Dead E39 radiator? (cross post from BMW board)

[Collectingbrass]

Any advice you can give on this thread would be much appreciated

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[PaulKemp]

I certainly would not replace every part of the cooling system as posted by others.
I would look at the thermostat as that is a cheap fix.
If radiator has been pressure tested then that should be ok
Run the car up good and hot and check for leaks everywhere
The tiniest of leaks can manifest as a very fine jet or on some radiators a very slow weep at the seams
Water gets out air gets in that's when you notice the gauge gong skywards

[S0 What]

IA UV light will help spot leaking coolant, even in small amounts, it will fluoresce under UV so it's handy for tracing leaks ?