I have my xk8 in the local garage that they can't seem to find out why its over heating the car over heats when driving it a couple miles.

He's telling me its the head gasket but I'm not convinced because it runs strong and no smoke out of the tail pipe any one know what else it could be? Fans work and removed thermostat any one have a remedy? Please advise thanks cr

Hi Carl, are you certain that the car has sufficient coolant volume within the system? If running hot with no thermostat, then I would check for a coolant system blockage, i.e. radiator flush required.

This is best undertaken with the radiator removed from the vehicle. Invert the radiator and back flush. Also, back flush the heater matrix, which should be easily accomplished with the thermostat already removed.

In addition, fully check the external condition of the radiator, bent or damaged fins can also cause issues.

N6 JMX

Hi Carl

First simple things I would check is the condition / volume of the Engine oil and coolant. Are there any signs of coolant in the oil or oil in the coolant?. A lack of smoke is not always diagnostic of a failing cylinder head gasket. The smoke comes if oil / coolant is reaching the cylinder and being expelled through the exhaust. If cylinder pressure is leaking into the oil ways or coolant you should see fumes from the crankcase when you remove the filler cap or have coolant being forced out of the radiator cap.

As Jim said, it could be a blocked / leaking coolant system but I once had the AA out to a Saab 95 which was overheating on the motorway. They said faulty temp gauge as everything seemed OK. I stopped 20 miles later when temp gauge fell but by then cylinder head was already warped 😞

Good Luck

John

 

Hi did you ever get this problem resolved?