Mondeo overheating help needed please

[Norm]

Hi guys, need some help just got back from taking the daughters boyfriend home, the car warmed up fine and I put the heater on to demist the windows as it is cold and wet here today. Nice toasty warm air coming through the vents. 5 miles further on the heating suddenly started blowing cold air and the temp guage started rising rapidly, I pulled over and made a quick check as best I could by the roadside as it was persisitently raining, no obvious leaks, no steam, coolant in expansion tank, drive belts seem ok. let it cool down and completed the journey by stopping every few minutes to let it cool down, the temp was never allowed above 3/4 so I don't think I've cooked it, it ran fine with no loss of power so I don't suspect head gasket, I'm discounting stat as it warmed up as normal. My thoughts are water pump failure anyone second that or have any other ideas, will investigate further tommorrow as its still raining and everywhere will be shut for two days so no point in struggling in the rain tonight. Its a 52 plate diesel mondeo.
thanks in advance Norm

 

[the snooper]

forget that just seen its a 52 plate

 

[the snooper]

did you feel the top and botton hose for the temp it could be the thermostat stuck the mk3 mondeo petrol was know for dodgy thermostats but when they failed it did the opposite to yours it never warmed up enough.

 

[Norm]

Checked top hose and that was warm couldn't get to bottom hose at the time. discounted stat on the basis that it warmed up ok and I got hot air from vents, heater suddenly going cold and temp rising makes me think water not circulating? water pump splines ?

 

[Lawnmowerboy]

Sounds quite like the heater control valve sticking, exact same thing happened to mother's festa...

 

[Norm]

Sounds quite like the heater control valve sticking, exact same thing happened to mother's festa...

did that cause her engine to overheat?

 

[mike 109444]

Did the rad fans come on? If not then even though your temp gauge is showing high that hot water is not getting to the rad to try and cool (and thus setting off the fans) As you say could be the pump but also could be the thermostat. As the stat stops water circulating through the rad and also the heater it would be my 1st item to replace, cheeper and quicker than pump. Hope you get to the bottom of it cos my brother has just got slightly older version of the diesel mondeo. Don't think you can leave out the stat in moderen cars like you use to be able to cos I think there is a o'ring that forms the seal with the stat... gerrr moderen cars

 

[Norm]

Yes rad fans came on, presumably they're triggered by the the temp sensor.

 

[Fazerruss]

Checked top hose and that was warm couldn't get to bottom hose at the time. discounted stat on the basis that it warmed up ok and I got hot air from vents, heater suddenly going cold and temp rising makes me think water not circulating? water pump splines ?

The job of the thermostat is to stay closed so to speed up the rate in which the engine reaches normal temperature then open to allow normal cooling. The fact that the engine gets warm does not discount the stat only it suggests it is probably stuck closed.
If not stat then check water pump pulley for play or noise. Water pump failure starts with the seal giong then water gets into the bearings and knackers them up then causing the fins to get smashed and result is no coolant circulation.

 

[squirrell25]

there are two thermostats on the mondeo diesel if you go the the ford wiki website it will show how to change it

 

[Lawnmowerboy]

Another reason you can't take the stat out of modern cars is because it will put the fuelling out and make it run richer (warmup cycle) for longer thus using more fuel

Yes on the festa then got about 2 miles and heater stopped working and began to ran hotter and hotter so she stopped and let it cool thankfully when she got it home i stripped the heater control valve (a 2 way sliding solenoid valve) and the plunger was stuck in the middle blocking all the water flow from the head and that's where the temp sensor is located on it.

Explore the simple things first and dont go repacing parts until you have done your best to test them

simply test a thermostat by putting in a jug/jar of really boiling water (it should have the opening temp on there)

 

[the snooper]

i doubt very much it will be the water pump usually sudden loss of heater is due to sudden loss of coolant

 

[drivewasher]

It will be the water pump it's on the near side and is mounted on the back of the powersteering pump. It's driven by a female spline on the p/s pump into a male spline on the water pump. It's a common problem on mondeo's transits the splines in the female pump gear strip reulting in overheating after a few mins running.
You won't cook the engine as it will stop when the cyl head temp sensor (behind the p/s drive pulley on the end of camshaft) detects an overheat and shuts the fuel off.

Here's the spline driven pump you need http://www.ebay.co.uk/itm/MK3-Mondeo-2-0-Diesel-Water-Pump-Back-Housing-2000-2006-/390424769185?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AMondeo&hash=item5ae72132a1

 

[Norm]

cheers guys, I'm very much inclined towards the pump, and drivewasher has reinforced this, as have also now the guys on the talkford forum. I'll let you know the outcome thankyou all for taking the time to respond, much appreciated.
Regards Norm

 

[Country Joe]

Some days you're the dog ....... some days you're the lampost!

One of those "lamp-post" days, then.
CJ

 

[Norm]

Some days you're the dog ....... some days you're the lampost!

One of those "lamp-post" days, then.
CJ

Tell me about it, just had 4 new tyres for MOT never mind must be a dog day coming soon

 

[Norm]

Back on the road but bloody expensive

Just thought I'd update this, spent the day at my mates garage and I'm now up and running again, the car hadn't lost any coolant whatsoever, stripped it down and the splined male shaft on the water pump that is driven by the power steering pump had worn, the female socket on the power steering pump had worn internally and was round rather than grooved. So the steering pump was revolving but not driving the water pump. so a new water pump and power steering pump were in order, now just to make it more expensive the oil cooler thermostat which needed to be transferred to the new water pump had a cracked lip and goosed O ring so a new one of those was sourced and whilst I was at it I replaced the main thermostat as well. So now it warms up lovely, toasty air from the heater and I'm skint! with three weeks to the next payday Roll on the dog days
Norm

 

[Robotstar5]

So now it warms up lovely, toasty air from the heater and I'm skint!

But it's the middle of summer!

 

[Norm]

Must be, its pi**ing down here