my "freebie" series 3 wont crank any help?

Hi all im a defender owner who has just become the owner or a 1981 diesel series 3 (a freebie off someone i know) .its been sat for 4 years. tryed to start it a couple of weeks back and had nothing so i whipped off the starter motor cleaned up and checked it with jump leads , worked a treat !!

Refitted it and tried to turn it over today -Nothing !!! The only thing i get is a clicking on the dash from a silver looking box ( may be a relay)

What im not sure of is what this box is ,and if the problem is that the solenoid on the side of the starter motor isnt getting any power to it so not powering up the starter motor.
Am i right in thinking that the last postion on the key turn should power the solenoid? With a half turn after this heating the glow plugs?

Any help would be good this is new to me !!

check solenoid feed on ignition switch white and red i think as you said then follow wire thru to starter

cheers james i thought that may be the problem , i think i need to get a newer battery on there too as i wasnt getting much light on the red glow plug heat light .

obvious question....is the rest of the motor free? Can it be turned over using the crank bolt?

The heater plug lights on series tend to be a bit dim anyway.

cheers for all the advice lads, just a update on the old series 3. i sorted the wire problem just a break in the wire, and then it started on the second turn of the key !!!!! the last time it was started was 2000 , so the diesel was 11 years old !!! got to love british engines and only one indicator bulb was out !!!