Massive amount of fuel in oil, how to find the culprit?

[fahrvergnuugen]

Hey guys, I need some help diagnosing what's wrong with a 2005 Dodge 2500 Cummins. Something is dumping a massive amount of fuel into the crank case; but I don't know if it could possibly be an injector, fuel pump or internal fuel line or something else entirely.

Back story: My 19 year old brother (16 years younger than I) bought this truck a year and a half ago. It ran fine and the body was in decent shape despite it having over 220,000 miles on it. He was driving it on the highway in the dark when it started making a ton of smoke and blowing oil out of the crank case vent. He wound up having the truck towed home. The next day it was clear that the tailgate and under side of the truck were covered in oil/fuel. The dipstick showed that it was way overfull. Because he spent all his money on buying the truck, he was forced to park it and put his beater Passat back on the road until he could save enough money to fix the truck.

Then last fall he and one of his best friends were killed in a car accident after his Passat went off the road and struck a tree. For weeks after the accident, parts that he had ordered for the truck were being delivered to my Dad's house. The parts were mostly front end suspension components that are worn out, as well as an aftermarket exhaust (priorities of a 19 year old kid I suppose).

It's been an long miserable winter to say the least, but now that spring is here I have decided I need to fix his truck. It's what he wanted, but never got to do.

Anyway, how can I figure out what the culprit is?
Is this a common problem? (I did quite a bit of searching but didn't find anything that matched exactly)
What are the chances that the motor is wiped out completely from the oil being diluted?

Thanks in advance for any advice you can offer.

 

[verk]

I'm a novice at injector diagnosing, but recently learning a lot because I need to replace mine. I'm going to guess a stuck pintle in injector. Any decent oscilloscope and person that knows how to use it can show both the pintle opening ( current waveform ) and the pintle closing ( voltage waveform ). Otherwise dealership who I think can determine this with their DRB 3 diagnostic tool. Others will know much more.

 

[TConver]

Really only two ways fuel gets in the oil. Either the injectors are leaking badly and washing down one or more cylinders into the oil or the CP3 pump has a seal leaking and is dumping fuel into the gear train in the front and ending up in the oil. I would change the oil and do a compression check and leak down check to see if you have a dead cylinder.

If it starts hard, needs the block heater run to start or ether to start it is likely the injectors leaking.

 

[TConver]

I'm a novice at injector diagnosing, but recently learning a lot because I need to replace mine. I'm going to guess a stuck pintle in injector. Any decent oscilloscope and person that knows how to use it can show both the pintle opening ( current waveform ) and the pintle closing ( voltage waveform ). Otherwise dealership who I think can determine this with their DRB 3 diagnostic tool. Others will know much more.

Only thing a scope is going to show is the coil getting charged and uncharged. The pintle is opened by moving a little ball that the is moved by the coil, then high pressure diesel actually opens the pintel. Just because the coil is working does not mean the pintel is working correctly.

 

[fahrvergnuugen]

Really only two ways fuel gets in the oil. Either the injectors are leaking badly and washing down one or more cylinders into the oil or the CP3 pump has a seal leaking and is dumping fuel into the gear train in the front and ending up in the oil. I would change the oil and do a compression check and leak down check to see if you have a dead cylinder.

If it starts hard, needs the block heater run to start or ether to start it is likely the injectors leaking.

I don't think it was starting hard. Can a bad pump result in that much fuel being leaked into the crankcase?
According to some videos I watched, there is an access plug on the timing cover to get to the pump bolt. I wonder if I used UV dye in the fuel if it would show up under that cover...

 

[TConver]

I don't think it was starting hard. Can a bad pump result in that much fuel being leaked into the crankcase?
According to some videos I watched, there is an access plug on the timing cover to get to the pump bolt. I wonder if I used UV dye in the fuel if it would show up under that cover...

Yeah a bad pump can put a lot of fuel into the oil. There is a cover that you open to take the CP3 off. Not sure if you could see UV dye in there or not. I do not think I would use it in the fuel though. That stuff leaves residue and it might not be good on injectors.

 

[verk]

Only thing a scope is going to show is the coil getting charged and uncharged. The pintle is opened by moving a little ball that the is moved by the coil, then high pressure diesel actually opens the pintel. Just because the coil is working does not mean the pintel is working correctly.

There are subtle, but still distinct parts to waveforms for the the pintel opening and closing. If the pintel is opening or closing it will distort the magnetic field and if your scope is good enough it will show it.

