there was 40L in which means aprox 1/2 tank. I filled about 10 l on the tank to be sure but it still didnt start until I used start gas... and voila.. it runs.

the problem is I'm not sure why it runs now.. as I've attempted all of this before. Dont trust the car now and drive around with a spare tank of gas just in case it has to do with transfer pump.

Will update after I've used it a few days.