I just purchassed a 90 C2 Cab about 2 months ago thats in near mint condition with 24,000 miles. the only nonmaintance work that was done was the addition of the breather hose from distributor recall. I have no records of the duell mass flywheel being repaired I do have a very small amount of what I'll call dripage from the heads but not enough to to call a drip. My question is what is the actually problem with the flywheel that I have read about and how do I knopw if its good or bad? The car runs like new and I'm not sure what the problem is or what it takes to repair? Or what happens if I don't replace it?

p.s. thi9s is a great fourm andI have learned alot about this great car. <img src="confused.gif" border="0">

 

If the car is running fine, don't worry. I have 103,500 miles on the original DMF with no problem. I think the problem with them may be overblown. Someone else will probably be able to chime in and tell you what the signs are that your flywheel needs to be replaced. Barring those, don't worry about it though.

 

Some of the Freudenburg DMFs failed early on, and they are apparently still failing at a somewhat higher rate than the LUK DMF that replaced them in May 1992. If you're like me and worry about such things (I just can't help myself), read Ade's post of 8/01/02 and Hampton's post of 6/19/02 on this forum. According to them, the DMF seems to self-distruct all at once, sounding like bolts being shaken in a metal pail. Ade said he heard a subtle "tinkling" noise and the clutch was starting to "judder" for a while before the failure. Ade's went at 38k miles, and Hampton's at 40k miles. On the other hand, Mike's (subsequent post above) has gone over 100k miles, so you just never know when or if it will go.

My advice is much like Mike's (except I'll still worry about it); just drive it like you owned it. If you eventually need to replace the clutch, you might consider also getting a LUK DMF while you're in there. Congratulations on your new car. Try not to become a worrier like me. ..... Hard isn't it?

 

I made a whole study of this part,

Luk dmf is first fitted on a engine with number 62N07xxx &gt;&gt; from modell year 1993!!!

I have a March 1992 Carrera 2, and has engine number 62N05xxx, and has N O Luk dmf, and I drive around with it on 145.000 km's.

They will break do often make 'race starts' etc.
In normal use they will hold, ask Melissa, she has still the Freudenberg with aprox. the same milage as I have.

Greetings,

Arjan
964 C2 1992 Black

 

DMFs don't always fail catastrophically. When my own failed, it manifested itself as drive-line shudder, in particular, when lugging the engine. It took me a few thousand miles to get around to replacing the DMF, once it was diagnosed as being faulty.

 

Thanks for the additional info, Randall. I assume you had the Freudenburg DMF. At about what milage did it start failing?

 

Hi Jim,

Yup, Freudenberg. It first started making noise at right around 30k miles (just out of warranty, of course), back in 1994. I didn't get around to replacing it until a few thousand miles later. If I wasn't lugging (or close to lugging) the engine, it didn't make any noise. In retrospect, maybe I should have been in a bigger hurry to get it fixed?

Based on a professional recommendation, I replaced the Freudenberg with a LWF that I wound up hating. Took me a better part of a year to figure out what was causing my car to stall (dangerous & embarrassing) and idle wildly with the A/C on (embarrassing). (Keep in mind that back then LWF installations were fairly novel). I eventually convinced Porsche to give me a new LUK DMF (once I learned they were much improved). That LUK was installed at 50k miles, and is still running fine at 116k miles.