Engine Oil Consumption - Diagnostic Procedure
OIL CONSUMPTION - 6.9L DIESEL - SERVICE DIAGNOSTIC PROCEDURE
Article No. 87-3-19
LIGHT TRUCK 1983-86 E-SERIES, F-SERIES ISSUE:
Oil consumption for the 6.9L diesel will vary with the way the vehicle is driven, the vehicle load, or normal variations that may occur from one engine to another. This is especially true during the first 7,500 miles (12,000 kilometers) when the new engine is being "broken in" or until certain internal engine components become conditioned. Heavyduty operation (such as trailer towing, heavy loads, large frontal areas, sustained high-speed driving, sustained driving in lower gears, frequent or extended idling, or frequent short trips) may use more oil. Vehicles in normal usage should get at least 900 miles per quart after the first 7,500 miles (12,000 kilometers). Vehicles in heavy-duty operation, as defined above, may use a quart of oil every 750 miles (1,200 kilometers). On vehicles with extended idle, a quart of oil every 50 gallons of fuel may be consumed. Vehicles loaded past the maximum recommended GCW of 14,000 lbs. or with over 60 sq.ft. frontal area may use more than a quart of oil every 750 miles (1,200 kilometers).
ACTION:
To resolve complaints of excessive oil consumption, use the following service diagnostic procedure.
NOTE: This TSB article supersedes TSB articles 85-7-16 and 83-23-15 in their entirety.
1. Make sure of the correct oil usage and service intervals.
NOTE: ONLY lubricating oils conforming to Ford specification ESE-M2C153-C and API service categories of both SF and CD (SF/CD) are recommended for use in the 6.9L diesel engine. Oils labeled as only SF, or only CD are not suitable because they could damage the engine. SF/CC oils are no longer recommended. While these oils are adequate, it has been found that SF/CD oils provide superior engine and oil life.
See the 1987 Ford Owner's Guide 6.9L Diesel Engine Supplement for proper engine lubricating oil usage.
Also refer to TSB Article No. 86-10-14 for important information on oil change interval and soot levels.
The use of Ford's Motorcraft Super Duty 15W40 SF/CD Engine Oil (green can), or equivalent, is recommended as the oil that meets the lubrication requirements of the 6.9L diesel engine including beneficial qualities not yet covered by API classification. Also, where the issue of severe service operation may be a factor, an oil change interval of every 250 to 300 gallons of fuel consumed, or 125-150 hours of operation (whichever occurs first), may be used as a guideline.
2. Inspect for external leakage and service as required.
3. Inspect the intake port of the intake manifold for dirt and debris. Sand and/or environmental debris at this location would be an indication of poor maintenance and/or air induction sealing. Environmental debris, such as sand or dirt ingested into the engine will speed up internal engine wear causing increased oil consumption. Repair the cause of any contamination before proceeding. A presence of oil wetness in the intake manifold is normal.
NOTE: The installation of aftermarket turbocharger kits or aftermarket air cleaner assemblies may increase oil consumption.
4. Check air cleaner restriction. If air cleaner restriction is more than 24 inches of water at 3,300 RPM at no load, replace the air cleaner element.
5. Check installation of the oil gauge (dipstick) tube. The oil gauge pilot tube (lower) E3TZ- 6754-E on F-Series trucks should be fully pressed into the engine block. The oil gauge tube (upper) E5TZ-6754-D should bottom in the pilot tube assembly. The dipstick, when properly installed, will seat on the upper end of the tube assembly. Improper assembly of the oil gauge tube or incomplete installation of the dipstick may cause an incorrect oil level reading. This incorrect reading could be mis-diagnosed as oil consumption. Correct any problem found before proceeding.
NOTE: F-Series engines, after serial number 173531, use the two-piece oil gauge tube described above.
6. Change the oil and oil filter. Use Motorcraft Super Duty 15W40 SF/CD Engine Oil (XO- 15W40-QSD) unless outside temperatures are expected to be repeatedly below 0~F (18~C) in which case a 10W30 SF/CD engine oil should be used. Add 9 quarts of oil (one quart short of the specified 10 quarts). Run the engine until operating temperature is reached and the oil filter is full.
