Warm start issue with a difference

This is a complete drop in from Jasper which included the fuel system. The fuel system is out of warranty. Only has 9000 miles on it. Has two new batteries and a new set of Beru (Manual) GP's

Engine starts great from cold but after trying to restart it on a warm engine it starts and stumbles and stalls. Just like air intrusion symptoms except that it would do the same from a cold start if it was air in fuel.
Tried the cool water trick on the IP and it started and stumbled for a bit until it smoothed out. It certainly seems like its the IP but after only 9k it seems unlikely.

Cranking is real fast so I know there's nothing wrong with the starter. In the morning in the high 20f it spins and starts in less than 2 seconds.
Thoughts?

I wouldn't be surprised. Seems that there are MANY poor quality rebuild IP's out there. And with todays ULSD; they just don't last. Seems like even a well built DB-2 pump dont last more then 200,000miles

Well another winter arrives and the same problem has resurrected itself. Weird, cause I went all summer and fall with no problem, but as soon as the ambient temps drop to the mid 20f its back.
Went to work this morning at 06:30, arrived at the job at 7am. Left the truck for two hours, came back, started up, coughed and died. Took three 30 second bursts to get it started again. Drove two miles and stopped to pick up the weekly doughnut order. Came back, started and stumbled. Had to feather it a little to keep it running. What could this be? It can't be air intrusion because it will start right up from stone cold. Acts like air intrusion though! Weird!

Yes its air leaking in but no fuel leaking out. Heres the fuel issue explained very well by Mel. Stick a straw into a bottle of soda, beer or any liquid you like to drink. Put your thumb over the end and lift it out of said fluid. nothing drops out. Not let in some air by slipping your thumb off just a bit from the top of the straw. It runs out fast. Our fuel systems are built this way. Allow any air to suction in and you loose the fuel prime in the injection pump. finding where this air is suction in and no fuel is pumping out is tuff. Please try this. Tighten up one end of the filter to injection pump feed line. Those brass line nuts have a seal washer called an olive in them. The harden over time and will suck air before leaking fuel because air moliques are smaller than fuel moliques. Only tighten one at a time til you find the problem. The lift pump to filter head has a brass nut with an olive in that end too. That one is a 3/8 where the line feeding the injection pump is 5/16. They are easy to find at any good injection pump repair shop or typ4 or Mel will sell you them too. They are very tuff to remove when they are hard so soak in brake fluid overnite and use a dental pick to dig them out. Make sure the olive is set back from the line slight flair so the line sets well inside the female fitting ends for support.

My IDI couldn't maintain fuel pressure for anything when the temps dropped below freezing. I had a gauge in the cab, and anytime it was below freezing it would be around 1 psi or lower (often zero). I know the fuel wasn't gelled, as I ran additive in it and the Jetta TDI never had any trouble running at much colder temps. Filters were clean. Tried 3 different mechanical fuel pumps, a Delphi, and two Carter's, same deal. Mine however ran great, but the gauge bugged me. Warmer temps and I'd have 3-4 psi. Maybe a similar issue for you.

A long shot, but do you have the old water seperator on the firewall below the brake master cylinder ? It has been the cause of a lot of problems and most owners have either blocked off the drain line (insert bolt and then clamp) or remove the whole selerator.

swap out the lift pump and grab a e-pump from Doug here in the group buy thread.say goodbye to the most common idi issue for good.truck wont do that start stall mess at all.just fix fuel leaks as they pop up.
i'll never run an idi engine with a mechanical fuel pump.simply not worth the hassles.

The posting about changing to an electric lift pump is one of the best modifications for our idi rigs. Doug has the best deal on this pumps too. They run forever. Question that ... Well next time you see a semi trailer running a chiller frig up front at the top think about how long they run going across this wide country keeping something frozen or chilled. They simply don't break down and they suct diesel fuel from under that trailers back by the spare tire rack. Those pumps actually suck fuel better than pushing fuel like all the other electric pumps.

Truck wouldn't start this morning, definitely air intrusion because it wasn't even coughing. This truck came with dual fuel filters. I deleted the front filter because that one was half empty and the other one was full when I checked them. Bled it and got it started.Took for a hard drive to get juice back into the batteries and let it sit for a couple hours. Started right up just now so I think the front filter housing may have been the culprit. We will see though in the morning.

I ordered a Facet Duralift 40285 because the PSI is closer to the stock psi for our trucks. I think the group buy pump is probably better for turbocharged IDI's. I run an NA IDI so I don't want my IP being ovefuelled.
Thanks for the helpful replies

The pump this forum recommends will feed both a turbo or na engine with no problems about overfueling. Thats a gasser problem but thanks for bring it up just the same.

One advantage to all this is that I already have a nice solid bracket for the new pump to bolt onto thanks to the front filter delete!

Just went out and started it up again after another three hours of sitting. looks like the problems solved;p

I may install the Facet pump as an auxiliary priming pump on a toggle switch until spring rolls around again and I can comfortably lay on the ground for the mechanical lift pump delete.

Does anyone think the facet pump could be damaged from having fuel pushed through it from the stock lift pump? I won't be using both pumps together but the facet pump will be in front of the lift pump and only used for priming if the need rises. I don't want to take the risk of damaging it by forcing fuel through it.

Yes. Pretty sure some people had problems when they mounted them down low and fuel was pushed threw.

Do NOT run both pumps.
If you're gonna use the electric, then USE it.

You don't technically have to remove the mechanical pump to take it out of service. At least not right now.

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79jasper said:

Yes. Pretty sure some people had problems when they mounted them down low and fuel was pushed threw.

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My pump will be mounted in the engine bay right next to the fuel filter. Any substantive record of any damage?

Do NOT run both pumps.

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Wasn't planning on it. Like I said. I only intend to use the E pump as a primer until I can comfortably lay on the ground and mess with the mech pump.

If you're gonna use the electric, then USE it.

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see reply above

You don't technically have to remove the mechanical pump to take it out of service. At least not right now.

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So the mech pump can run dry without risk of rupture?

IMHO, the pump wasn't your problem, why mess with it?

fuzzy1626 said:

IMHO, the pump wasn't your problem, why mess with it?

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Your right. Air intrusion was the problem which is quite common with these engines. I was fortunate that I was able to track it down but sometimes that just doesn't happen. I exhausted my batteries twice yesterday trying to get air out of the system to say nothing of the excessive strain I put on my new starter motor. I probably took a few hours of it's life from cranking.

It was also in the low 20s F here in Indy so it was not a pleasant experience messing with a fuel injection system when my warm living room was only 30' away. I don't mind sitting in a hide in such temps waiting for an unsuspecting Coyote to pass by but messing with cold metal isnot my idea of a good day out.

An electric pump eliminates the need for excessive cranking when the issue raises its inevitable ugly head (and it ALWAYS does eventually with these engines). It will also save on batteries, starter and my need for a more sanctified use of the tongue when dealing with frustrating situations.

Furthermore, I noticed that you have lots of little extras on your truck. I want my little extras too