[mmonsterbuck]

imported post

carbs worked on, started it overflowed by rear tire, hour later, hydrolocked, took plugs out, cranked motor by hand out came gas, got it started, gas out overflow again, shut off, started again rode it home with gas cap loose, started it a while later it was fine, could gas cap be pluged causeing pressure, forseing gas by floats, heard whine noise comming from gas cap till i relieved pressure when i rode it yesterday

 

[DaveO430]

imported post

Gasoline will only build up a small amount of pressure, called vapor pressure, don't recall for sure but only a couple of PSI. Not any more than the fuel pump would I don't think. There is probably a problem with one or both of the needle valves or the float levels.