Lincoln Aviator: Accessory Drive - 3.0L EcoBoost / Diagnosis and Testing - Accessory Drive
Inspection and Verification
-
Verify the customer concern.
-
Visually inspect for obvious signs of mechanical damage.
Visual Inspection Chart
Mechanical
|
-
Damaged or contaminated accessory drive belt
-
Damaged or contaminated pulley(s)
-
Incorrect accessory drive belt
-
Incorrect fitment of the accessory drive belt
-
Generator
-
Air conditioning (A/C) compressor
-
Pulley(s)
-
Loose hardware
|
-
If an obvious cause for an observed or reported concern is
found, correct the cause (if possible) before proceeding to the next
step.
Accessory Drive Belt Concerns
NOTICE:
Do not lubricate the accessory drive belt as potential
damage to the accessory drive belt material construction may occur.
Cracking
Accessory
drive belts are made from rubber which hardens with time and can
develop cracks. As the accessory drive belt runs on the back of some of
the pulleys, the cracks are opened up. Small cracks are not considered
to be a failure of the accessory drive belt. Only if the crack is deep
enough to reach the bottom of the groove to expose the cord or any
chunks are found to be missing from the accessory drive belt, is the
accessory drive belt condition considered to be unacceptable.
-
Check the accessory drive belt for cracks. If the damage
exceeds the acceptable limit, install a new accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
Chunking
Chunking
describes the condition where long lengths of rubber become detached
from the ribs of the accessory drive belt. This is considered to be a
failure of the accessory drive belt.
-
Check the accessory drive belt for damage. If any chunks are
found to be missing, install a new accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
Pilling
Pilling
is dust that forms in between the ribs of the accessory drive belt from
rubber that is worn off the accessory drive belt when it is new. There
may also be loose particles left on the accessory drive belt during the
manufacturing process. These are worn off and form into small balls of
rubber that then get trapped in the grooves of the accessory drive belt.
This condition will usually clear itself within 4800 km - 8000 km (3000
miles - 5000 miles) of normal driving.
-
Check the accessory drive belt for pilling. The condition of
the accessory drive belt should be compared against the illustration.
-
Small scattered pills. Not considered a concern. No action required.
-
Small scattered pills. Not considered a concern. No action required.
-
Longer pills up to 50% of the rib height. Possible noise
concern. INSTALL a new accessory drive belt if noise is apparent.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
Longer pills up to 50% of the rib height. Possible noise
concern. INSTALL a new accessory drive belt if noise is apparent.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
Incorrect fitment
Accessory
drive belt noise can be generated by the accessory drive belt being
incorrectly fitted on the pulley as shown in the following illustration.
Make sure that all the V grooves on the accessory drive belt contact
correctly with the pulley.
-
If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart
Symptom |
Possible Sources |
Action |
- Accessory drive belt noise
|
|
- Use a stethoscope or other listening device to determine the source of the noise. INSTALL new components as necessary.
|
|
- Accessory drive belt incorrectly installed.
|
- CHECK the accessory drive belt is correctly installed in the pulley grooves. INSTALL a new accessory drive belt as necessary.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
|
|
|
- CHECK the pulley(s) for damage, freedom of rotation, stone entrapment and alignment. INSTALL new components as necessary.
|
|
- Lubricant or other contamination.
|
- CHECK the accessory drive belt for contamination or damage.
RECTIFY the source of the leak and INSTALL a new accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
|
- NOTE:
Chirp is defined as a twittering noise, often intermittent
- Accessory drive belt chirp
|
- Pulley misalignment (usually evident at idle).
|
- CHECK that the accessory drive belt is running centrally on the flat pulleys.
- CHECK the pulleys for excessive end float and bent flanges.
- With the engine running at idle, use a stethoscope to identify the source of the noise. INSTALL new components as necessary.
|
- NOTE:
Rattle is defined as a metallic knocking noise
- Accessory drive belt rattle
|
- Loose components or hardware.
|
- CHECK the components or hardware for correct installation and tighten as necessary.
|
Component Tests
Accessory Drive Belt Tensioner - Static Check
The accessory drive belt tensioner may be checked statically as follows:
-
Inspect the area surrounding the accessory drive belt
tensioner for lubricant or other contamination. Rectify any leaks before
installing a new accessory drive belt tensioner. If the accessory drive
belt tensioner is contaminated, do not attempt to clean it as the
damping mechanism inside may be damaged. INSTALL a new accessory drive
belt tensioner as necessary.
REFER to: Accessory Drive Belt Tensioner (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
Detach the accessory drive belt in the area of the accessory drive belt tensioner.
-
NOTE:
The accessory drive belt tensioner has a damping
feature, which is usually a friction device, therefore some friction
within the system is normal.
Using the correct tool, move the accessory drive belt
tensioner from its relaxed position through its full stroke and back to
the relaxed position to make sure there is no excessive stick, grab or
bind, and to make sure there is tension on the accessory drive belt
tensioner spring.
-
Rotate the accessory drive belt tensioner pulley and
check for damage, freedom of rotation and alignment. INSTALL a new
accessory drive belt tensioner as necessary.
REFER to: Accessory Drive Belt Tensioner (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
If the accessory drive belt tensioner meets the above
criteria, proceed to test the accessory drive belt tensioner
dynamically. If the accessory drive belt tensioner does not meet the
above criteria, INSTALL a new accessory drive belt tensioner.
REFER to: Accessory Drive Belt Tensioner (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
Accessory Drive Belt Tensioner - Dynamic Check
The accessory drive belt tensioner may be checked dynamically as follows:
-
With the engine running, observe the accessory drive
belt tensioner movement. The accessory drive belt tensioner should move
(respond) when the engine is accelerated rapidly or when the A/C clutch
cycles ON and OFF (the degree of movement can be up to 4 mm). If the
accessory drive belt tensioner movement is not constant without engine
acceleration or A/C clutch cycling, a pulley or shaft is possibly bent,
out of round, or the damping mechanism inside the accessory drive belt
tensioner may be damaged. INSTALL a new accessory drive belt tensioner
as necessary.
REFER to: Accessory Drive Belt Tensioner (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
-
Excessive accessory drive belt rideout (uneven depth of
grooves in the accessory drive belt) may cause excessive accessory drive
belt tensioner movement. Check the condition by installing a new
accessory drive belt.
REFER to: Accessory Drive Belt (303-05A Accessory Drive - 3.0L EcoBoost, Removal and Installation).
Removal
NOTICE:
Under no circumstances should the accessory drive belt,
tensioner or pulleys be lubricated as potential damage to the belt
material and tensioner damping mechanism will occur...
Other information:
DISASSEMBLY
NOTICE:
The RH and LH pistons are similar in appearance but differ
in design specifications. The pistons must be installed in the correct
cylinder bank or serious damage to the engine will occur.
Remove and discard the piston rings...
Removal
NOTICE:
Activate the parking brake.
NOTE:
Make sure the vehicle powertrain is powered off.
NOTE:
Removal steps in this procedure may contain installation details.
Remove the screw cap cover.
Disconnect the electrical connector...