Hi All.
I have been trying to locate the source of a coolant leak. While the system holds pressure I can smell a coolant leak after bringing the Rangey into the closed garage. Topping up about a cupful every couple of months.
Poking around with the borescope I can see evidence of a weep below the radiator top hose coupling to the front of the engine as per the attached photos.
Suspect there is a O ring within that is in need of replacement. Has anyone had experience with this?.
Thanks.

Yes, that is the thermostat housing. It's fiddly but there is just enough room to pull back the top hose and the other without removing the fan. You can buy the O rings for the hoses from eBay for not very much. Whether your leak is from the housing itself is not clear. 2012 Vogue TDV8 in Aintree green over sand

Thanks for this. Will let you know how I go.

Is anyone able to identify the size of the O'Rings required to be replaced for both of these hoses? Do they need to be Viton?

Have been putting this one off and finally have time to complete.
Found this post identifying the replacement O'Rings as 45mm by 3.5mm or 4 mm.
https://www.fullfatrr.com/forum/topic66813...eplacement
Does anyone know the exact size of the O Ring and whether the 45mm diameter is the inside or the outside measurement?

If you continue to read the thread that you linked you will see that it is internal. 2012 Vogue TDV8 in Aintree green over sand