Is there a write up for 6.7 injector/connector tubes?
 

I am fighting a 6.7 that is making oil very quickly. It is up over an inch in 1000 miles. I am planning to start diagnosing and fixing things, and was looking for some kind of writeup on how to go about checking the injectors and connector tubes. Any help is much appreciated.

Stop driving the truck!

It doesn't take much fuel in the oil to ruin the motor!

Any injector installation guide should be able to help you out. Not sure if you are looking for instructions on how to diagnose, or how to install/remove though.

Link to installation of injectors is here.

I don't have an option on the next 60 miles to get it in the garage. After that, yes it will be parked until it is fixed and the oil changed.

Thank you for the link to that guide, I know it will help when tearing into the motor.

I am also looking for a way to diagnosis the issues. As in, what to check first, and what specifically to look for. It is making a large amount of oil, has relatively high egt when cruising the highway unloaded (750 + on the highest mini maxx setting), and I just got a phone call that it threw the CEL and lightning bolt. I believe it was/is in limp mode right now, as the driver says he is only getting 2 psi of boost. I am going to have the driver pull the codes prior to returning to the garage.

Call Rich at Glacier Diesel, thats where I got the link from. Hes a straight shooter and can guide you in the right direction Im sure.


Getting some codes would help too.

I think I found enough to go on.

That pic, along with the torque specs from the guide, should be enough to check what I need. Thanks.

Is the CP3 a possible culprit?
 

I spent most of the weekend digging, fighting, cursing, and bleeding in the engine bay of the 2008. I am a large guy, and whoever decided to put that steel shroud behind the no 6 connector tube is just mean. I found nothing so far, except a very wet CP3. There are no external cracks on any components. The only thing near/connected to the fuel rail I saw that looked wrong was the #4 fuel line. It has a seriously stepped ring around where the nipple seats into the rail and looks like it was over torqued. Since the truck was running very smooth prior to dis-assembly, and was still making oil, is there any opportunity that the fuel dilution is happening within the CP3 pump?

Is this a reasonable way to test the CP3?
 

I am still working, and am trying to test the CP3 for bypassing before spending serious money for testing. I have a fuel can rigged up, and removed one of the banjo connections that go between the CP3 and fuel filter. I have the tank on a ladder for gravity feeding, and connected a test line to the pump. I put an empty pan under the oil drain after removing my contaminated/diluted oil. Is it at all reasonable that a bypassing seal would let fuel leak down through the motor and into my catch pan? Does it matter which connection I hook the test can to for checking this? I am planning to pressurize the tank if I don't get any results gravity feeding the pump.

Unhappy resolution.
 

Good news: We had all the injectors tested, and they came back fine. I have re-assembled the truck, and it starts and runs fine, with no obvious leaks.

Bad news :We took an oil sample (from before work began) after the injectors came back clean and it came back perfect. I never needed to go through all that work.

Our only guess now is that the mechanic (not me, thankfully) that changed the oil right before this adventure began overfilled it. [verymad] I trust him for the most part, so I am wondering if there is a certain way to fill these things correctly. Are you supposed to wait a bit to check them as you add the last few quarts?

Thanks for the support all. I hope this helps somebody else down the line. Have the oil checked BEFORE opening the motor. [redface]