its an 1987 f250 6.9 liter truck,

well the water in fuel light was on, i drainded the water form the fuel/water seprator. go to start the truck, it ran for 15 secs then died and i havent been able to start since. I replaced the fuel filter, it seems to run when i top the fuel filter up, then dies a few secs later(after the fuel is burned form the filter)

it seems to not be getting fuel up into the filter as it is empty when i remove it.

what can the problem be? ip pump?fuel pump? could my o-rings be shot? fuel return line? i am very new to this truck so all and any help would be great.

 

I believe on your year of truck air being sucked back up the drain hose on the seperator can be a problem, valve doesnt seal well enough. Try plugging and clamping that hose, see what happens. LOL Welcome to the forum, you will get lots of good advice on here, so stay tuned, I'm sure others will be along to confirm what I've mentioned and more!

 

chopperdaw,
Welcome to FTE and the IDI diesel forum.

Sounds like the lift pump may have died.
Have someone crank the engine while depressing the schrader valve on the fuel filter.

Caution, don't crank the engien for over 20 seconds without a 2 minute rest/cooling period.
The starters are heat sensitive and rather expensive.

If you have a pressure gauge, the lift pump pressure should be about 5 PSI measured at the filter header.
If you remove the schrader valve and catch the fuel in a container, the lift pump should deliver 1/3 pint of fuel in 10 seconds of cranking the engine.

Post back with your findings.

 

ok which hose do i plug? it seems as if no fuel is being delivered up to the filter, by lift pump do you mean the mechanical fuel pump located on the front left(looking at the engine) i am trying to narrow the problem down without having to replace every single component in the fuel deilevery system. all and any help is awsome.

if i depress the shcedler valve off the filter assembly while cranking the engine over will this relvieve any air that might be trapped in the fuel lines? and to check the pressure can i use a tire guage?

 

The lift pump is the mechanical fuel pump located on the lower passenger side front of the engine.

If you depress the schrader valve, it will let the air pressure out of the filter and fuel should pump out once the air is replace with fuel.

A tire pressure guage is not going to be accurate at pressure that low, a fuel pressure/vacuum gauge would be better.

As I was typing this I happened to think, how much fuel is in the tank?
The fuel pickup tubes are famous for breaking off which causes the engine to run out of fuel around 1/4 tank or so.

 

the frotn tank is full the rear is 1/4 full i have it switched to the fornt, i will go and test for the amount of fuel which is comming out of the vavle, if there isnt anough fuel comming out should i replace the lift pump? i will also be replacing all the o-rings and fuel line on the truck as it is 20 years old