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I have heard about it but never seen it personally... until today. We took a fuel sample which is not quite black but tinted dark enough to know what it is. The customers only complaint on his 1997 E450 with 140,000 miles is that it is using 3 to 4 quarts of oil a week. No smoke, no leaks.

 

It may be light because the oil was just changed and he has probably filled the tank since changing it. My guess.

 

I understand this indicates an injector problem. Have any of you run into this before? Does anyone know exactly what causes this? O-rings or internal injector issues?

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I have run into this alot on the older return fuel systems Keith. What I do is put a shit load of engine oil dye into the crankcase and run the engine untill the crankcase gets low. May have to let the customer drive it for a day or two or drive it home at nites yourself. Once the crankcase is low, pull the fuel filter lid off and shine inside with a black lite. If you see the dye in the fuel, You have an injector O-ring problem. The cause is usually the injector O-rings. Do them all. Obviously, right? I have diaged them like this for years and it works great.

 

Too bad it doesn't work on the newer returnless sytems theough. The old return systems were very easy to diag this way.

 

Hope this helps.

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Dwayne's correct, but I don't go into the diagnostic mode, I just change the o-rings. 97% of them will be the center o-ring on the injector leaking and causing the oil to seep into the fuel galley, where it returns to the tank on a the first generation truck. 3% of them will be bad injectors. There is a passage inside the injector where the same problem can occur, but this is pretty infrequent.

 

You may be able to see this as an increased IPR command in scan data, it should be between 9-11% at a hot idle. With the slow rate you're using oil it probably won't show up unless the upper o-rings are leaking, too.

 

Put 8 sets of o-rings in it and you should be fine.

 

Ugh! There he is again! /forums/images/%%GRAEMLIN_URL%%/smirk.gif

 

Posted Image

 

Good Luck! /forums/images/%%GRAEMLIN_URL%%/smirk.gif

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Lost count on how many of these we did down South with the heat index and all. Had quite a few that would get injector cups as well if they couldn't be cleaned up with the brushes.

 

Had a '94 that was so old it was still obd 1, which required cycling the key and throttle pedal and so on to do any testing, found it had #8 injector bad. The injector was froze in the cup and took such force to remove it that it pulled the cup out with it then proceeded to flood the engine and exhaust system with coolant. Craziest thing I ever saw on one of these, the thing was welded together.

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Keith, when you pull the injectors out there couldn't be a better time to bench test them. This will eliminate any guess work.

Bench test? The only way I know of is with a HEUI machine, and I don't consider them accurate. Can you elaborate?

 

Thanks!

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Bruce, Ford sent us this tool that you put the injector into a cup of sorts which connects to something... I think there is a hydraulic pump... tests for leak-down. I remember there being something for the IPR as well. Its all in the back of my shop cabinet collecting dust. I'll pull it out and snap a pic for ya. Maybe I'll get you a more accurate description too. /forums/images/%%GRAEMLIN_URL%%/wink.gif It arrived along with that 7.3L CMP testor... /forums/images/%%GRAEMLIN_URL%%/rofl.gif

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The tool works awsome. Get to know it and it will become a valuable friend. You can find this test procedure in the heading below: 2002 PCED On Board Diagnostics II Diesel SECTION 4A: Diagnostic Subroutines F-250-550 Injector Performance Test. Keith, I don't know what the hell it is I do wrong, but I can never get the pictures to come through. Think you could help me out with this?

 

 

 

 

2002 PCED On Board Diagnostics II Diesel SECTION 4A: Diagnostic Subroutines — F250-550 and E-Series

Procedure revision date: 05/23/2005

 

--------------------------------------------------------------------------------

 

Injector Performance Test

Purpose

This procedure provides the ability to verify the internal component integrity of the 7.3L diesel fuel injectors.

 

The following Diagnostic Tests must be completed before this procedure:

 

Hard Start/No Start or Performance Diagnostic Guides

KOEO Injector Electrical Self-Test (Buzz Test)

KOER Cylinder Contribution Test

Injection Control Pressure (ICP) Test (Oil Aeration)

Recommended Procedure

 

Note: Testing of new fuel injectors prior to installation in the engine will cause inaccurate test results.

 

Note: Before removing the suspect fuel injector(s), remove the valve cover(s) and monitor the fuel injector spill spouts for oil flow while the engine is running at idle. The amount of oil flowing through the top of the fuel injector is directly proportional to the amount of fuel flowing out of the tip. If low oil flow is observed at the top of the fuel injector, fuel flow out the tip will also be low providing a rough idle condition.

