Bosch Idle Problems with smoke

[Dan!]

Squeeze the hand primer until it goes hard (with the engine off) and then keep trying to squeeze it and you should be able to see/hear where its leaking from. You literally only have to look from the pipe going out of the hand primer to the fuel filter housing, then the housing itself, then the pipe from the housing to the pump, and then the pump itself. If you really cannot see any leaks anywhere it would suggest your hand primer is knackered and the one way valve is letting fuel drain back to the tank. Although id say this is unlikely if it was running fine on the lucas.