Hard start after lift pump replacement

Lift pump started leaking the other day so I replaced it with a Carter assuming they all suck now but thats the best of the worst. Bled all the injector lines I could reach easily all at once till they wept diesel. (this is a factory turbo so two lines weren't accessible) retightened lines and truck started right away. 2 days later and I'm experiencing hard starts when cold. First crank, it starts for one revolution then dies. Assuming its using the fuel between lift pump and HP pump. Then it requires 30 seconds of cranking till it starts. Does this sound like the line from tank to lift pump is empty? Like the Carter I bought has bad check valve? Do lift pumps have flow back prevention? I've been reading the whole forum and feel like someone who has a mild cough, reads the internet, and is now convinced they have ebola. Like, this could be air intrusion too I guess. I do wonder why yall diagnose that for hard starts but normal running when warm. Does air intrusion not matter as much when warm?

It certainly sounds like air intrusion. The affect of that and drain back are about the same--feeding air to the injectors. Try pulling your fuel filter. If it is not full start hunting for answers. Examine each and every joint you touched while replacing the lift pump. Also, charge your batteries overnight. A less than optimal battery won't spin the starter fast enough.

Speaking of the starter, don't crank it more than 15-20 seconds at a time. Let it cool between crankings. Its working hard, fighting high compression. If you crank too long it will overheat, and before long you'll be buying a new starter. So, crank 15 seconds and let it cool 2 minutes.

Thinking about it, when you replaced the lift pump you removed any check valve along with the lift pump. There may have been a significant drain back at that time. In that case keep cranking and you'll get it. Be sure the fuel filter is full.

Okay you rock. I wonder if air is getting in at what appears to be a fuel filter housing leak. I didnt mess with this but its clearly leaking in any case.

EDIT: Yes I will address this first

It does appear to be leaking. It may be the cause of your issues. Remember that air intrusion only happens when the engine is running. If it runs fine and doesn't act up, it's not air intrusion. It's only fuel drain back. Since you didn't mess with anything besides the lift pump (assuming here), if fixing the leak at the fuel heater on top of your filter head doesn't fix the problem, then you can narrow it down to the lift pump area. The rubber fuel line that goes from the frame to the lift pump may be bad. It can gave slight cracks in it which may cause air to come in and let the fuel drain back to your tank. It should give you air intrusion too though. If that's ok, then I'd suspect the lift pump, new or not.

IDIBRONCO said:

It does appear to be leaking. It may be the cause of your issues. Remember that air intrusion only happens when the engine is running. If it runs fine and doesn't act up, it's not air intrusion. It's only fuel drain back. Since you didn't mess with anything besides the lift pump (assuming here), if fixing the leak at the fuel heater on top of your filter head doesn't fix the problem, then you can narrow it down to the lift pump area. The rubber fuel line that goes from the frame to the lift pump may be bad. It can gave slight cracks in it which may cause air to come in and let the fuel drain back to your tank. It should give you air intrusion too though. If that's ok, then I'd suspect the lift pump, new or not.

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OH MY GOD I THINK I FORGOT TO TIGHTEN THAT HOSE CLAMP!!!!! ITS JUST SLIPPED ON PAST THE HUMP!!!!! HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAH

Edit again: I just didnt remember tightening it but it is tight. Orings are on the way. If heater stops leaking, and hard start persists, I'll replace low pressure rubber hose and clamps with better ones. Heater wire plastic connector might be cracked we'll see. Will NPT plug it if so.