IK1200990 ­ MaxxForce 7 Fuel Dilution Diagnostics

Page 1 of 4

SB-10054694-9950

Countries:

Document ID: IK1200990

Availability:
Major System:

Revision:
ENGINES Created:

0
10/17/2013

Current Language: English

Last Modified: 12/27/2013

Other Languages: NONE

Author:

Viewed:

Aaron Mimbs

96
Less Info

Coding Information

Hide Details

Copy Link

Copy Relative
Link

Bookmark

Add to Favorites

View My
Bookmarks

Print

Provide Feedback

Helpful

Not Helpful

1

0

Title : MaxxForce 7 Fuel Dilution Diagnostics
Applies To : All MaxxForce 7
DESCRIPTION
Over time the engine oil will naturally dilute with fuel over the recommended service interval due to
post injection during active and passive regenerations. Mild dilution is acceptable, if this is the case then there is no
concern and warranty will not cover any diagnostic procedures performed on the unit. Dilution issues are evident when
the engine is making excessive amounts of oil that is noticeable in a short time frame of oil life. Before performing any
diagnostics make sure the ECM calibration is current and any open AFCs have been performed. In severe dilution
cases the enclosed high pressure fuel system could potentially have developed a leak over time putting fuel into the
oil. Check with the customer and his oil service habits, if they are not in line with the recommended service as outlined
below have the oil changed and release the unit for the customer to monitor the level.
2007-2009 MaxxForce 7: Make sure AFC 12948 has been completed. The new calibration and AFC was released to
address the fuel dilution problem and has been very effective in doing so. The required oil service interval for this
engine is every 10,000 miles OR 350 hours whichever comes first. Please see the operator’s manual for more
information.
2010- Current MaxxForce 7: Make sure the engine calibration is up-to-date and the required oil service interval for
this engine is described in the chart below. The interval is contingent on average MPH and MPG. Please see the
operator’s manual for more information. For low oil pressure concerns please see IK1200744

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 1/2/2014

IK1200990 ­ MaxxForce 7 Fuel Dilution Diagnostics

Page 2 of 4

In extreme cases the oil level can visibly rise after a test drive or upon arrival to the dealer the oil maybe
several inches over full and will have low viscosity. If this is the case then the following diagnostics should be
performed.
SYMPTOMS
·
·
·
·
·
·

Low Oil Pressure
Increasing Oil Level
Black Smoke
Excessive Oil Carry Over into Intake
High Crankcase Pressure
Engine Vibration

TROUBLESHOOTING STEPS
1.

Update ECM calibration if needed and note which calibration is in the ECM before and after the update

2.

Check the oil level and note the level

3.

Confirm oil is diluted with fuel
a. Perform Paper Drop Test: Sample the oil and drip some onto a piece of paper. If a clear ring forms around the oil this is
the diesel fuel separating from the oil
i. Diesel is Present: Sample the oil and send it out for testing (Keep results and if a case file is needed scan them
and attach to the case file) and proceed
ii. Diesel is NOT Present: Proceed to steps 4 and 5, review service records drain the oil to a proper level and release
the unit back to the customer to monitor the level

4.

Check for active and inactive DTCs

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 1/2/2014

IK1200990 ­ MaxxForce 7 Fuel Dilution Diagnostics

Page 3 of 4

5. Request the latest service record from the customer and note how many hours and miles are on the current
oil change (Ensure Proper Maintenance Habits)
6.

2007­2009 MaxxForce 7 Inspect the breather type and take note of which type it is (Open or Closed)
a.

Non-Bus Application: Install Open Breather Kit 1889886C91 if needed (Instructions)

7. Inspect the inlet of the Charge Air Cooler (CAC) with a flash light and mirror for plugging and oil
contamination
a.
b.

8.

CAC Plugged/Dirty: Attempt to Flush CAC (Replace if needed) then proceed
CAC Not Plugged: Proceed to next step

Inspect the Turbo for Oil/Fin Damage/Shaft Play
a. Turbo Damaged or Pushing Oil: Perform all necessary steps in diagnosing/replacing the turbocharger(s), cleaning the
engine, and inspecting the aftertreatment. Diagnose Turbo Following IK1200535 for Oil Leaks Inspect exhaust side for oil. If
all seems okay then clean the turbocharger (Cleaning Kit 1891576C91)
b. 2007 – 2009 MaxxForce 7 Perform Diesel Oxidation Catalyst Cleaning Procedure:Reference IK1200478, it will
automatically create a snapshot of the procedure (Attach to case file later if needed) If DTC 1213 Remote

Throttle Signal Out of Range Low is Active after running the cleaning see IK0800323 to clear the code
Make sure the oil is at a proper level and mark the dip stick. Road test for 30 miles and if needed perform a stationary
regeneration. Let the engine cool down and then recheck oil level to see if it has risen (NOTE:Oil expands when it is
hot)
If the oil level did NOT rise then in extreme dilution cases request customer approval for an oil service however if the
oil is already new and is heavily diluted contact CSE and request a good will warranty coverage on oil service. Give it
back to the customer to monitor levels.
If the oil level is still rising get Crankcase Pressure and Blow­by (2010 ­ 2013) readings at Idle and Wide Open Throttle
(WOT). If the readings performed are out of specification proceed with a manual compression test. If Crankcase
Pressure on the 2010 - 2013 MaxxForce 7 is out of specification and Blow-By is in specification then the crankcase
breather is most likely plugged.
(NOTE: Use the specification defined in these articles, the Blow-By test is only for the 2010-2013 MaxxForce 7
and is similar to the Crankcase Pressure test on the 2007­2009 MaxxForce 7. The crankcase pressure test on
the 2010­2013 MaxxForce 7 is different and is meant to test the crankcase breather for plugging. There is
always CCP and Blow-By and they are always greater at WOT, Gauges do break)
2007 – 2009 MaxxForce 7:Please see IK1200881
2010 - Current MaxxForce 7:Please reference the diagnostic manual EGES485 under Performance Diagnostics >>
Special Test Procedures >> Blow­by Test & Crankcase Pressure Test
If within specification remove the valve covers and then reassemble needed components to run the engine. Connect
separate clean fuel source and add CUMMINS dye to the fuel. Allow the engine to idle to operating temperature and
watch for leaking injectors with a black light. (We find that Cummins dye and a black light work the best for leak
detection)
If leaks are found replace the component and recheck for leaks if all is well reassemble and recheck for dilution. If a
leak is not found run the Standard Test in ServiceMaxx this will increase FRP which increases the chance of a leak.
Inspect ALL high pressure fuel system connections and fittings including the FRP sensor, injector bodies, both jumper
tube ends, and the high pressure rails. If no leaks are present brake stall the engine and watch for leaks, shut down
the truck and feel around all the high pressure fittings and check your finger for dye. If no leaks are found pull the High
Pressure Fuel Pump cover and reassemble clean off any fuel present from removing the lines and perform the same
tests while looking for leaks at the pump.
If no leaks are found and this unit is still gaining oil please open a case file with all the above information.
Hide Details

Feedback Information
Viewed:

95

Helpful:

1

Not Helpful: 0
No Feedback Found

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 1/2/2014

IK1200990 ­ MaxxForce 7 Fuel Dilution Diagnostics

Page 4 of 4

Copyright © 2014 Navistar, Inc.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 1/2/2014