Thanks Andrips and Vmaxxer

 

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SPENT £450 having the Air con fixed 2005 Crd 2.5 ?
Driven to Spain and after 100 miles temp gauge started to rise ,Whack off AIRCon ,eased off the throttle and cabin heater on, temperature stable .
Up hills and labour the engine ,up goes the needle .
So arrived , thought I'd empty coolant ,flushed her out ,refilled coolant with new 50% good stuff . Still does it😡 Goes up to near the Red on gauge up hills with AIRCon running. My question is if I fit this Thermostat Mod ,will this solve my problem . Any help much appreciated as I'm in Spain ,and a bit stuck 😒

 

I do believe that broken thermostat would not warm up the engine so quickly. If it's overheating then you may have some blockage.

There is a small chance that your thermostat stuck on close position, then fitting the second one will not help.

How quickly the engine warms up from cold?

 

Check out the temperature sensor, it's may become loose and you are getting the false readings.

 

Agreed, the thermostat failure mode is full open, so it would cause the car to stay cool rather than hot.
If it's getting too hot, then yes conclusion is the system isn't cooling correctly, so back to normal checks:
* Fans running/working (Both of them)? - Turn on air con and check as they should both come on immediately when air con is engaged
* Blockages as Andrips says - difficult to find/locate/confirm
* Temperature sensor (Again as Andrips says) Temperature sensor location:

 

Thanks will be able to have another go later, interesting about the sensor , as I had the pipes replaced under the air box for the AIRCon ,in that area, so I'm intrigued .
Just a quick note , as it laboured up some steep mountain roads I watch the temperature run up , once stopped , I could smell that hot engine smell you get of warm moisture.
Will check the fans , I've heard them come on at temperature but never tried with the AIRCon switch on .
The other thing is if the AIRCon mechanic ,drained down the system ,could I have air in the system not allowing the thermostat to open fully.?
Would the highest point be the pipe which is connected to the thermostat housing as the bleed point at the rear of the engine ,after removing the engine cover I can see the pipe?

 

I do believe you don't need to bleed the system. Must bleed itself after few miles.

I would check the sensors and wiring.
Check if the fans are running as Andy says,if they are then the sensor.

 

Yes you are right about that short pipe or hose onto the thermostat pepe. What to do to bleed the air, is slacken off one of the hose clips completely, then prize a very thin screwdriver inbetween hose and thermo housing on the top, till air is expelled and coolant comes out. Job done no air in coolant now. Top up res tank and be surprised on how much it takes

 

I've just been reading some of the postings to my thermostat mod. So surprized I got a 5-star award for something so simple.
Re. overheating --
The usual cause of overheating is a blocked radiator, caused by the antifreeze/anticorrosive not being replaced after 5 years use. The rad. is aluminum and needs HOAT antifreeze. Once it's corroded, you cant fix it by flushing. But you CAN test it yourself: Disconnect the top and bottom hoses from the rad. (saving the antifreeze if new) and blow down the top hose connector to the rad. after cleaning off any dirt. There should be practically no resistance to your breath. If there is any noticeable resistance, regrettably you will have to replace the rad., there is no alternative. You will also find the thermostat is jammed open, they are designed to do this in over-temp. conditions.
By not changing the HOAT antifreeze/anticorrosive at the specified time (in my case a previous owner neglect) you are landed with a £500 bill instead of £40 for the HOAT*
Moral of this story? Treat antifreeze replacement as vital as changing an old cam-belt on mileage. At least fitting a thermostat in the top hose will halve that big bill.
Leedsman.
* HOAT = hybrid organic antifreeze technology.