Hard starting ZD30 Di

I’ll put this up in case anyone else ever has the issue. I was having cold start issues with my 3 ltr ZD Di, which had me thinking glow plugs, but the problem was intermittent. On Sunday I finally got to pull the intercooler off and check things out. The relay and connections seemed ok and the voltages at the relay were also OK with the plug and socket to the glow plug bus bar disconnected. I was just getting to the head scratching stage when I discovered that the nut securing the glow plug bus ( the bit of metal with holes drilled in it to connect the plugs together ) on the second plug was loose. This nut had become slightly loose and allowed the current to arc underneath the bus bar. This had eroded the nut and caused more arcing and erosion which had eventually resulted in high resistance joints, hit and miss operation and increasing erosion. Cleaned everything up and reconnected all the wires and all is good.
Cheers Tony