My 89 F250 is having hard starts in cold and warm after sitting a while.
Today I drove it around the block and it stopped , I tried to start it , and after many cranks I put a little starting fluid and it started rough. I suspect air in fuel.
I took the fuel filter out and I found that the fuel only reaches half of the filter. Could it be that the fuel discharges through the fuel pump? Should I change the fuel pump? Thank you all

 

I bypassed the fuel filter with a clear hose, and I saw that the fuel instead of staying, it would go back to the tank through the fuel pump. Might this be why the filter empties and causes a hard start?

 

What kind of pump do you have - stock or? How old is it? Might be worth a new pump or change to electric if you have stock.

 

It have a mechanical pump.

 

I would change the fuel pump. Good luck