runs rough, fuel in oil, no codes

lraffe1 · January 25, 2008

Truck came in with a complaint of runs rough and regens every fifty miles. I found fuel in oil. I changed the oil and took care of the running rough. I then tried to find the source of leak and found no codes, fuel trims normal, passes power balance and high pressure fuel test. Has any one encountered this and have any suggestions.

GregH · January 26, 2008

Yes, I have.

Had one that made a quart of oil every 200 miles. Ran high pressure tests, all pass. Ran testing with the valve covers off, no leaks observed. Added oil dye to fuel filter housing, ran high pressure tests, no dye visible. No codes, fuel trims ok. Hotline said slam a pump to it. Returned to the customer, 1000 miles later had 5 quarts of fuel in the oil.

International engineer was called in. He put 200 miles on the truck and measured the oil. No change. He said it was due to customer's driving habits and no repair was possible... Heh..

Customer traded out of the truck. We sold it to someone else who has never owned a diesel before, and just assumes that these issues are inherent to diesels. Heh, again... At the new customer's last oil change, 20 quarts came out....

Yeah, I don't know where the fuel is coming from. But it's not the pump...

The International engineer and I worked on a new testing procedure while he was here. We applied 80psi of air pressure to the fuel return passages in each head and watched the pressure decay rate. Basicaly, we drilled and tapped a hole in the end of an open banjo bolt, and JB welded the perpendicular holes shut. Then rigged a pressure gauge and a ball valve to the banjo bolt and put regulated shop air to it. There should be no or very little decay. After the fact, we learned that International says over 20 psi of air pressure applied in that way can damage the injectors. Ooops...

Anyway, there were a few other things we talked about. I'll need a bit more coffee before we go into all that, though....

Keith Browning · January 26, 2008

I wish I could remember the exact numbers quoted but one of the boys at the HotLine told me that it is normal for these engines to make a little oil but the severity was dependent on the usage and driving habits. I think the number was 2-3 quarts per service interval, say a 5,000 mile oil change interval.

Comments like these trucks shouldn't be driven by people who are not hauling and or towing and that Ford wants to see people stop buying these things and using them as grocery getters. Idling and short trips will load these engines up and I assume this is what he was eluding to. Perhaps there is more going on with the regeneration process than we realize.

So, what are we to think when we hear accounts like this or the ones that Greg has shared? I have seen a few oil changes that were a good 4 quarts more than they should have been... discovered this on trucks that were in for the excessive white smoke during regeneration issue.

I had one that I drained 23 quarts out of the crankcase but that engine self destructed as I posted here. If some fuel dilution is to be expected then how much should we expect? Perhaps now we might re-think the usage of oil sampling and testing, on the 6.4L engines anyway.

I don't have an answer for you but I might focus on the frequent regenerations first if I were you. If you can diagnose that and return the regeneration frequency to more normal numbers I would expect that your oil dilution concern will diminish.

lraffe1 · February 18, 2008

I thought I would give an update on what I found. After talking to hotline I checked the maf and exh back pressure. They both checked okay. However, on test drive I found two cyl dropping out under load. I then decided to remove valve covers and check for leaks. I did not find a leak in fuel system. I replaced the two inj, blead system and retested for fuel leaks and passed. I returned to costumer and asked him to bring it back in 1500 miles to check oil. After giving back to costumer I went to a training class and talked to the instructor. He suggested to remove all eight inj and install them facing up, unplugged and crank the eng over and look for fuel leaking.

OHNO60 · February 18, 2008

knew international f'd up installing them tip down! why didn't they just install them up from the beginning,sorry dude had to. same issue here more than one truck at least 10 quarts over with fuel. hotline told me to slam a pump on 2 of them too. just waiting for them to come back again running like crap. one thing i did notice is when they run like crap only cylinder 1 has a rear high short-term fuel reading. all the rest normal. hotline was concerned about the short term high. long story short over filled crankcase. not sure they know yet.

LARRY BRUDZYNSKI · February 19, 2008

Quote:

He suggested to remove all eight inj and install them facing up

Not sure what you mean by face up, does this mean to rotate them 180 degrees in the head? I thought that injectors can only go in one way.... /forums/images/%%GRAEMLIN_URL%%/scratchhead.gif

Jeff_ · February 19, 2008

nope, it means remove the injectors and set them upside down with the tips pointing away from the engine, reconnect the fuel lines, but leave the electrical connections unplugged. Then crank the engine while watching the injector tips for leakage.

OHNO60 · February 19, 2008

SOUNDS LIKE THE ENGINEERS DONT EVEN KNOW. ARENT YOU SUPPOSED TO REPLACE ALL THOSE LINES NOW THAT THEIR DISTURBED? TELL YOU WHAT YOU HEAVY TRUCK TECHS CAN RELATE TO THIS. THE 07 ISX HAS AN AFTER TREATMENT INJECTOR AFTER THE TURBOCHARGER OUTLET. IT FIRES INTO THE EXAUST NOT THE CYLINDERS LIKE OUT 6.4 SAUDI ARABIA SUPPORTER. WHY THE HECK DIDNT THEY GO THAT ROUTE? THAT WOULD BE THE END OF THEIR THEORY OF "REGEN OIL GROWING". SEEMS A LITTLE DIFFICULT TO EXPLAIN TO AN OWNER WHO SPENT OVER 50,000 CLAMS.

lraffe1 · February 20, 2008

I guess I should have worded it a little different. He told me to face them up, unplugged with old lines and to replace the lines when installing inj. Also talked to customer and he cliamed his fuel mileage went up 2 mpgs.

cochran · March 12, 2008

Does the procedure go into any safety aspects? If you connect these injectors pointing out of the cylinders to perform this test, you are exposing yourself and your immediate environment to very high pressure diesel spraying all over the place. Is this smart?

The comment is correct about the reinstallation. The pipes are single-use, and this is important. Its also vital to use a backing wrench during install and removal. The high pressure connector on the injector has a crush washer at the bottom, and if you crack the seal you have a high potential for creating a leak.

Jim Warman · March 12, 2008

My last RO of the day.... I rolled one of these into the shop..... oil level is about ten or so inches high.... Degas bottle is empty but, looking at the bottom corner of the rad, this is a Job 1 truck and this means just one more line on the RO....

We shall see what tomorrow reveals...

BrunoWilimek · March 12, 2008

Does the procedure go into any safety aspects? If you connect these injectors pointing out of the cylinders to perform this test, you are exposing yourself and your immediate environment to very high pressure diesel spraying all over the place.

This proceedure is actually in the PCED. The amount of fuel leaking out is actually quite minimal as the proceedure involves disconnecting the injector main connectors at the front of the heads and only cranking the engine using the starter.