iPod is in a constant reboot loop.
There are a few possibilities as to why the iPod doesn't work:
1) Loose HDD Cable ( easy fix)
2) HDD has failed in which case if you replace your self , HDD can be bought for about £55 on eBay..
3) Apple will swap this one for a refurbished iPod classic with a 3 month warrenty for £92..
The iPod isn't in the best of condition.