the diesel should not return back to the tank overnight.if it is you need to find out why.i have had a few ford 1.8 diesel engines with this fault come to me and is usally a crack in a fuel line or once it was a seal on a fuel filter,if you have changed the fuel filter i would look there,if you squeeze the priming bulb is it hard or soft? if it is soft and priming you have an air leak allowing fuel to return to the tank,hope this helps
mike
February 2009
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