 

 

 

 

 

Item Number Description

1 — Calibrating injector adapter

2 — Calibrating injector O-rings

3 — Fuel injector tester

4 — High-pressure oil port

5 — Fuel port

 

Remove the suspect fuel injector. For additional information, refer to the Workshop Manual Section 303 Fuel Charging and Controls.

Inspect the three external fuel injector O-rings for wear, cracks and cuts. The O-rings may be repaired separately from the injector assembly. Install a new O-ring(s) as necessary.

Note: A vacuum pump with a minimum 0 - 28 in Hg gauge is required.

 

Note: Inspect the three calibrating injector O-rings for wear, cracks and cuts. Install a new O-ring(s) as necessary. The calibrating injector O-rings are the same O-ring utilized by the 7.3L fuel injector.

 

Verify the fuel injector tester and vacuum pump as follows:

 

 

 

Item Number Description

1 — Calibrating injector adapter

2 — Fuel injector tester

3 — Fuel port

4 — Fuel injector retaining bolt (2)

 

Install the calibrating injector adapter into the fuel injector tester and make sure it is properly seated. Use the fuel injector retaining bolts from the engine and torque the retaining bolts to 13 Nm (120 lb/in).

Connect the vacuum pump to the fuel port and apply 25 in Hg of vacuum. Monitor the gauge for 6 minutes. Verify there is no vacuum loss. If vacuum loss is present, inspect the fuel injector tester, fittings, O-rings, vacuum hose and vacuum pump for leaks. Repair as necessary and repeat the test.

 

 

 

 

Item Number Description

1 — Fuel injector

2 — Fuel injector tester

3 — Fuel port

 

Once the tool function capability has been verified, lubricate the O-rings of the suspect injector with clean engine oil. Install the suspect fuel injector into the fuel injector tester. Use the fuel injector retaining bolts from the engine and torque the retaining bolts to 13 Nm (120 lb/in).

Note: Some fuel injectors may exhibit minimal vacuum loss. Vacuum loss less than 1/2 in Hg is acceptable and does not indicate a damaged fuel injector.

 

Connect the vacuum pump to the fuel port and apply a minimum of 25 in Hg vacuum. Monitor the vacuum gauge for signs of vacuum loss. If vacuum loss is greater than 1/2 in Hg within 6 minutes, the fuel injector is damaged. If vacuum loss is less than 1/2 in Hg, leave the vacuum pump connected to the fuel port and GO to step 6.

 

 

 

 

Item Number Description

1 — High pressure oil port

2 — Fuel port

3 — Spill port

 

Monitor the vacuum pump while connecting 689 kPa (100 psi) of regulated shop air to the high-pressure oil port. If the vacuum loss is affected by the presence of air pressure, the fuel injector is damaged. If no vacuum loss is present, GO to step 7.

Check for air leaks possibly indicated by whistles or continuous bubbles at the spill port indicating the fuel injector is damaged. If noncontinuous bubbles are present at the spill port, the fuel injector is not damaged.

Vacuum loss indicates internal injector scoring which may cause a rough idle or low power concern.

 

Vacuum loss that is affected by the presence of air pressure on the high-pressure oil side indicates internal O-ring damage. This O-ring separates the fuel from the oil and may contribute to excessive oil consumption.

 

No vacuum loss on the fuel side with an air leak from the high-pressure oil side (top) indicates a damaged poppet valve or seal.

 

Repeat steps 4 - 7 (calibration of the fuel injector tester is not required) for the remaining suspect fuel injector(s) as necessary.

Tools Required

Lubricants Item Specification

SAE 5W-20 Premium Synthetic Blend Motor Oil XO-5W20-QSP WSS-M2C153-H

 

 

Fuel Injector Tester

Vacuum Pump

 

I will post the tool numbers in the morning for you Bruce.

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Thanx for saving me the time. You give a positive report on the use of the tool, perhaps I should give it more respect? Funny thing, we don't see many 7.3's any more but this truck might provide an opportunity to try the tool.

 

We are waiting for an approval for the cost of a set of injectors if needed. At minimum, we need more diag time however the dye trick won't eat up any time and I have some dye laying around. At least by doing that we will know for sure the oil is going into the fuel before we even think about pulling the injectors. The tech says the truck runs well despite having the mileage it does. Usually the 7.3's we see have been sipping crap fuel and water through clogged filters.

 

Thanks for the help guys!

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