Lister start o matic

[Three Hummock]

Howdy Folks , can anyone tell me why my lister ST2 takes about 6 clicks or so to start , something does happen each time I press start on the start o magic control panel which I’m guessing is possibly a fuel opening solenoid and once it gets going I notice the ampere meter is in the negative. After running for about 6 hours ( not continuously but maybe 6 runs of an hour in duration) the 2 start batteries need charging. Any suggestions muchly appreciated