Check for Thermal Overload: Notes

WARNING: This page is about a different car, the 2011 Chevrolet Cruze. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: These quick information shall help to carry out a correct diagnosis in case of a customer complaint.

Through friction of clutch plate on the friction surface of the dual mass flywheel temperatures up to 200 °C can arise during normal driving. At sliding clutch or through operating errors much higher temperatures can arise. These temperatures must not cause mandatory a reduced lifetime of the dual mass flywheel.

Possible indications for a high thermal load are:

Tarnish (bluish) as well as local hotspots on friction surface
Tarnish (bluish) near of mounting area and riveting area of clutch

If all other checkable features are well, the dual mass flywheel can stay in the vehicle.

Possible indications for a too high thermal load are:

Cracks
Fusion zones on friction surface (material smear)
Scores in friction surface (for example through clutch lining riveting at destroyed or worn clutch plate)
Tarnish (bluish) which reaches up to bearing area of dual mass flywheel
Bluish discoloration of locating pins (3 locating pins in outer zone of dual mass flywheel)

In these cases the dual mass flywheel has to be replaced.

Fig 1: Overview Dual Mass Flywheel

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Bearing Area
2	Mounting Area Pressure Plate
3	Locating Pins
4	Friction Surface
5	Riveting Area

Fig 2: Exploded View Dual Mass Flywheel with Additional Mass

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Secondary Flywheel Mass
2	Additional Mass, Coupled with Cover and Pulse-Generator Ring
3	Flange
4	Primary Flywheel Mass with Bowed Springs and Plain Bearing/Bearing Bolt
5	Toothed Ring