Leaky Injectors
ANSWERS
Sorry to leave you guys hanging!
Question: What is a Crows Foot?
Answer: See here
Question: Leakage of lines to injectors or around fittings going into the cylinder head will cause fuel to go into the oil.
Answer: No. Cummins cylinder head is designed so that leakage anywhere going to the injector will drain back to the fuel return system. It is rare for Cummins to have fuel contamination in the oil, anthough not unheard of.
Question: Fuel line nuts tighten to 89 in/lbs.
Answer: Those are the fuel line hold-down brackets, while it's good to make sure those are tight it's not what's being discussed.
Question: Should you remove the valve cover and check the torque of the injector hold-down bolts?
Answer: Shouldn't be necessary, I have never heard of them loosening up. Besides, to get to half of the bolts requires removal of the exhaust rocker arms
Question: Is the valve cover gasket resuable?
Answer: Yup! Several times over
Question: The oily-looking buildup around the injectors is oil leakage from the valve cover, not diesel fuel
Answer: Yes and no. Quite a few guys have had diesel-fuel mostening around the injector line fittings at the cylinder head causing soily dirt buildup. On the HPCR system due to the constant high pressure it's understandable to have very slight leakage of diesel fuel here, not really anything to lose sleep over. These are the nuts in question that should be checked for proper torque, and have been found to be loose on quite a few trucks.
So to conclude. . . check the torque of your fuel line nuts at the cylinder head, using a torque wrench with a crow's foot. You may have to remove your air horn to get to cylinders 2 & 3. But at least you can correct the problem that is being discussed in this thread without removing the valve cover!
Any more questions? Be glad to try and answer them
Question: What is a Crows Foot?
Answer: See here

Question: Leakage of lines to injectors or around fittings going into the cylinder head will cause fuel to go into the oil.
Answer: No. Cummins cylinder head is designed so that leakage anywhere going to the injector will drain back to the fuel return system. It is rare for Cummins to have fuel contamination in the oil, anthough not unheard of.
Question: Fuel line nuts tighten to 89 in/lbs.
Answer: Those are the fuel line hold-down brackets, while it's good to make sure those are tight it's not what's being discussed.
Question: Should you remove the valve cover and check the torque of the injector hold-down bolts?
Answer: Shouldn't be necessary, I have never heard of them loosening up. Besides, to get to half of the bolts requires removal of the exhaust rocker arms

Question: Is the valve cover gasket resuable?
Answer: Yup! Several times over

Question: The oily-looking buildup around the injectors is oil leakage from the valve cover, not diesel fuel
Answer: Yes and no. Quite a few guys have had diesel-fuel mostening around the injector line fittings at the cylinder head causing soily dirt buildup. On the HPCR system due to the constant high pressure it's understandable to have very slight leakage of diesel fuel here, not really anything to lose sleep over. These are the nuts in question that should be checked for proper torque, and have been found to be loose on quite a few trucks.
So to conclude. . . check the torque of your fuel line nuts at the cylinder head, using a torque wrench with a crow's foot. You may have to remove your air horn to get to cylinders 2 & 3. But at least you can correct the problem that is being discussed in this thread without removing the valve cover!
Any more questions? Be glad to try and answer them
Thanks to all, I'm going to check my lines in the morning if they are ok it must be oil. I did have a small amount on the passenger side as well but the main concentration is by the 3 rear injectors on the drivers side. I also have a stain that runs on onto the tranny, not dripping wet just a stain.
If it is oil can the valve cover also be a little loose???? Maybe just a 1/4-1/2 turn to correct the leak???
If it is oil can the valve cover also be a little loose???? Maybe just a 1/4-1/2 turn to correct the leak???
On mine everything is very tight. It's oil, no doubt about it. It's coming from the threaded in female adapters in the side that the fuel lines go into. If it were fuel it couldn't be wet up tight against the side. It's not dripping wet and therefor if it was to go to the dealer there would really be nothing to repair.... after they cleaned it off really good it would take another 10k to surface again! I'd bet this is a common "issue" with the HPCR set-up.
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