Toyoace diesel not starting

[pawright]

new here so please be kind

i have a toyoace diesel it was running fine then the keys got lost so i started looking at what it might take to get a key cut to the code on the steering lock, i dissembled it partly then the keys turned up so i put it back together. the problem now seems to be it won't start, the glow plug light comes on then goes off as normal, the starter kicks in but you crank it and it does not start. it did try to start once ran for a few seconds and then died. i checked to be sure it had fuel and there is plenty of fuel, does anyone know if there is something that commonly goes wrong with the diesels i have checked fuses under the dash but they all test fine. any help would be appreciated