got it all working. there is no manual in the package. the system works on vacuum. so when the engine stalls the gas will no longer flow. that was not clear to me before. I don't use petrol at all so I start with a drop of alcohol on the filter. you can push a button to let gas flow manually but for me that didn't work. notice that I use it for charging batteries, so no fluctuating load. but it's nice and cheap.