As per title really, a 2 litre diesel starts on the button, runs like a dream, plenty of grunt for a diesel but once it's hot it doesn't want to re-start if it's left for more than 5 minutes, you have to leave it for an hour til it's cooled down. I suspect the under bonnet fuel pump, the in tank one appears to be working as you can hear it buzzing before you crank it over. Could it be something else apart from the fuel pump?