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Discussion Starter · #1 ·
Title says it all. I recently had a cp3 fail and got that replaced with a local shop that does a lot of these trucks. After I got it back it shortly started chiming about low oil pressure. I called the shop and they thought when my old pump failed it could have dumped fuel in the oil so I changed the oil Friday night. I got 3.5 gallons of "oil" out of the truck. Replaced it with 2.5 gallons of oil. That fixed my pressure problem. I used the truck Saturday to haul a 25' flatbed and bring home an empty 1500 gallon water tank to fill for a nurse tank for a sprayer and didn't use it at all Sunday. This morning I pulled the stick and I can already smell fuel in the oil and it's already showing over full.

After I got my truck back from the shop my injector balance rates were looking better than ever. +/-2 tops. When the cp3 was weak it was closer to 3.5 on a couple of them. I used a brand new cp3 from LDS. The pump is the only new part in the system but it's new. I am also dealing with a possible cracked fuel rail but I don't think that leak would have any way into the crank case.

Any advice on where to start looking for my trouble? I know most often this is a sign of injector failure but since it started with the new cp3 I am looking for opinions. Do the experts think I have several issues or do these point toward something I can't see?
 

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Probably, most likely an injector/cup or cracked return line or banjo bolt. The only way to really tell. Pull the upper valve covers Run it and watch where the spray is.
 

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Discussion Starter · #3 ·
Balance Rates taken today at operating temp in park
1087118

Balance Rates in Drive
1087117
 

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Discussion Starter · #4 ·
50 miles is all I got before the alarms were ringing again about low oil pressure :(

If my new CP3 was leaking, could I see that through the oil fill tube? What I mean is could I take out the fill tube and turn on my lift pump and be able to see fuel there or maybe even run it and see in there enough to rule it out or know it was the new part?

The mechanic that did my CP3 took on an engine change job after me and has no idea when he could get to my issue. It's looking like I will be on my own or paying the dealership rate to figure this one out.
 

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Discussion Starter · #5 ·
Does anyone know how to safely run an lb7 with the valve cover off? I’ve started dismantling the passenger side to get down to the valve cover and I’m struggling to figure out how I can keep the Ficm and be able to see behind it. I haven’t even thought about the drivers side yet. What do I need to have connected or what do you have to put back on after you’ve got the cover off for it to run?
 

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Put the lowers on connect the plugs and FICM of course and fuel head and run it for a short time as you know! Of course that is just if the return lines are in place and everything inside is intact.
 

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Discussion Starter · #7 ·
I think I found my problem but I’m not positive. I’m planning to continue my search. At any rate, take a look at these pictures.

1087416

1087417

1087418

1087419

I’ve been dealing with what I think is a cracked fuel rail that happens to be directly over this gasket mishap. I hope this is the source of my issues but I’m still digging.
 
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