Tuff Torq K71 Gearbox Oil Fill Level Problem?

Hi everyone,

I have a British made Countax diesel D18/50 fitted with a hydrostatic Tuff Torq K71 transmission. It also has power steering which runs from the gearbox. I have changed the oil however I haven't put the amount in which is suggested in the manual. It states it should have 4.0 litres of 10w40 oil however I have only managed to put 3 litres in. The oil was overflowing out of the filler cap so I started the engine and got the oil circulating through the power steering. I have rechecked the oil and it has gone down a small amount. There is no oil in the reservoir which sits above the transmission so I am unsure of what to do because surely if I put more oil in the resevoir it will overflow out the lower filler cap? I really don't want to over fill it and blow a seal. Please can someone shed some light on this situation as I have been left scratching my head. Also just for arguments sake I did fully empty the original oil from the unit, it was totally empty before I filled it up with new oil.

Thanks in advance,
George.

Here is the manual I was using http://ift.tt/1OqFtfe