F150 won't run

[Bilge Rat]

07 F150TLR 63P L 1065848 J 150hrs.

New filters, plugs, oil
Real gas, newer hoses, primer, fuel tank. 1/3 of the gas is 1 month old, 2/3 is 2 weeks old.

Due to rain the motor has sat for 1 month. I ran it on the hose today.
It ran fine, idle, for 5 minutes i then put it in forward for a min. then rev. then back to neutral. After a min. at idle it sputtered and died.
It would not run when i spun it over. It would only sputter.

Firm bulb, fuel in clear filter, good water flow at tell tale, no warnings on the standard Yam tach.

I let it sit for an hour then squeezed the bulb 1 time then cranked it. It took a little longer than normal to catch and run. It idled for about 1 min. then died again. Spun it twice more and no run.

My fuel pressure gauge has disappeared so that check was out.

The 2 lift pumps are cam driven, can they be checked by pulling the 2 mounting bolts and squeezing bulb?

It is getting late and i am looking at what to check.
The snap-on truck comes by next door tomorrow so i will have a fuel pressure gauge then.

One thing i did before i started the motor the first time i drained 1oz. of fuel from VST to check for water i have done this before with no issues.

Acts like a fuel supply problem but the bulb is full, clear filter is almost full like normal.
Is checking rail pressure and lift pumps for leaks the logical next step or what am i missing
thanks

[Bilge Rat]

Problem solved

Picked up a fuel pressure gauge.
Hooked it up and started motor.
30lbs. on rail ran at 1000rpm. in gear and after 3min. pressure started to drop.
Squeezed the bulb and pressure returned for a short while then dropped again.
Squeezed bulb again and regained 30lbs. on gauge but the bulb remained flat.
After 1 min i shut down the motor and bulb remained flat.

Picked up a good OMC brand anti siphon valve, it worksmuch smoother and with much less vacuum. When i cut the fuel hose at the tank no fuel ran out.

Bulb now springs right back.
Started motor, 34lbs. fuel pressure, motor sounded right and the clear filter fuel level was higher and stayed there.
Pressure is higher and steady thru 15 minutes of running and after shutting off motor the pressure did not drop at all till i removed the gauge about 5 min. later.

Having the right tools and being able to find them easily really narrows down the search for the offending part.
Reading the posts here does help by hearing the troubleshooting methods that are used on the newer outboards. They are a little different than carbed small blocks, direct injected diesel tractors, and 30yr. old 2 strokes.
Suck, squeeze, and fart are the same it is just happening on a boat .