Originally Posted by wpoll

Might try the suggested methods combined - drop the alarm temp setting to 100c then go for a drive with the radiator blocked by cardboard - 100c shouldn't stress my diesel cooling system overly and at least we'll then know!

Although I 'spose that not really any different than dong what Crowz suggests - setting the alarm at 85c.

I'm back at work now, after our summer break, so have less daylight hours to play with this.. But at least its warm here!

P.S. - I'm NOT actually going to stick cardboard in front of the radiator - there's too many other things up there that need air flow, like the intercooler, oil cooler etc.