main fuse box engine fuse link

[300 henry]

someone help my 100a fusable link in the engine fuse box keeps frying what could be the problem. doing my head in. i thought it might be the  heater plug for the deisel.

its a disco 300 tdi

[Range Rover Blues]

I found ours had corroded so I fitted a 30 amp maxi fuse, but it only seems to run the glow plugs anyway :-k

However, if your fuse keeps blowing then you have a short to ground, possibly a frayed wire or a short circuit glow plug like you said.  You should check the resistenace of all 4 glow plugs and also you can check the fused side of the fuse for a short to earth too, though it may be intermittant.