Long cranking before starting 93

[NapaBavarian]

Do IDIs have a fuel system check valve? My ambulance takes 30-45 seconds of cranking before it fires up, hopefully it has an easy fix, once it fires up it runs great, at lweast at idle, transmission to come soon.

 

[Agnem]

Yes and no. If you have a 7.3, there is a little check valve in your fuel filter header that is supposed to prevent drain back if you have leaky return lines. There is also one on the fuel return in the tanks. However, you have leaky return lines. The check valve is only a secondary defense. The primary one is just to keep the fuel system sealed.