Bongo Fury

as title, it's a right pig when its hot but left overnight, it'll start before i let go of the key.
only started doing it recently, been perfick up to now, any suggestions as to what it might be?. was serviced last week

i can only think of a few possibles at the moment, assuming it's diesel

the fuel pump seals ( most likely the one at the back of the pump ) i have had the same problem as you describe and this was the fault
fuel filler cap causing a vacuum
blocked banjo filter

If it was serviced last week I'd have a chat with the garage that serviced it. Maybe they did something or can suggest something that may be causing it.