7. Shut down the engine for 15 minutes to allow oil to drain back to the oil pan. Check the oil level (the dipstick handle "loop" must be toward the valve cover). The 9 quart level should be midway between the "ADD" and the "FULL" marks. Add the 10th quart of oil, and check that the oil level is within 1/16 inch of the "FULL" mark. If the oil level is not within 1/16 inch of the "FULL" mark, refer to TSB Article No. 85- 25-19.
NOTE: All oil level checks must be made after the engine reaches operating temperature, and after the 15 minute oil drain-back period.
8. Make arrangements to have the customer bring the vehicle in when it is necessary to add oil. Oil should only be added when the oil level falls below the "ADD" mark. Track consumption for at least 2,000 miles (3,200 kilometers) or until 4 quarts of oil are consumed, whichever occurs first. If a high oil consumption rate is confirmed, continue diagnosis.
9. Check crankcase pressure per Test Step EPC. 12, page 24-44 of the 1987 Engine/Emissions Diagnosis Manual, Volume H. Connect the pressure side of the gauge in the Rotunda Pressure Test Kit 014-00702 to the 5631 Adapter from same kit. Replace the oil fill cap with adapter. Remove the crankcase depression regulator (CDR) valve per Truck Shop Manual, Section 22-08. Plug the CDR opening in the valley pan and make sure that the dipstick is seated in the tube. The gauge should read a maximum of six inches of water on a warm engine operating at 3300 RPM with the accessories turned off. If the pressure is not within the specification, there is an internal engine concern. Proceed to Step 14. Excessive crankcase pressure can result in increased blow-by gas flow through the crankcase depression regulator valve and increased oil consumption.
10. With the crankcase depression regulator valve still removed, look through the vent hole in the valley pan to see the oil baffle which is welded to the bottom side of the valley pan. Insert a screwdriver through the vent hole and push lightly against the baffle. Excessive movement of the baffle may mean that one or more of the welds which hold it to the valley pan have broken. This condition could result in excessive oil carry-over through the CDR valve into the intake manifold and cause a high rate of oil consumption. If the baffle is loose or has fallen out of position, replace the valley pan per Truck Shop Manual, Section 22-08. Reinstall the CDR valve.
11. Remove choke from air cleaner tray assembly.
a. Remove the air cleaner assembly from vehicle.
b. Place the tray only, open side up, on two supports (e.g., two 2x4's) so the alignment tabs and water drain tube will not be damaged.
c. Inside the air cleaner, there are six spot welds which secure the choke to the tray bottom. Remove the spot welds without causing holes through the tray. The methods to remove the spot welds are:
^ A deburring tool used on a hand-held drill motor.
^ A spot weld cutter used on a hand-held drill with a drill stop. Center punch the spot welds first.
^ A 9/32 inch drill bit used on a handheld drill motor with a drill stop. Center punch the spot welds first.
d. After making sure all the spot welds are removed, turn the air cleaner tray over and place the tray lip on two supports to protect the internal baffle.
e. Using a board and hammer, drive out the choke and wing bolt guide assembly.
f. Deburr all holes and sharp edges.
g. If a through hold occurred in the tray at any of the spot weld locations, clean the locations on the underneath side of the tray. Using a putty type epoxy, seal the hole(s) by placing the epoxy on the tray's bottom side. MAKE SURE the seal is larger than the hole to guard against ingestion into the air cleaner and engine.
h. Clean the metal filings and shavings from the tray.
i. Spray the unpainted surfaces with an enamel base, black paint.
j. Reinstall the air cleaner assembly.
12. Change the oil and oil filter again as described in Steps 6 and 7. Make arrangements to have the customer bring the vehicle in when it is necessary to add oil, and track oil consumption for at least another 2,000 miles (3,200 kilometers) or until 4 quarts of oil are consumed, whichever occurs first.
13. If oil consumption continues to be high, inspect the valve seals. All intake and exhaust valves should have a nylon stem seal fitted to the valve spring retainer. All intake valves should have a spring loaded umbrella type seal fitting over the top of the valve guide. Inspect the umbrella seals for missing springs or nicks on the sealing edge. Replace all valve seals and re-evaluate oil consumption rate.
See TSB Article No. 84-19- 20 for the revised valve spring assembly installation procedure.
14. If the oil consumption concern is still not corrected, disassemble the engine to check valve guide clearances and condition of piston rings and cylinder walls. Service per Truck Shop Manual, Section 22-08.
NOTE: Replacing piston rings and re-honing the cylinder walls will not improve oil consumption when a concern has NOT been identified.
