Oh. My God.
No amount of research could prepare me for this job.
So it turns out the Dual Coolant Control Valve (DCCV) for the 2.7d is NOT in the same place as the petrol models. It is far, far worse.
I drained the coolant (after much searching for the drain point - about 6 inches forward of the circular gap in the splash guard), and removed the coolant reservoir and a few hoses to access the area behind the radiator where I thought it would be. No sign of it.
Tried removing the front splash guard to take a look from underneath. All torx screws corroded and impossible to remove. Tried removing the front bumper in its entirety, but experienced the same issue.
After much swearing and scraped knuckles I finally found it; jacked up on the front right side (and secured with an axle stand under the proper point), removed the front right wheel and wheel arch liner - and there it is! Underneath the windscreen wash reservoir.
The person that designed the location and mounting for this valve needs shooting. Removing the bolts that secure the front splash guard to the main under tray will help a little bit, but not much.
A few tips for the unwary:
1. Even after you have drained the system, be prepared for a lot more coolant to escape from the valve and hoses once unfastened.
2. Don't try to use mole grips to move the constant tension hose clamps. It will work, but it is very, very difficult due to the tight space and awkward angles in this area. You are much better off using a purpose-made tool.
3. Use a purpose-made tool to remove the hoses from the fittings. It will save you hours of sweating and swearing. And just be patient with the electrical connector, there is a knack that is impossible to describe.
4. The DCCV for the diesel models is NOT secured with a 10mm bolt as with the petrol models. It is a T27 torx screw, and the head is on the far side of the fitting. Don't try to remove the "nut" on the side facing toward the right of the car, it is welded to the mount as a receptacle for the torx screw. Only took me 2 hours to figure that out... Use mole grips or similar to hold the old DCCV in place while you wrestle to undo the screw, or you will bend the ridiculously thin mount.
5. Silicone lubricant spray is a must to get the hoses back onto the new DCCV. It also helps in sliding the constant tension clamps back into position.
I hope this helps any other 2.7d owners that dare attempt this task themselves. Using the right tools and knowing where the DCCV is on this model will save you a great deal of frustration.
