fitted a new halfrauds thermostat to my 2004 1.8 tdci 2 weeks ago after developing a leak at the thermostat housing. cured the leak but now the temp does not seem right. it takes about 10 mins(8miles) for the gauge to enter the normal temp range but when i put heater on, it drops right down. the top radiator pipe is hot and coolant is pumping back into the expansion tank.

could i have trapped air or a duff thermostat.i did have the front of the car on ramps when i refilled the system with coolant.coud that of trapped air?

another thing i noticed was the thermostat in the car did not have an air bleed valve which according the the haynes manual it should of. the new one has.

any advice would be much appreciated.

cheers ray

sounds to me like the new thermostat isnt right, I have only ever changed one on a mk2 1.8tdci, which didnt have a bleed valve - ford supplied me with a thermostat with a bleed valve but it didnt fit but they did get the right part eventually.

i think you would be better off getting a ford thermostat. the one i bought wasnt too expensive either

ide get the right thermostat as steff said sounds to me like its open all the time thats why theres no heat getting through you have warm coolant gooing straight to the radiator. to check for air the easiest way is get the car up to temp then slowly remove the expansion cap put the heater to hot and face and rev the car at 1500 rpm for about 5 minutes the air freom the heater should be hot replace the cap and try again.

when filling the coolant ford dont fill through the expansion bottle they remove the lid and take the small hose off the expansion tank and fill through there

Also squeezing the hoses when the engine is running will help remove air

thanks for advice

let us know how you get on it will help others

did not replace thermostat in the end. been out in another ford focus diesel and it seems to take as long to warm up as mine does. so gonna hold off for a bit.