6.9L IP on a 7.3L?

adamsanders

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OLDBULL8, the first pump did run well but would not start after it was hot. Seeing as how this seems to be a top symptom of needing a new IP, I went and bought a cheap pump of craiglist as a gamble. When I installed this one, the truck ran very rough and had no power. I wanted to advance timing just to see. I put a rag lightly in the glowplug hole and when I rotated the engine one rotation blew the rag out and the other did not. So I know I was at TDC in compression. I then rotated the gear one tooth but it helped the pump none.
 

OLDBULL8

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OLDBULL8, the first pump did run well but would not start after it was hot. Seeing as how this seems to be a top symptom of needing a new IP, I went and bought a cheap pump of craiglist as a gamble. When I installed this one, the truck ran very rough and had no power. I wanted to advance timing just to see. I put a rag lightly in the glowplug hole and when I rotated the engine one rotation blew the rag out and the other did not. So I know I was at TDC in compression. I then rotated the gear one tooth but it helped the pump none.

Well, that's a lot more info. But I'd still make sure then that you don't have air intrusion. That filter to IP line will suck in air at the IP and still not leak fuel.
 
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adamsanders

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Well, that's a lot more info. But I'd still make sure then that you don't have air intrusion. That filter to IP line will suck in air at the IP and still not leak fuel.


Ok how can I check for this? I'll look at it tomorrow but if it still turns up nothing I'll order a moose pump and be done with it (hopefully). Would air intrusion make it fell like it has no power? It idles great but actually driving it is a disaster.
 

adamsanders

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The more I think about this the more I want to just replace these fuel olives. If my local diesel shop ha some Ill grab some tomorrow. The reason being the more I think about trying to drive the truck with that IP the more I think it was surging and not missing. It idles great but as soon as the engine is under load it starts acting up. I guess some air intrusions may worsen when the pump is pulling more fuel? Idk, it's a last chance thing and wouldn't be a bad idea to replace before the new pump anyways.
 

Macrobb

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Try using some clear line after the lift pump, to check if you are getting air into the filter(and from there into the IP). That's what it sounds like.
 

adamsanders

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Thanks for your help. I believe my problem is probably air but I think it is something to do with the pump itself. It is leaking fuel pretty steadily into the valley so I would assume if fuel gets out air can get in. I called Mel this morning and ordered a Moose Jr. IP so hopefully that will solve my issues. I will put the gear timing back to the correct position before I put the new IP on. Hopefully I can like it back up correctly. I'm pretty sure I can though.
 

IDIBRONCO

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If you're still n/a, I'd highly recommend turning the fuel back. I only have about 2/3 or so throttle before it starts rolling smoke. I've turned mine back, too.
 
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