Martin, you should pull the radiator to do the flush, or at least pull
the hoses off. Then you can back flush it and not push the debris around
your whole cooling system. Remove the temp switches and look in there,
before and after you use whatever flushing chemicals you want to try.
What you see in there may help you decide if it is time for a new one,
or time to take it in for professional help.

Mark

Poppie Jagersand wrote:
> On a couple of occasions last summer the motor temp of my 1.9TD crept up to the warning light/buzzer level. These were both on hot days and high loads (going up a backroads rocky mountain pass). With hotter temps again here in ALberta, Canada I'm thinking about what to do.
> I'm running the original 30 year old 82D radiator and it seems to be gumming up and restricting flow a bit too much..................
>