Made up this simple fuel transfer device years ago, has taken the pain out of holding a full jerry while waiting it to drain into fuel tank. Have fitted petrol safe hoses since these photos were taken so I can fill the Honda 3.0 on the back of the ute.
With this I can place jerry on the ground or leave it in the back of the ute.
Taking care not to over pressure the jerry, walk away and do something else while the transfer is happening. Come back from time to time to top up pressure with Air compressor connected to valve on device.
Jerry cans as we all know are notorious for collecting scale etc contaminating fuel, the filter of the device collects any particles.