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Car overheating

2309 Views 13 Replies 7 Participants Last post by  Jj1968
Another problem after doing my engine.

If I'm driving slow, or stopped, the coolant temp shoots up quickly towards the red and I get a "ENGINE TEMPERATURE HIGH" on the display. I quickly fire on the hot vents and go for a drive and it settles down. The fan does cut in (usually when the car is off!) but doesn't seem to run when the temperatures are approaching the high levels. I've bled the system as well as I know for a Ford (left the coolant cap off while it runs) but after about 15 minutes, the coolant starts to pour out of the bottle.

As it's a Volvo drivetrain, are there any special bleeding procedures? I noticed there's a brass nipple on one of the oil cooler pipes, but I didn't want to touch that as all I can imagine happening is the coolant emptying itself via there!
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Not bled one myself but I'd say running it for 15 minutes continuously is the wrong way to do it - obviously the longer you run it the more the coolant heats up and hence it overflows. If there's loads of air in the system you're just letting that clear but not topping up to get the level right.

I'd suggest you try filling it up, get in there and give all the coolant pipes you can reach a good squeeze then start it up for a minute then stop it, top up the reservoir, and repeat several times until the reservoir level doesn't drop any more.

Have you given the car a thorough check to make sure there are no pipes kinked at all?
when the engine is running up have you checked the coolant pipes and rad for heat,are all the pipes getting hot? Is the whole of the rad getting hot? Are you getting hot air comming through the heater?
Answer this and I should be able to shine some light onto this for you as this is pretty much what I get paid for.
Checked all the pipes and there are no kinks etc. All pipes are getting hot and the rad is nice and toasty. When I go a run the temp comes back to normal. Also the heater blows just as warm as did prior to the swap.
You dont have an air lock then in my opinion bud, I would be checking the coolant cap first then I would be checking the fan switch and the wires going into the plug (mounted into the rad)
Never thought about the coolant cap. You reckon it's not venting pressure into the right chamber ? The rad fan does kick in but only seems to when I turn the engine off
With the the cap if the seal is worn or the relief valve is knackered it changes the boiling temp of the coolant so this could be causing all the problems so try that first.
Just a thought when the engine is running does one the the main coolant hoses feel more pressurised than the other?
You weren't following the correct bleeding procedure but that may not be the issue anyway.
The correct procedure is:

1. Switch the interior heater blower off.
2. Fill the coolant expansion tank 15 mm over the MAX mark.
3. Install the coolant expansion tank cap.
4. Start the engine, maintain the engine speed at 2500 revolutions per minute (RPM) for eight minutes or until the engine reaches normal operating temperature.
5. Maintain the engine speed at 2500 RPM for three minutes after the engine has reached normal operating temperature.
6. Increase the engine speed to 4000 RPM for five seconds.
7. Decrease the engine speed to 2500 RPM for three minutes.
8. Switch the engine off.

I'm a bit more inclined to think that it's the thermostat at fault.
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Aye those are two good leads. I'll try the stat from my old engine. If it wasn't opening then would it not overheat on a run or is there a safety circuit that's just making it a bit difficult for the pump to circulate it properly?
If the thermostat is stuck shut then in a way yes it could over heat but the coolant hoses on one side of the rad will go rock solid due to the pump pressurising up to the thermstat and its very rare that you will get any heat from the heater.
Just read thread with some interest.

We have never come across this problem with any of the cars we work on (we have bled 3-5 systems per week for the last 2-3 years) - The ST cooling system is one of the easiest car to do

If the fan is running I would go with Luke ST3 suggestion that it is a sticking thermostat or a slightly blocked radiator? - keep us updated with what you find - or if you need more help give me a ring - 0161 406 9797
Hi all just fixed a similar issue temp gauge very high then limp mode changed the thermostat housing which is the second time in its life time now at 97K miles. This is a diesel PSA engine garage changed the water pump it has a plastic impeller which had fell off so engine had no flow. Check your flow in the expansion bottle.
p.s. Ford know about this issue.
No. The Mk2 Focus ST is petrol only and a Volvo engine. Are you referring to the Mk3 STD?
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Yep sorry for the confusion I noticed hardly anyone comes back with the cure this drove us mad.
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