Hello folks.
My question to the en-lighted is this. I decided to replace both thermostats on my 2.0 diesel as it is slow to heat up and runs under the middle section and cools down when heater is on so I ordered a new thermostat and a replacement oil cooler thermostat as I was advised that this is usually the problem so they both arrived ok. My issue is that the replacement grey oil cooler thermostat lets me blow small amounts of air through it but I would have thought that this would allow the water to pass causing it to run cooler than it should on start up. The original black oil cooler thermostat when removed will not let me blow any air through it. Has anybody had any dealings with these before. I don't want to just fit it and hope for the best. I replaced the main thermostat but that made no difference.
Thanks

 

I just replaced both of my thermostats. The reason you can blow air through it is that there is a small channel inside the grey thermostat that bypasses the thermostat valve. You could install it and hope for the best (i did and it didnt work) or you could do what i did: just take the spring, the copper valve and a small needle out from the new grey one and install them inside the old black one. Its very easy to take them apart: rotate the spring out (just like you would remove a key from keyring), the valve and needle falls out by itself. When putting back together, just make sure you put the needle back correctly: sharp tip goes inside the valve and flat tip goes inside the housing.
I hope it helps!

 

Thanks Simo. I did as the seller asked me to and fitted the grey one that I could slightly blow through and guess what the temp struggled to even come out the blue section so I decided to go and buy a new original ford one with the same part number and when he brought it through in its box I took it out and guess what it was wide open and I could easily blow through it and I pointed this out he said its brand new and should be ok and that if it is not ok they will replace it so probably stupidly I fitted it and it still runs above the first mark out the cold. I look at the Jaguar repair manual and it states that the oil cooler thermo starts to open at 75c and is fully open at 89c so indeed it should be fully closed when fitting. The inside of the grey thermo is different from the inside of the black thermo so can't swap anything over. I will now need to order another one from Ford. I would have thought new parts would be correct.

Did replacing your thermostats make it run in the middle of temp gauge and stay there?

Thanks

 

I didnt fit the original parts, instead bought some aftermarket ones. Main thermostat opens at 88C and oil thermostat at 76C (measured in hot water with laser thermometer). My temp gauge stays solid on one mark below the middle line. It rises pretty quickly, about 3-4 km (2,5 miles) driving in city traffic. It doesnt cool down on idle and doesnt seem to get any hotter either. I also have an EGR blank kit installed, so i think thats the reason it runs a bit cooler.

If you have a Ford original part, could you take a photo of it and post it here? I would like to know how much it differs from aftermarket one before i buy it.

 

Hi. Not sure how to include pics but will give it a bash.

 

The numbers on the end of the copper part differ too. The original is 42 over 3D the grey one is 16 over 7B. Hope this helps

 

My car takes ages to heat up like 8 miles before it starts to move and the temp fluctuates between the large marker below the middle point and the one above the cold so the issue is def with the oil cooler thermo as different ones are giving different running temps.