Another weird fuel return issue

[Diaric]

there shouldn't be any resistance, it should free flow. down under the alternator the steel line connects to a hose that goes to frame, blow from there. if its got resistance, the return will pressure up and stall the engine or blow off return lines like you did. if your blowing from rubber connection at IP, its tied into the injector returns.

what year is the truck? my description is for the square bodies, the lines were routed different on the next generation

[smackzed]

Whether the return is plugged past the injectors is important, but the fact that non of his injector returns spurt fuel is more important I think

[Diaric]

Originally Posted by smackzed

Whether the return is plugged past the injectors is important, but the fact that non of his injector returns spurt fuel is more important I think

first post is about stumbling with return hooked up and blowing off cap. that is answered by plugged return line. I'd ignore no fuel on one side's return till thats solved. the fact it runs means injectors get fuel, cracking is unnecessary

[Jace]

Yes it's getting fuel to the injectors or it wouldn't idle as smooth as it would. I did notice that when I blew air into the rubber hose off the injection pump that the injector return hoses filled with air,so I'm guessing that what I did was a waste of time. I'll try blowing air at the steel line next.

[smackzed]

The injectors need return fuel to lubricate. If it's run with no return fuel for any length of time you can say bye bye to the injectors. losing 4 brand new injectors is no fun

[Jace]

i wont drive it this way. I just cant think of reason why fuel is not coming out of the returns on the injectors. Maybe the injectors are not getting enough fuel to them to even have return fuel?

[Diaric]

have checked if they return fuel rev'ed up?

if it idles smooth I'd figure it must be getting proper fuel

[smackzed]

Originally Posted by Jace

i wont drive it this way. I just cant think of reason why fuel is not coming out of the returns on the injectors. Maybe the injectors are not getting enough fuel to them to even have return fuel?

That's what I'm thinking. Have you tried opening the air bleed with the truck idling? If it starts to run poorly with the air bleed open, you have a fuel supply problem...pre IP.

I'm still interested in what happens when you crack the inj lines. Doesn't take long and it may have an unexpected effect

I think Diaric is right tho and you should also see if they start returning fuel with some throttle.

[Jace]

The air bleed on the filter? If so, I changed that all out to a spin on fuel filter.

[Jace]

When I crack the lines, fuel weeps out and the truck idles real rough