Just after a bit of advice/thoughts really, it's not for my car - its for a friend's.... wait for it... 1996 Golf Diesel! 
Its' behaved fine over the month of snow and ice in Dec/Jan, but wouldn't start this morning, just gives a 'click' sound from the starter motor apparently, and wont turn over. Separate battery has been tried, and same problem occurs.
Could be a dead starter motor, and I've advised him to check for any leaks, oil level, possibility of piston frozen to the block? (cold night last night!)
Anyone had any experience of similar, or know what would be likely to cause a diesel to not start like that?
Cheers

Its' behaved fine over the month of snow and ice in Dec/Jan, but wouldn't start this morning, just gives a 'click' sound from the starter motor apparently, and wont turn over. Separate battery has been tried, and same problem occurs.
Could be a dead starter motor, and I've advised him to check for any leaks, oil level, possibility of piston frozen to the block? (cold night last night!)
Anyone had any experience of similar, or know what would be likely to cause a diesel to not start like that?
Cheers