Checking water temp Senders?
 

I'm trying to fix an Over fueling problem with an FD, i'm 80% sure its the Water Temp sender for the ECU on the back of the water pump housing.

So i've had a look round here and found one of an old engine (that was working when it came apart nearly two years ago) is there any way of checking it before i fit it ?

Any help would be Appreciated.

Cheers
Chris