LB7: Diesel in the oil, injectors ok.

[Jdeharo]

I have a 01 duramax, 118000 miles, it is mainly used for pulling a 30 FT toy hauler trailer, on our last trip it died on us, and would not start anymore, and after looking around I noticed a lot of oil and diesel smell all over the underside of the truck, the truck was towed to a nearby Chevy dealership, I was told I had a leaky injector and it would be 5K to replace all 8, at that point I decided to do work myself, I checked the balance and they are within limits, only number 8 spikes above 4 on and off, the scanner show no codes at all, I removed the valve covers and got the truck running added a dye and injectors cleaner off the fuel and return lines, I don not see any injection leaks at all, no dye anywhere.
Is it possible that the injectors only leak under load?
Could the diesel be coming from somewhere else?

 

[mike diesel]

You need to ramp up rail pressure while looking for leaks. They probably do not leak at Iidle, which is around 5000psi of rail pressure. Unplug the FPR briefly and check for leaks. That will spike rail pressure to 23000+ psi. Wear safety glasses or fuel may spray you.

 

[malibu795]

Return line seals could do that as well

 

[Stingpuller]

Injectors

You need injectors. Balance rates mean very little. Lines don't come lose or start leaking after 100k miles. It sucks but it's time.

 

[Jdeharo]

Not sure if there is enough room to unplug regulator, can it be eliminated some where else?

 

[Jdeharo]

Not sure on the injectors, no black or white smoke out of the tail pipe at all.

 

[02CCSB]

CP3 can also leak out shaft seal...

 

[Jdeharo]

Can it leak that bad, I had about 4 gallons of oil/diesel in the crack case.
Can the pump be tested on the truck?

 

[mike diesel]

CP3 can also leak out shaft seal...

It will weep fuel into the valley long before it fills the oil with fuel.

 

[2004LB7]

Do you have enough room to unplug the pressure sensor? That will raise the pressure too

 

[Awenta]

That will raise the pressure reading but since the desired won't change from 5k neither will rail pressure.

Time for injectors.

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[Jdeharo]

Been running the truck, with the regulator unplugged, no dye or leaks anywhere. Balance rates OK.
What are the possibilities of the Cp3 seal been bad?

 

[tsd_billy]

My truck had perfect balance rates and the injectors were trashed at 117 k bc of the diesel i had access to. Get an ohms meter and check the ohms on your injectors through the harness plugs. They should read between .4 and 2ohms if if they are way high or show zero its time for replacements


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[tsd_billy]

http://youtu.be/cMEKBYXiJJc


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[Jdeharo]

Found some minute traces of dye around the base of the return neck on injectors 1,4 and 5, not a steaming leak, like I've seen in some videos, just a glowing ring around.
When they say an injector is cracked, does the metal actually breaks, or do the seals just go bad?
Also when you buy remanufactured injectors, do they just do new rings and some internal parts like I've seen in some videos.

 

[tsd_billy]

Found some minute traces of dye around the base of the return neck on injectors 1,4 and 5, not a steaming leak, like I've seen in some videos, just a glowing ring around.
When they say an injector is cracked, does the metal actually breaks, or do the seals just go bad?
Also when you buy remanufactured injectors, do they just do new rings and some internal parts like I've seen in some videos.

Dont buy remans get new injectirs from a company like fleece or exergy, they use all new bosch parts and exergy has great customer service

 

[tsd_billy]

And a cracked injector means its actually broken


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[mike diesel]

Dont buy remans get new injectirs from a company like fleece or exergy, they use all new bosch parts and exergy has great customer service

Every single "new" injector you buy, is actually a reman. There are no legitimate brand new injectors anymore, and haven't been for years.

 

[tsd_billy]

Every single "new" injector you buy, is actually a reman. There are no legitimate brand new injectors anymore, and haven't been for years.

True, however the worse mistake is buying from Pensacola diesel...Been there done that

 

[Jdeharo]

Placed my meter on the 200 range, all 8 injectors read between .02.5 and .02.9, I guess they are fine.
Not sure what else to look for.
Could it be possible that one of the supply lines was loose, and now that I've put them back to ran it without the covers it's not leaking any more.
I'm also running it without the turbo hoses, not sure if that makes any difference.