1986 Ford f250 every time I turn off the truck for a few minutes and then try to start it ,it floods could this be a fuel relay issue.
Do you still hear the fuel pump running after you turn the key off? if you do then yes it could cause a flooding problem, but with the age of the rig I am leaning towards leaking fuel injectors, you could find out by running a fuel pump pressure tests and see how long it hold pressure after turned off, if it bleeds off really fast, block off the fuel return line and retest, if it still drops and won't quit falling then you have some leaking injectors.
Search Ford F-250 Super Duty Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Ford F-250 Super Duty Experts