stalls on cold start...what gives ?

[Northern Wrangler 6.2]

New problem....first time the old girl has even hiccupped in 50,000 miles...

In the morning or after sitting all day (at work)...I start her up...lights up right away, as always, but then feels like it runs out of fuel....pedal non-responsive, engine surges, then dies......restart..(lots of cranking)....and it lights up again..then seems fine. When engine is warm, no issue, runs and pulls as always, fuel mileage good, oil consumption is unchanges, everything sounds the same.....started a couple hundred miles after fuel filter chenge. I added some conditioner to the fuel, drained the water from the seperator (none present)....

Am I sucking air from someplace ?.....lift pump weak, injector pump weak ?....am I losing prime after sitting ?....

Any help will be greatly appreciated.....long trip with camper and trailer full of junk for the swap meet next weekend.....don't want (embarrassed) to take my gasser....HELP !!!
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[ZZ]

I hate to say it, but it sounds like you are having the fuel leak down problem after she sits for awhile. Does it start and run a few seconds and then die, and then do you have to crank & crank to get the prime back?

My truck has done this twice in the last three years. A new fuel filter fixed it the first time. The 2nd time was a loose hose clamp on the pet cock valve by the thermostat housing.

[Robyn]

When was the last time you replaced the mechanical lift pump?
These little beasties have a bad habit of the check valve going south which results in fuel drain back. Just to run an expieriment try parking the critter with a fair amount of fuel in the tank and get it nose down some. This does not need to be precipitous but just a good down angle and then see if this happens.
If she starts and runs fine then replace the fuel pump and you should be fine.
If you have loose hoses above the pump they will leak fuel and if they are leaking below the pump it will suck air and run crappy even when warm.
Give it a shot
Robyn