Slightly harder to start after truck in shop

[Dalalen]

I have owned a 6.0 for about a year now and had took it in for some injector problems. Ford replaced injectors 1, 3, and 5 first time in shop and I took it back again and then they replaced 6 and 7 injectors. After they had replaced 6 and 7 injectors I have noticed and made ford aware that the truck is harder to start. They told me I needed to drive the truck hard to get all the air out of the fuel lines (I think this is a load of BS since the first time didn't have any problems starting the truck after 1,3 and 5 was replaced). And now we are 30 days after work has been done and still harder to start before I used to just bump the key after glowplugs are warm and it started. Any ideas on what could be wrong or maybe ford messed up?

Truck Info
2005 F350 6.0 102k miles
Last oil change 100507 AMSOIL
fuel filter and water separator 100507 miles
Batteries less then 6 months old

[Banshee365]

You do need to do some WOT runs to get any air out of the high pressure oil system as the oil rail had to be removed to do injector work. In your case, the longer starts are most likely caused by how fast the oil pressure can build up. If there is any air it will take longer. And, if the o rings around the standpipes are poor there could also be some leakage there. I would just do some hard runs after it's well warmed up and give it a little time. Also, make sure you have very healthy batteries.

[Dalalen]

ok I will try some more hard runs I just came back from pulling my travel trailer not sure if that is hard enough or not but will try more runs. But just thinking here if it turns out to be leaking standpipes whats the best way to tell if they are bad? Will I have to pull the oil rail? I put a load test on the batteries they check out.

PS very new to diesel's I'm still learning how to work on them.

[Evil Eye]

30 days should be MORE than adequate. Within 100-200 miles, you should have ALL the air bled out. Sounds like you are correct about a high pressure oil leak probably the standpipes or dummy plugs like you suspect OR it could be the STC fitting if it is still the original.