OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers SB 45 with Kirby / Lauson engine - How much oil?

Hi RustyVicta, and a warm welcome to the forum.It' great to have another Scott Bonnar Model 45 owner on board.
We all like to learn new things and tinker here.
From what I have found through some research for you, 620 ml is mentioned.
But here on the engine(H4, but I would presume it would be the same for the H30) is the makers instructions:

Fill to overflow or to full mark if it has a dipstick.

Once again RustyVicta, to OutdoorKing.