I want to change oil and gas on a recently purchased '03 GFI LE RFI. On my '97 GSX this was no problem - siphon tube in, pumped out. On this GFI I'm running into obstruction, my siphon tube won't pass. The diagram in the service manual doesn't show anything that might stop the tube from passing. For this simple chore I didn't want to start disconnecting outflow tubes if I don't need to. Any hints?

Reasons for changing
1) gas is of unknown age/condition
2) oil is also of unknown origin/quality, I will run XP-S