defective 'new' flywheel...? Help please.?
 

Today I picked up a new Luk DMFW and was planning to take it to get it balanced as an assembly along with the new Sachs pressure plate.

After removing the old one (for comparison purposes), first I noticed that the old one was very stiff and hardly moved between 2-3 mm...

However, the big surprise was the 'new one' because it has too much free play between the left and right limits (before it starts to provide resistance).

If you position the top of the flywheel all the way to the left side of the free play (before offering any resistance), you can then move it all the way to the right about 15mm, before the tension starts to build again to the right.

In other words, you have between 15 to 20mm of play from one side to the other and at each end of the free play you can push the top (with spring tension about 5mm) before returns to that side of the free play.

This does not seem right however, this is the very first time that I hold a DMFW on my hands, is this normal..?

Any comments will be greatly appreciated before I call the store where I bought the new Luk to complain...

Thank you in advance for your comments.
Gilles

Porsche Tech Bulletin 8/02 1360: "Check the dual-mass flywheel by twisting it approximately 15mm to both the left and the right, checking to make sure that it returns to its approximate starting position. If the flywheel can be twisted beyond about 15mm with no noticeable increase in spring force or if it cannot be twisted at all, then it probably needs replacement."

twisting arc
 

Hello JFP,

There are supposed to be No free play when you twisting from the left to the right, am I correct?

Perhaps if I had someone helping me by holding the new flywheel, IT MAY have gone the 15mm to the left but then when you tried twisting to the right, first you go through 15-20mm of free play Before hou start feeling pressure (for 5mm+) that I was able to accomplish by myself...

The issue that concerns me the most, is the fact that the flywheel has the 15-20mm of play between (where) you can twist it to the left or to the right.

Is this extra play in between normal..?

Thank you in advance for your comments!
Regards, Gilles

We normally test flywheels while still bolted to the crank in the car. We insert a flywheel locking tool the grabs the flywheel by the starter teeth, immobilizing the outer mass and then twisting the center mass to check for rotation and return. Held this way, the center does not move without effort, and there should be no slack or looseness.