OVERHEATING

[David1965]

Well just to add further problems to my s type ownership I had an overheating issue last night which resulted in my last 1 1/2 mile journey home taking over an hour.

I looked down to see the temp gauge all the way into the red and i immediately pulled into a layby. I waited half an hour for it to cool down and then checked the coolant level which was fine. 

I managed another half a mile or so and the temp needle flew into the red at an alarming rate so pulled into the next layby and repeated the process until i eventually got home.

I remember turning the aircon off a minute or so before this happened. I recall briefly turning the aircon off a few weeks ago and steam started to come from under the bonnet,  i immediately turned it back on and this sorted it.

anyone have any ideas what could have caused this overheating issue.

 

 

[JOE-DOT-COM]

Hi David

you need also to check the temp, just in case its the temp sender,

You need to check that you fans are kicking in on the radiator

what engine is fitted to your car, as some s-types have aux pumps that improve cooling

you really need to sort this, as if it overheats fully, blowing all the water out, you can warp the heads and even pop headgaskets

if your fans are not working, it might just be that simple as fuses, fault radiator fan switch or a faulty fan

if fans are kicking in then it could be something more serious, like thermostat stuck shut, water pump or worse case sennario, head gasket can cause overheating

if your not too handy with cars, your local garage should be able to diagnose this quite straight forward

switching the air con on usually makes the car heat up quicker or overheat, if you have cooling issues, as the air con condensor is sat infront of the rad, when air con is on the   condensor will get hot and when the fans kick in, hot air is blown onto the rad, causing to overheat

cheers

Joe

[david moore]

start car and let it run, then check expansion bottle for  coolant/water, then very very carefully check the coolant hose`s with your hand (if you are confident) be very careful of fans as they may cut in?  keep a check on temp gauge in car. if it reads off the scale/red, fans should cut in on the radiator? put car heating on full and feel if it gets red hot! thats a good sign if it does. check for any onboard messages regarding. check coolant levels, check for leaks, if none? this may be sensor or thermostat or electric engine  coolant sensor on engine block. all things for you to check first, good luck.

[David1965]

Its a 2002 facelift 2.5. The fans are working and i should have mentioned that there was plenty of steam leaving the bonnet area when parked up in the layby.

My plan was to change the thermostat first or even just remove it and see what happens rather than pay out for the thermostat. Like you say it may be the pump.

 

[ay_jay]

You have not had the best run of luck with your car. Does the radiator get hot mate?  If not then I would suspect the water pump or thermostat. This may be completely irrelevant but I know that this engine was also used in the mondeo ( I had one) and the water pump had plastic impellor blades that used to fail. I stand to be corrected if this is not the case for you but wish you good luck and hope it's not too serious. 

 

[David1965]

Well I have had a look at the car this morning and the expansion tank was low on water so I topped it up.

Started the car and it came up to normal temperature with the needle in the middle, I let it run on the drive for a good 30 minutes and it held a steady temperature.

I did notice that I was not getting hot air through the driver side air vents and just marginally warmer on the passenger side.

I then took it for a drive and within a couple of miles it was in the red again. I checked under the bonnet and it looked like water had  blown out of the expansion tank cap. 

I am assuming the heater valve is responsible for not getting heat through the vents but could this cause the cooling system to fail. I did check the rubber hoses off the heater valve and they were cold, this was immediately after I stopped so should they have been hot.

Any ideas folks.

[David1965]

Will be putting a new thermostat in today but thinking about ordering  a new water pump aswell. I notice that valeo and borg & beck make them, any idea which is the best make? 

[David1965]

Ok, i've fitted new stat and got engine upto normal running temperature. The top side of thermostat housing is hot but the bottom is cold. Top hose hot, bottom hose obviously cold but the rad is also cold.

I can't see the new thermostat being jammed shut, I'm thinking I have a blockage in the rad so there is no flow.

Any thoughts on this, if so how do you unblock them?

 

[Simjag]

4 hours ago, David1965 said:

Will be putting a new thermostat in today but thinking about ordering  a new water pump aswell. I notice that valeo and borg & beck make them, any idea which is the best make? 

