Car was fine till 2 days ago. Noticed fan overrun on switching off,  for a couple of minutes. Checked coolant took a couple of litres, never needed more than a cup before on monthly checks. Car has done two 25 mile runs with no problems except the heater only throws out warm air, it was hot before. 

Help. Des

It's a mk 2 not 3

How much do you pay to insure your Mk2 Focus ? 🤔

18 hours ago, unofix said:

How much do pay to insure your Mk2 Focus ? 🤔

76 per month

19 hours ago, Des Barron said:

Car was fine till 2 days ago. Noticed fan overrun on switching off,  for a couple of minutes. Checked coolant took a couple of litres, never needed more than a cup before on monthly checks. Car has done two 25 mile runs with no problems except the heater only throws out warm air, it was hot before. 

Help. Des

UPDATE

Did 12 miles today arrived with steam and temp gauge reading too hot. Engine didn't seem overheated. Drove really well. TREAT ME LIKE AN IDIOT. I remembered having a RR Shadow and after a coolant change it kept overheating till I found out that the Shadow needs to be filled with coolant very slowly. So I refilled the focus very slowly waiting for the bubbles in the overflow tank to stop, it took much more. As a temp measure I used water. Car drove 12 miles no problem, gauge normal, no fluid loss, the heater is now blasting out hot air.

The engine runs beautifully with clean oil and no filler cap gunge, even tickover so I think it's not likely a head gasket fault.

I remind that I am 78 and homeless so my thinking is addled. 

How's this for a scenario. I forget to check coolant level and by use it gets very very low. This causes the initial problem and if I refilled the coolant properly the problem would have gone away. Does that make sense. 

Lastly I now have water instead of coolant. Can I syphon of a couple of pints and replace with 100% antifreeze or do I have to drain and replace? That assumes the problem was as per my scenario. 

Thanks for any help 

Loosing coolant is definitely not normal.

First you should check for coolant leaks. Possible causes of coolant leaks on the Focus MK2/MK2.5 Petrol engines are:

* Coolant reservoir.
* Coolant reservoir cap (defective overpressure valve).
* Thermostat housing.
* Water pump seal.
* Heater matrix.
* Heater matrix O-ring seals.

If there are no coolant leaks the most common cause of the coolant loss is a defective head gasket. A head gasket can basically fail in different ways:

* Leakage between the cooling channels and the oil channels.
This kind of head gasket failure results in coolant in the engine oil which is usually identified by a white/tan discoloration of the engine oil. Because the coolant is pressurized it is easier for the coolant to be transferred into the lubrication system than it is for the engine oil to be transferred into the cooling system.

* Leakage between the cooling channels and the cylinder.
This kind of head gasket failure results in loss of coolant and is not always easy to identify since the coolant that enters the cylinder is simply burned. If the leak is small (which is usually the case) the engine can still run fine without any symptoms. 

The fact that there seems no coolant entering the lubrication system does not mean that the head gasket is fine


The cooling system contains approximately 8 to 9 Litres of coolant. When draining the cooling system through the petcock valve at the bottom of the radiator about 40 to 50% of the coolant remains in the system. Both the heater matrix and part of the engine block do still contain a considerable amount of coolant when drained.

In my opinion adding water to the cooling system is not the best idea since it will dillute the coolant and part of it will still remain in the cooling system after draining. Compatible G12+ coolant is quite cheap and widely available. 

Another point of concern is that these engines can be a pain to remove all air from the cooling system. The only way to avoid this is by vacuum filling the cooling system.


I recommend to perform the following actions:

1. Have the cooling system both pressure and vacuum tested to to identify if there is a leak or a more serious problem.
2. Fix the leak or problem.
3. Drain the cooling system.
4. Vacuum fill the cooling system with fresh coolant.
5. Run the engine for an extensive period (use the car for a few days for example).
6. Drain the cooling system again.
7. Vacuum fill the cooling system with fresh coolant again.

7 hours ago, JW1982 said:

Loosing coolant is definitely not normal.

First you should check for coolant leaks. Possible causes of coolant leaks on the Focus MK2/MK2.5 Petrol engines are:

* Coolant reservoir.
* Coolant reservoir cap (defective overpressure valve).
* Thermostat housing.
* Water pump seal.
* Heater matrix.
* Heater matrix O-ring seals.

If there are no coolant leaks the most common cause of the coolant loss is a defective head gasket. A head gasket can basically fail in different ways:

* Leakage between the cooling channels and the oil channels.
This kind of head gasket failure results in coolant in the engine oil which is usually identified by a white/tan discoloration of the engine oil. Because the coolant is pressurized it is easier for the coolant to be transferred into the lubrication system than it is for the engine oil to be transferred into the cooling system.

* Leakage between the cooling channels and the cylinder.
This kind of head gasket failure results in loss of coolant and is not always easy to identify since the coolant that enters the cylinder is simply burned. If the leak is small (which is usually the case) the engine can still run fine without any symptoms. 

The fact that there seems no coolant entering the lubrication system does not mean that the head gasket is fine


The cooling system contains approximately 8 to 9 Litres of coolant. When draining the cooling system through the petcock valve at the bottom of the radiator about 40 to 50% of the coolant remains in the system. Both the heater matrix and part of the engine block do still contain a considerable amount of coolant when drained.

In my opinion adding water to the cooling system is not the best idea since it will dillute the coolant and part of it will still remain in the cooling system after draining. Compatible G12+ coolant is quite cheap and widely available. 

Another point of concern is that these engines can be a pain to remove all air from the cooling system. The only way to avoid this is by vacuum filling the cooling system.


I recommend to perform the following actions:

1. Have the cooling system both pressure and vacuum tested to to identify if there is a leak or a more serious problem.
2. Fix the leak or problem.
3. Drain the cooling system.
4. Vacuum fill the cooling system with fresh coolant.
5. Run the engine for an extensive period (use the car for a few days for example).
6. Drain the cooling system again.
7. Vacuum fill the cooling system with fresh coolant again.

 

On 10/11/2024 at 10:48 PM, unofix said:

How much do pay to insure your Mk2 Focus ? 🤔

76 per month

Many thanks. 

Very helpful.

The water was just while I found the problem. 

One last question. No visible leaks whilst I realise it could be a headgasket I have done 24 miles and an overnight stand with no fluid loss.

Does that tell you anything?

A million thanks.

Des

1 hour ago, Des Barron said:

76 per month

Now 36 miles not a drop of coolant lost.

I forgot to say after the first overheat I used Radseal. Did it work?