Ford Fiesta (1995 - 1999) - 97 1.3 cold heaters even with hot coolant

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Thu 5 Nov 2009 10:36
97 1.3 cold heaters even with hot coolant - Dac84
I've recently replaced the thermostat as the temperature wasn't getting up to half way and it would start to overheat in traffic etc. The temp gets up to half way quicker but now the heaters go cold as (I imagine) the thermostat opens up as it is coming up to normal temp.

I know the heater control valve is the first port of call, but I've checked the hoses going in and out, both of which are hot and the same temp. I've removed each hose to pour water in and it flows through with no issues. I noticed yesterday that the bottom rad hose is hot near the engine but cooler near the rad.

So my question is - is there an airlock in the rad or has the water pump given up? I mentioned the pump because when the engine is revved the coolant in the header tank doesn't move, whereas on previous cars ive had, the level will drop with the revs as I understand it is supposed to.

Thanks in advance for any help!

Edited by Dynamic Dave on 05/11/2009 at 12:34

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Thu 5 Nov 2009 13:43
97 1.3 cold heaters even with hot coolant - piston power
You may have crud in the matrix so it's blocked or just a simple bleed will cure it, you say you have checked the valve it's working ok?

The water pump would make it overheat if faulty like the impeller has sheared off.
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Thu 5 Nov 2009 14:17
97 1.3 cold heaters even with hot coolant - Peter.N.
If both heater hoses are hot then water must be flowing through the matrix, does it have a flap that controls the air mix?

The bottom hose being cold at the radiator end is normal if the thermostat is OK. You will need the engine to be running at full power for some time for the bottom of the radiator to get warm.
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Thu 5 Nov 2009 14:42
97 1.3 cold heaters even with hot coolant - Dac84
Water is definitely flowing through the matrix as i removed the 'out' hose and poured water in via the 'in' hose, all was running through clear.

Im not sure if it has a flap that controls the mix. From reading, I think the heater valve controls the mix, which is controlled by a pulse sent from a control unit rather than manual flaps.

Just to make sure, what is the correct procedure for bleeding this type of fiesta? There are no bleed valves and i've read they can be a pain to bleed properly.

Thanks for your replies so far.
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Thu 5 Nov 2009 15:31
97 1.3 cold heaters even with hot coolant - jc2
A 97 will not have a flap type(air blend) heater;it'll be water-valve.Once you have the system running correctly-the valve has a bleedhole in it so that hot water can get back to the engine even when valve is shut.These engines are about the simplest to bleed-just put heater on full hot and run engine at about 3,000 revs for a minute.

Edited by jc2 on 05/11/2009 at 15:33

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