316 Fuel Pickup

I replaced all the fuel lines on my JD316 earlier this year. The tractor runs out of gas with 1/4 tank still showing on the gauge. I used about 4-5" of fuel line inside the tank and installed a new pickup screen and check valve. I pulled the tank and pickup hose today and the hose has a 90deg bend in it. There are no kinks,it's a smooth gradual bend. I thought the hose would be laying on the bottom of the tank,but it can't be since the tractor runs out of fuel at 1/4 tank. JD parts does not specify a length, it just says cut from a 10' piece of M62370. Does anyone know how long the hose in the tank should be?