starting problem td 42 please help

[banksy]

Starting problem on td 42 only first start or if been sitting for a day rebuilt motor and 13mm plunger on pump have put new fuel lines on manual switch for glow plugs and new glow plugs as well new fuel filter assembly I'm out of ideas

[K1W1]

Could you possibly elaborate on what exactly the thing does when you are having trouble trying to get it going?

[Patrolling Paddy]

Is it coughing and carrying on like air in the lines?
Are the injectors leaking down?
Is it leaking at the filter? This could allow air in.
Are the glow plugs all working correctly?
Has it run properly since engine rebuild? Are all cylinders showing good compression?
Is the governor in the pump working properly?

Bit hard to help with the lack of symptoms explained sorry.