Problems with power loss on MF 6180

[Pat Vesey]

I have a 1996 MF 6180. Lately, the tractor began to lose power. You could drive for an hour, but when you idle for 2 minutes and start off again, it loses power, starts to smoke a little ( as if it was not getting fuel correctly ). Now it has got worse, driving along and then loses power. When you switch off for a night and turn on in morning its ok for a while and starts playing up again. Has anyone any answers to this problem. It has a Standyne fuel pump.