No. 11-14

Service
Technical Information
11/14
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1360
1
Checking Dual-Mass Flywheel (DMF) on Vehicles with PDK (11/14)
Change overview
Model Line:
Version
Date
Change
0
April 24,
2014
First publication
1
September 9,
2020
•
•
•
Structure reworked
Information added under description of grease leaking out
Information added under "Cup spring diaphragm damaged"
Panamera (970)/Panamera (971)
911 Carrera (991)
Boxster (981)
Cayman (981)
Model Year:
As of 2010
Equipment:
Double clutch transmission (PDK)
Concerns:
Dual-mass flywheel (DMF)
Information:
•
•
Checking dual-mass flywheel (DMF) on vehicles with PDK.
Additional information about the technical features of the dual-mass flywheel.
Assessment:
Information
The following illustrations and graphics are shown only as examples for the sake of clarity.
 The actual component can be different to the component shown, depending on the vehicle.
a)
Dual-mass flywheel is installed:
Increase engine speed evenly from idle speed when the vehicle is stationary:
 Do the vibrations get stronger as engine speed increases?
No
YES
 No action required.
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 Remove and check dual-mass flywheel.
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b)
Technical Information
11/14
Dual-mass flywheel is removed:
•
Visual inspection:
A small amount of grease is leaking out:
A small amount of grease is leaking out of the
dual-mass flywheel  Figure 1 and there is a
ring of grease in the clutch housing  Figure
2.
 Replacement of the dual-mass flywheel is
not justified.
Function OK
Grease leaking from the dual-mass flywheel is
function-related and does not result in function
restrictions, noises or vibrations. The grease leak
may be due to vibrations caused by a rough-running
engine, for example.
If a significant amount of grease is leaking out, the
cause of the engine problems must first be detected
and corrected.
 Remove grease and clean the clutch
housing.
A ring of grease as shown in Figure 2 is considered
acceptable and does not justify replacing the
dual-mass flywheel. More dynamic driving can
cause grease to leak out like this. After removing
this excess emerging grease, it is unlikely that
it will happen again. For this reason, we do not
recommend that you install a new part. However,
the dual-mass flywheel must be checked based
on the other inspection criteria listed in this
assessment in order to determine whether it needs
to be replaced.
Figure 1
Figure 2
A large amount of grease is leaking out:
A large amount of grease is leaking out of
the dual-mass flywheel  Figure 3 and there
is a full ring of grease in the clutch housing
 Figure 4 .
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 Replacement of the dual-mass flywheel is
justified.
Function not OK
 Remove grease and clean the clutch
housing.
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Service
Technical Information
11/14
ENU
1360
1
Figure 3
Figure 4
Balancing weight missing:
A balancing weight is missing and only the
bonding points are left  Figure 5 .
 Replacement of the dual-mass flywheel is
justified.
Figure 5
Cup spring diaphragm damaged:
The cup spring diaphragm is damaged
 Figure 6 .
 Replacement of the dual-mass flywheel is
justified.
The costs incurred for this damage must not be
settled under guarantee or warranty.
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Technical Information
11/14
Damage to the cup spring diaphragm occurs as
a result of improper removal of the transmission
(tilting).
 Make sure not to tilt the transmission during
removal.
Figure 6
•
Mechanical check:
Flange can be turned:
The flange must turn torsionally, but must not
turn back automatically.
 Replacement of the dual-mass flywheel is
not justified.
The possible turning angle (clearance angle)
is approx. 2° - 10°  Figure 7 .
Figure 7
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Service
Technical Information
11/14
Flange can be moved:
The flange must move radially/axially
 Figure 8.
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1360
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 Replacement of the dual-mass flywheel is
not justified.
This property is required for the PDK transmission
and is used for compensation in the event of a static
offset between engine and transmission.
Figure 8
References:
 Workshop Manual '136019 Removing and installing flywheel'
Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© 2020 Porsche Cars North America, Inc.
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Sep 9, 2020
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