4BT3.9 Cummins Hexagon Flange Head Cap Screw 3920779 Parts Catalog Ref No. Part Name Part No. Required 　 Cylinder Head 3910276 1 1 Cylinder Head 3913391 1 2 Expansion Plug 3812092 5 3 Pipe Plug 3906619 2 4 Pipe Plug 3008468 5 　 Intake Valve 3802005 6 5 Valve Collet 3900250 12 9 Hexagon Flange Head Cap Screw 3920779 6 …