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Lyrch
10-26-2015, 21:30
So new to this forum I've been looking around to find out about this fuel issue in my 02' 2500hd ,I'm getting a lot of fuel into my oil the injectors were changed about 10k miles ago now I am a mechanic but I really don't do diesels according to a friend of mine ,who did the injectors at his shop,there is no way to find this fuel leak without replacing everything in the fuel system and by the time I'm done doing that the motor will just spin a bearing and need to be replaced anyway so I should just junk the truck. I kinda like my rig so I'm trying to figure the best course of action any help or suggestions would be greatly appreciated.

Lyrch
10-26-2015, 21:43
Oh and just for a side note the injectors were replaced with factory gm parts ,I have also read that the return lines are prone to leaking after injector replacement that being said is there a way to diagnose this issue without pulling the valve covers?

CoyleJR
10-27-2015, 09:00
First don't junk the truck and second get another mechanic. Third e-mail John Kennedy and ask for guidance and buy any needed parts from him. John is a advertiser and regular contributor to the DP. Additionally, if you are a gas auto mechanic you won't have any trouble fixing your diesel truck with help from the DP contributors.

Good luck

Kennedy
10-27-2015, 13:08
There are really only 2 common ways (third is a very rare stretch) to get fuel in the oil.

1) Cracked/leaking/defective injector body
2) leaking return lines (installation error)
3) overpressurization of the return side due to plugged tank orifice (VERY RARE)

If it did not develop immediately after the work was done then I'd say it's probably injector body related. Later injectors do not tend to crack so this has not been a common issue since the 2001-2002 era bodies were used. These bodies are not used by Bosch for remans, but may be re-used by others.

I will add that MANY MANY of these trucks have been driven to the point that the fuel/oil mix sprayed all over under the truck and down the road and I can't think of one that I have ever heard reported to have wrecked the engine.

stockcar79
08-24-2016, 08:46
add oil die to you fuel then you can see the leak with a black light

stockcar79
08-24-2016, 08:52
also did he clean the fittings on the inj I have seen them leak (high press) they should have been beed blasted

More Power
08-24-2016, 11:34
While very rare, the high pressure pump can also be a source for a fuel leak into the crankcase.