When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
1991 f250 starts and runs fine turn it off wait 30 minutes it starts runs about 30 secounds rough then shuts off wont start wait several hrs and it will start and run great
does it fire up ok when the motor is cold, then not start when hot?
if so, i am gona say your injection pump is shot. the alumium pump expands when hot, throwing the tolorances out the door and causing the hard start/no run issue.
it doesny real matter yesterday ran for about 4 hrs shut off for maybe 10 min.started fine waites about an hour started fine about 1/2 hr later started ran rough and shut off about 2 hrs later started fine
has the selector valve ever ben touched? sometimes they go bad and can get stuck between tanks and sucks air. but that is a long shot. i have no clue, that last one is a major guess.
Check the hard fuel line running under the motor along the cross member, they can rub through sometimes. The fuel pump also has a weep hole that will leak if your diaphragm tears.