oily fuel got me running bad

[st1100jack]

Hi folks,

I need some help on a problem I caused.

Some old farmer types that I know and work with, convinced me that a good thing to do for my diesel engine (my first deisel engine), would be to dump the used oil from oil changes into the fuel. They said that this would "help to lubricate the fuel pump", and that I would notice no change in how the truck performed.

This has not proven to be the case.

My truck is a 1998 K2500, 4x4, 6.5L TD, manual transmisstion. I added 3 gallons of used oil to a full tank of fuel, and it ran horribly. Lot's of smoke, a ton of clutch to start out, bad fuel economy. I ran it all through, and then I ran through a full tank of fresh fuel, treated with two cans of seafoam.

This truck used to start instantly, not smoke much, give 20mpg, and be impossible to stall. It's gotten better since the seafoam, but it's still a little smoky and prone to stall.

The check engine light is on, and I get the following two codes:

INJECTION PUMP METERING CONTROL A

and

TIMING REFERENCE HIGH RES SIGNAL A MALFUNCTION.


So, what do I do. Are there any sensors of a type that I might perhaps remove and clean up to help this?

I haven't changed fuel filters. Should I? Where are they?


Can anyone help?


--
Jack Smith
LaPorte, IN

[st1100jack]

The truck is a 1996 model, not a '98

[Hubert]

Well, unfortuneately the 94+ 6.5's (electronic controlled IP's and newer diesels in general) are much more sensitive to fuel quality, lubricity, viscosity etc. vs older machines. Read the forum well before you add anything other than an approved additive (GM says Stanadyne is really only one approved but others are good just not approved). Fully understand the mix ratios too and how they work. Some cleaners overdosed are going to be bad.

You need to change fuel filters first and check lift pump operation. And get some fresh fuel.

Fuel filter is back of engine in valley and there are many posts on it. The lift pump as well.

Read a few posts and then ask specific questions.

[More Power]

There are those who believe in using used motor oil as a diesel fuel supplement, from both as a fuel cost and a lubricity position. I've heard from some who use or have used very high concentrations of used motor oil or ATF in their mechanically fuel injected 6.2/6.5 without much in the way of a downside.

Personally, I don't like the idea much.... unless diesel fuel becomes $10/gal. Used motor oil contains far too much in the way of carbon particles, a lot of metal particles, caustic compounds and water. If used, it must be filtered at least down to 2 micron, and even then used at no more than a 5-10% mix ratio. The centrifugal oil filters could be the best and most cost effective way to filter the used oil.

The DS4 electronic fuel injection pump uses an optical sensor to establish fuel injection timing and calculate fueling. If the "fuel" is less transparent than diesel fuel, it could interfere with the optics. Secondarily, the DS pump is far more finicky than the earlier DB mechanical pump in regards to fuel quality. Personally, I wouldn't run used/filtered motor oil as a fuel supplement in a DS equipped 6.5 or high-pressure Bosch system unless it was an emergency situation or diesel fuel became unaffordable. Just my opinion...

Jim

[st1100jack]

The DS4 electronic fuel injection pump uses an optical sensor to establish fuel injection timing and calculate fueling. If the "fuel" is less transparent than diesel fuel, it could interfere with the optics. Secondarily, the DS pump is far more finicky than the earlier DB mechanical pump in regards to fuel quality. Personally, I wouldn't run used/filtered motor oil as a fuel supplement in a DS equipped 6.5 or high-pressure Bosch system unless it was an emergency situation or diesel fuel became unaffordable. Just my opinion...

Jim


I certainly won't be doing it again, I can tell you that.

The FI pump with optical sensor, where is it located? Is this sensor something I can remove and clean?


I guess I'll have to replace that fuel pump, and I've found that one checks lift pump by opening that purge valve at idle and seeing if there is fuel presssure. Is this accurate?

[DmaxMaverick]

I agree with Jim. Used engine oil is a bad idea in later models. I've used a lot of it in older Diesels, but would not in later electronic or high pressure systems.

The optical sensor is inside the IP. If fresh Diesel fuel doesn't clean it, it won't be cleaned. An attempt at R/R and cleaning would likely kill it. It can be replaced, but it is not likely your problem. If running fresh fuel doesn't clear it up, there's probably mechanical damage, or a previous issue has been waiting to come out, and the engine oil pushed it to the front. If you ran quite a bit of the oil through, the injectors are likely fouled.

Correct on the lift pump check. If you have flow/pressure at the water drain valve with the engine idling (if it keeps idling), the the LP is working correctly.

[st1100jack]

The optical sensor is inside the IP. If fresh Diesel fuel doesn't clean it, it won't be cleaned. An attempt at R/R and cleaning would likely kill it. It can be replaced, but it is not likely your problem.

Ok, good.


If running fresh fuel doesn't clear it up, there's probably mechanical damage, or a previous issue has been waiting to come out, and the engine oil pushed it to the front. If you ran quite a bit of the oil through, the injectors are likely fouled.

Is there a way to unfoul them? More Seafoam, maybe at a higher concentration?

[DmaxMaverick]

Ok, good.



Is there a way to unfoul them? More Seafoam, maybe at a higher concentration?

Time. If they clear at all. More Seafoam won't help, and concentrations higher than the label recommends can be worse than none at all. Much depends on why, if they are in fact fouled. Could be particulate (soot and/or metallic) or additive related. The engine oil additive package contains chemicals that prevent burning, and promote film strength and adherence. All properties we fight to keep out of our fuel. The only advantage to engine oil is its lubrication ability, but the negatives outweigh the advantage. I suggest an additive such as Stanadyne or Power Service (among others) to help clean things up. But, don't do it until the Seafoam has run its course. Mixing additives can also have negative results.

[st1100jack]

Correct on the lift pump check. If you have flow/pressure at the water drain valve with the engine idling (if it keeps idling), the the LP is working correctly.


I just checked that (lunch break here @ work). Pressure seems strong, truck condinued to idle just fine.

The fuel pumping out of thatvalve was about as black as the waste motor oil. Is this normal?

[DmaxMaverick]

No. That doesn't sound normal. You probably still have enough oil in the fuel to darken it. It doesn't take much. You can drain the tank, but I wouldn't. Just run it down to empty and fill it (repeat). Eventually, it will dilute back to normal.

[st1100jack]

I'll get a new filter Monday; working 16hr. days all weekend.

As mentioned, I did the lift pump check yesterday, when I saw the blackened fuel. When i first opened the valve, I got a bunch of brownish frothy oil/water mix garbage, which then became straight fuel as I let it run.

Purging this gack out of there seems to have made a difference, as I now have a lot more of my off-idle pull back, and need less clutch to start out.


I'll change that filter, and keep on truckin' for a while and see if it cleans up. May try that Power Service additive too.

[jbplock]

Glad to hear you seeing some improvement .. In addition to the other good suggestions offered you might also try some FPPF injector cleaner (http://www.fppf.com/dieselfuelinjectorcleaner.asp) .. I find it available at truck stops.. It's also available from on line vendors (google "FPPF injector cleaner")

[polejockey65]

I have a friend that talked me into burning some used motor oil to. about a gallon in a full tank. now she spitts sputters and she is very very mad at me. i have changed the fuel filter at the have way mark now she's running better but still hard to start and blows lots of smoke. i filled her up about half way down and she's still mad but running better. but the loss of power worries me. i think the lift pump is bad . she quit when i opened the pep-valve when the filter was changed.
Now for my question:
will it be ok to run with the bad lift pump till i get the motor oil flushed out. i am at a 1/2 tank now, 2nd time. Or should i run another tank through to clean her out then change it ??
Thanks everyone again
Brian