 

[cerberusiam]

To put that much fuel into the oil means the injector is stuck wide open and there is a hole in the piston, which would make a lot of smoke and rough running. The 3rd place fuel gets into the oil is a cracked injector body. At this point a new set of injectors is really needed, but, a compression test to see if the engine has to come out an be disassembled would be the first step.

 

[fahrvergnuugen]

Hi Cerberusiam, the truck doesn't seem to run rough or start hard, so I'm hoping that its not an injector issue. I think it was smoking because the oil was way overfull from fuel leaking into the crank case. I'm thinking this is a pump issue - it seems like a better fit given the symptoms?

 

[cerberusiam]

Could be a cracked injector body also, that is more common than the CP-3 seal leaking. You have to test and see what is wrong where. A cracked injector should show a haze with the valve cover off and engine running. The CP-3 leak should show will fuel running off the bottom of the CP-3 as there is a drain between the engine and pump. It might be plugged with crud and may need cleaned out to see leak.

 

[JKosten]

Really only two ways fuel gets in the oil. Either the injectors are leaking badly and washing down one or more cylinders into the oil or the CP3 pump has a seal leaking and is dumping fuel into the gear train in the front and ending up in the oil.

Don't forget that a loose or cracked crossover tube can leak also. Given that the truck had fuel under the body, I would check cylinders 4, 5 & 6 lines (most common to rattle loose, plus they have updated parts from Cummins) and make sure they are still tight. If you find a loose one, then also pull the cross over tube to inspect it.

 

[cerberusiam]

No, loose or cracked cross over tube will not put fuel in the oil. Cross over tubes are in the fuel return gallery.

 

[JKosten]

Ah, well that is good. Some of the larger displacement Cummins engines can leak into the oil system from a failed crossover tube if I recall.

 

[fahrvergnuugen]

I found this video:

I asked the poster and he replied that this leak filled his crank case in about an hour and a half, which jives with what happened with my brother's truck. Time to pull the valve cover and have a peak...

 

[cerberusiam]

Yeah, cracked injector body is by far the most common problem and the easiest to find.

 

[sag2]

After you pull the valve cover and start it, disconnect the FCA connector and any cracked injector body will be easier to find. It Will knock pretty good but will not hurt anything.

 

[Federico]

To put that much fuel into the oil means the injector is stuck wide open and there is a hole in the piston, which would make a lot of smoke and rough running. The 3rd place fuel gets into the oil is a cracked injector body. At this point a new set of injectors is really needed, but, a compression test to see if the engine has to come out an be disassembled would be the first step.

Hey, I'm having the same issue but not as bad have a 93 dodge with the 5.9 was great till the IP went and had it rebuilt by THD and ever since it has been getting fuel in the oil slower at first and more all the time..We turned up the pump from 90cc to 280 so it is definitely getting more fuel and it starts right up with no smoke and idles fine although before it was at about 800-900 rpm now it seems to have slowed down a bit..could it be that the injectors were old and with the added pressure from the IP and the amount of fuel the fuel is going right by to the crankcase? It has 352000 miles Lol..ANy help would be great as it got to the point I can't drive to due to ay too much fuel in the oil..Let me know

 

[fahrvergnuugen]

I bought a dye kit and UV light for $30 and put the dye in the fuel filter. Ran the truck for 30 seconds then pulled the valve cover.

#3 injector was leaking. Replaced that injector and the problem is solved.

It’s a cheap and easy thing to do, I suggest starting there.

 

[Federico]

Great Idea!

 

[Mikey-KE7LBB]

Hey, I'm having the same issue but not as bad have a 93 dodge with the 5.9 was great till the IP went and had it rebuilt by THD and ever since it has been getting fuel in the oil slower at first and more all the time..We turned up the pump from 90cc to 280 so it is definitely getting more fuel and it starts right up with no smoke and idles fine although before it was at about 800-900 rpm now it seems to have slowed down a bit..could it be that the injectors were old and with the added pressure from the IP and the amount of fuel the fuel is going right by to the crankcase? It has 352000 miles Lol..ANy help would be great as it got to the point I can't drive to due to ay too much fuel in the oil..Let me know

Your particular problem is not from an injector. It is most likely a failed lift pump or the injection pump seal.

Do you still have the stock lift pump, or did you swap it out for a 2nd gen one?? Reason i ask is the VE doesn't take more than about 15 psi to make the the seal leak.