure the thing is fully filled.  It's been giving trouble for over a month now; so I'd have thought that it would have bled itself - wouldn't it?

.

As for bleeding its self not necessary so. Air can get lodged in the system. i,m Sure you have gone around the system with 'your heat gun' are you sure the themostat is seated correctly.

Kevin.

"If you dont KNOW how it works, don,t try to test or fix it"

It's very difficult to find anywhere to get a clear shot at any cooling parts with the laser.  It's definitely not circulating correctly; I'd have hoped that the dealers would have checked that the second replacement stat was the correct way round before they fitted that expensive complete housing/stat assy.  The water level hasn't gone down since it was filled by the dealer and it's never actually spewed-out water in extensive local running since; despite often getting very hot.

Do you know of any special procedures to ensure complete filling on these?  There's two return hoses; one from the rad and one from the block - both are clear and there's no restrictors in the header tank stubs.

.

Disconnect the highest hose in the coolant circuit. Fit an old antifreeze bottle or something similar to the expansion tank, with a suitable seal to form a "header tank" Fill this up to the brim and squeeze all cooling system hoses, starting from the bottom up.

Leaving the highest hose only pushed on it's stub slightly, run the engine and keep squeezing all hoses, while keeping the "header tank" full. Ease the highest hose off it's stub periodically to allow air to escape. When no more air escapes, refit the hose.

Stop engine, top-up and see if this makes any improvement.

Chuck


To help and to serve

i think it might be worth while investing in a valeo fast fill there not that expensive and will make sure there is no air in the system

martin

i have decided to give up fags due to people taking the piss as to whats in them

Martin is obviously a braver man than me to suggest that you spend money on anything other than a bottle of vintage Dot.1 (The single variety is in my opinion superior to the blended variety of the latter and higher numbers!)

However I would say that we invested in a cooling system filler, very reasonably priced and unusually; metallic rather than plastic. (Purchased from SnapOn). Sine then I have solved a couple of "air lock" problems for other garages that could not bleed the air out of the system.

From your description it does sound like a flow problem, have you tried the pressure washer up the hose flushing method to get rid of all the poo in the system?

The only other thoughts that springs to mind are:

• What is the antifreeze situation? Do not forget that antifreeze lowers the boiling point of the coolant at high concentrations - is it simply boiling and causing the air lock?
• Is the combustion temperature affecting the situation when driven either by a weak mixture or incorrect timing that is not apparent at idle - again boiling.
• Have you checked for head gasket failure - may be FUBAR after all these boil ups and again giving you boiling / pressure problems. Can you fit a pressure gauge to the cooling system?

TopGun.

www.ivesgarage.com

I did once have someting similar with a K series Rover. The car would idle fine, but overheat at high idle, with, like yours, a cold rad. Turned out the engine water jacket was blocked up with "Bars seal"


Regards Tony

"One advantage of a bad memory, is that you are always meeting "new" people....."

I have just had a thought.....................I bet I know what the problem is.

The cooling system is not filled with distilled water!

Sorry felt a silly moment come on there,I will go back to the Pug 306D that has just been towed in as a no start.

Sorry , very sorry, no really really really spectacularly sorry. Feeling less silly now, well just little bit silly, nearly normal in fact, diesel no start go fix (yes boss!)


Regards,

TopGun.

www.ivesgarage.com

You pi55 taker you.

I have heard very good things about these cooling system re fillers. I think they plug into the compressed air systems found in our workshops (Angus you may have to turn your pressure up a little, if finances allow) . I am told that the evacuate the system of air & then suck the coolant in, ridding you of any air locks. My aircon bloke swears by it.

Dave

Dave Hill

----------------------------------------------------------

Life throws many curved balls at you!
I don't know whether I need a good helmet or a bigger bat!

they are really good but i am not sure if a charity will be able to afford it

martin

i have decided to give up fags due to people taking the piss as to whats in them