General 1.9JTD still over heating after new thermostat!

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General 1.9JTD still over heating after new thermostat!

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I have a mystery with my Punto 1.9JTD, other day I had over heating my gauge needle was reach near the red mark. I have fitted a new thermostat and drove I wasn't expected the gauge went up near red line again, the fan has come on up to 30 seconds then stop. Furthermore, I have fit new water pump still over heating, what else to look for? I have noticed the climate control when is on max warm it blows cold air am I expect there is block somewhere, but the hose is quite big it can't be blocked????
 
An airlock can cause overheating and sometimes results in cold air from vents and a cooling fan that is confused on what to do as the temperature sensor sometimes picks up the air temp from within the engine rather than the coolant temperature. Ensure there's no air in the system by bleeding any air out but do be careful. There are elaborate guides on this so do have a read before attempting to purge the system.

Since you've had the issue before replacing the parts, there could be a blockage most likely in the radiator or heater block. How does the antifreeze look? If it's dirty then a flush may resolve the issue. Other issues may be a fault with the cooling fan and/or temperature sensor.

Edit: Cooling systems can block quite easily despite the large hoses. In my experience, the culprit is usually the radiator.
 
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An airlock can cause overheating and sometimes results in cold air from vents and a cooling fan that is confused on what to do as the temperature sensor sometimes picks up the air temp from within the engine rather than the coolant temperature. Ensure there's no air in the system by bleeding any air out but do be careful. There are elaborate guides on this so do have a read before attempting to purge the system.

Since you've had the issue before replacing the parts, there could be a blockage most likely in the radiator or heater block. How does the antifreeze look? If it's dirty then a flush may resolve the issue. Other issues may be a fault with the cooling fan and/or temperature sensor.

Edit: Cooling systems can block quite easily despite the large hoses. In my experience, the culprit is usually the radiator.
I have put fresh anti-freeze after installed thermostat and water pump. I have look on website my is auto bleeding but if the radiator is blocked, can the additive clean up the clot? Likewise, I don't want to remove the radiator it is a big job because I have air conditioning radiator as well.
 
can the additive clean up the clot?
It can do. Add some to the system and run the car for a few miles taking care not to overheat it. Flushing the system is a good first step.

Did you add the correct level of coolant which is 6.2 litres for the JTD? When replacing parts and refilling, you'll never be able to add that much back as there is some air in the system. I've found that lifting the front of the car while filling helps purge all the air. Also, as obvious as it is, having the exact quantity of coolant needed helps.

Also, to confirm, there's no head gasket related issue such as excessive smoking, milky oil or coolant loss? Some people use that head gasket repair bottle which does work for a short while until it clogs up the cooling system and causes overheating issues etc.
 
Yes the coolant is fill up the max mark on tank, it did not go down after drove 10 miles. I am sure there is air trap somewhere. And by the way I have posted on other forum about my exhaust is grey smoke when the engine is not full warm near at 3,000rpm once it fully warm the smoke go away the person has confirmed is normal for diesel I am not sure if is relation to coolant problem like head gasket leaking.
 
I suspect my head gasket is leaking, because there is so much bubbles, I can hear gurgle, the auto bleeding feed pipe continues bubbles forever it won't stop, I have found other bleed valve near the central heating still not improve. Anyway, thanks for little help.
 
I suspect my head gasket is leaking, because there is so much bubbles, I can hear gurgle, the auto bleeding feed pipe continues bubbles forever it won't stop, I have found other bleed valve near the central heating still not improve. Anyway, thanks for little help.
Gurgling sounds can be a sign of an airlock however given the miles of your car and bubbles from the tank, it could be a head gasket. Many ways to narrow down a head gasket including kits being available to buy that screw onto the coolant tank.

All the best!
 
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