Can't see the point in changing the water pump, if it's faulty it would overheat within mins and you have had it running for 30 mins on your drive with the gauge staying on normal.

I hate to say it but it sounds like HGF to me, as it's fine until you drive it (load on engine) and I have seen more 2.5s that any other S engine with HGF. Sorry!

[david moore]

sounds like you are getting there, but still check water pump? also it may need a complete system flush! does them good too, as when was the last time it was done?  good luck

[David1965]

No idea when it was done if it as at all. Wha tf s the besg nethod to flush the rad? 

Keeping fingers crossed its not head gasket failure.

[david moore]

if head gasket has gone or leaking? the sign for this is undo the Oil filler cap and see if its like a creamy sluge! then that answers your problem :-(  

[David1965]

Checked the Oil cap a few days ago and it was clean. I've been back out to the car and disconnected the radiator hoses top and bottom,  and no blockage at all.

So I removed the thermostat  and bled the air and  I now have hot water flowing through the rad.

Took it for a  spin and it started to overheat again after a couple of miles although only went 3/4 of the way up the gauge.

I now think it is a water pump issue as its not forcing water through the thermostat  yet still overheats. I'm  not getting hot air but I think thats another issue being the heater valve.

Any thoughts will be helpful.

 

 

[O.T.H]

Hi --I would say you have a impeller problem with the water pump as it sounds as though the waters not circulating hardly at all.??

If it was a head gasket problem enough to cause this problem it would be over pressuring the system really bad .

Frank

[David1965]

Yes i am convinced its the pump now as i've just done the thermostat test in a pan of boling water, it opened 10mm so thats ok.

[Old Peter]

Hi David, 

My son's x type had a similar problem, but as there was a drip of water from the water pump I got my mechanic to replace it.  £150.

Regards,

Peter.

[Simjag]

23 hours ago, david moore said:

if head gasket has gone or leaking? the sign for this is undo the oil filler cap and see if its like a creamy sluge! then that answers your problem :-(  

Not always!   The gases from a cylinder can leak through head gasket into coolant (which would increase coolant temp) without going to the Oil ways.

[Simjag]

20 hours ago, David1965 said:

Yes i am convinced its the pump now as i've just done the thermostat test in a pan of boling water, it opened 10mm so thats ok.

But surely it the water pump was faulty then it would of over heated in your drive after 30 mins running.

[O.T.H]

Hi Simon I agree with you on the head-gasket but in past post's David has said the waters not circulating.???

So I think if the thermostat's oK it must be the pump .????

I would have it off and check the impellers because I'm almost sure  its plastic or nylon  blades and I have known them to fail on other cars .????

[Simjag]

21 minutes ago, O.T.H said:

Hi Simon I agree with you on the head-gasket but in past post's David has said the waters not circulating.???

So I think if the thermostat's oK it must be the pump .????

I would have it off and check the impellers because I'm almost sure  its plastic or nylon  blades and I have known them to fail on other cars .????

Well could be pump but it's hard to work out if it's circulating, fingers crossed for David it is!

But not heard of any impellers failing on any S engine before but have heard of HGF on cylinder 6 on 2.5s a few times.

[david moore]

hi david` how i you getting on with the issue of the overheating problem? and have you now got it sorted! as we have not had any updates on this problem.

[David1965]

Just had a pump delivered yesterday however I won't be able to try and fit it until Sunday at the earliest due to work.

I will update as soon as i can though.

[David1965]

Finally got back to the s type today and I have managed to get the water pump off.

The impellors move freely so I was concerned because I was expecting it to be jammed or a little stiff.

So checked the engine Oil filler cap and it was showing a little sign of milky Oil.

Then pulled out the Oil dipstick and it is covered in what looks like dirty muddy water.

Well simjag it looks like you were right after all, it appears it must now be a head gasket problem.  Check the picture 

With the dodgey autobox On top if this it looks like this car is now scrap.

[Simjag]

Oh!!  Sorry I'm right.

So you're not going to repair it then?

 

[David1965]

 if it was just  the headgasket then i would have considered it but their is akso the gearbox issue. 

I will put the std alloys on and just get rid of it.