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Clutch disengagement issue resolved - ACT clutch issue (Prox, this may apply to you)

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I finally tracked down my disengagement issue with my ACT heavy duty pressure plate and modified street disc clutch. The symptoms were as others experienced, the slow degradation of the disengagement of the clutch.

 

I first thought it my master cylinder so I swapped it out. I then swapped out my slave cylinders. I thought I was not bleeding the lines correctly and bled the bejeezus out of them and even made my own pressure bleeder.

 

I dropped the tranny and swapped out the fork, pivot ball, bearing, and collar. No dice.

 

It was not getting any better. As a matter of fact, it was worsening. The clutch would only partially disengage and getting into reverse and first were getting harder and harder.

 

I remembered when I dropped the tranny that I was feeling around on the pressure plate for anything that may be loose. I noticed that the rivets on the face of the pressure plate that hold the diaphgragm spring rings were loose, but thought nothign of it.

 

I called up ACT today and confirmed that those damn rivets were the issue. The diaphragm spring needs those rivets to be tight as it is hend in place by them. All of the rivets are very loose.

 

I bought the clutch last June and eventhough I am out of the warranty period, ACT stated that they would most likely cover it since a failure of this kind should not occur.

 

I hope this helps someone.

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I finally tracked down my disengagement issue with my ACT heavy duty pressure plate and modified street disc clutch. The symptoms were as others experienced, the slow degradation of the disengagement of the clutch.

 

I first thought it my master cylinder so I swapped it out. I then swapped out my slave cylinders. I thought I was not bleeding the lines correctly and bled the bejeezus out of them and even made my own pressure bleeder.

 

I dropped the tranny and swapped out the fork, pivot ball, bearing, and collar. No dice.

 

It was not getting any better. As a matter of fact, it was worsening. The clutch would only partially disengage and getting into reverse and first were getting harder and harder.

 

I remembered when I dropped the tranny that I was feeling around on the pressure plate for anything that may be loose. I noticed that the rivets on the face of the pressure plate that hold the diaphgragm spring rings were loose, but thought nothign of it.

 

I called up ACT today and confirmed that those damn rivets were the issue. The diaphragm spring needs those rivets to be tight as it is hend in place by them. All of the rivets are very loose.

 

I bought the clutch last June and eventhough I am out of the warranty period, ACT stated that they would most likely cover it since a failure of this kind should not occur.

 

I hope this helps someone.

 

Eww... good to know, at least. Good thing they didn't come apart completely.

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Holy crap.

 

Good thing my transmission is out of the car right now!!

 

I will definitely look at this tomorrow morning when its light out!! Im getting ready to install the Z32 transmission *tomorrow* and my new Fidanza aluminum flywheel! the driveshaft finally came in! whoot whoot!

 

 

Thanks for sharing Bo!

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I went ahead and pulled my clutch and pressure plate today.

 

 

I can't believe how loose those rivets are!!

 

My manufacture date is 08-16-05 .. part number N013.. manufacture number is 0069969.

 

I made a video for everyone to watch and take a look at how much it moves.

 

I called ACT and they want me to send in my clutch, pressure plate and throwout bearing. Although it's out of warranty they will determine if there is something they can do.

 

They said it should be about 2 weeks before I ship it to them and have it back in my hands. ANOTHER delay on this damn transmission swap. ugh

 

http://www.youtube.com/watch?v=Fxuih-9aNtc VIDEO

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Resolution - I dropped my pressure plate off at ACT this morning. After they inspected the pressure plate, they repaired it by the afternoon and I was able to pick it up on my way home.

 

The forensic analysis of the failure revealed that the rivet design was to blame. The rivets were hollow compared to the redesigned pressure plate that uses solid rivets. The diameter of the rivets remained the same. The old, hollow rivets actually stretched and necked down, which is why they were loose.

 

ACT handled this issue very professionally. I trust they will do the same for you Prox.

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Again, thanks for the update gentlemen. I'll have to keep an eye out for my clutch, which only sees a few thousand miles a year. Bo, did Act mention anything about being able to trace back manufacturing dates and identifying potential candidate clutches for failure??

 

Not really. I mentioned that my failure should be fairly common place and if they had received other complaints. The individual I spoke to said that he was not aware of this being a systemic issue.

 

Keep in mind that my pressure plate failed with less than 1000 miles on it. Others may have failed after 5000 or 10000 miles. At that time the clutch was swapped out as part of a overhaul, upgrade, etc.

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Welding beads would not help because the rivets stretched. Welding would only hold the rivets in place but it would not address the stretching issue.

 

I can not say whether or not ACT would repair the pressure plate under "warranty". They stated to me that the rivets should not fail. They were obviously aware that their design was deficient otherwise why would they change it.

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ACT called me today and reported that although the clutch/pressure plate is out of warranty they would repair the pressure plate for customer service!!!

 

Not only are they replacing the rivets on the pressure plate, they are also replacing the throwout bearing and upgrading my clutch disc!!!

 

I am very very impressed with the customer service ACT has provided and I have removed the YouTube video.

 

They should be shipping the product out today! I will report when the pressure plate and new product arrives!!

 

Thank you Bo for bringing up the issue and thank you ACT for backing up their products and providing excellent customer service!

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Wow, great post and might be sticky worthy until ACT changes the design. I have the same pressure plate in my car. Fortunately, I will be doing the Z32/Fidanza swap in a month or so and will definitely be inspecting the rivets.

 

Another point. If they were to stretch unevenly all the way around, it might effect the clutch chatter that the ACT clutches are known for. Could it be a related symptom?

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ACT is aware of the issue and has changed all of the rivets from hollow to solid on the new pressure plates. I did not ask how far back this was changed.

 

ACT also has a higher quality clutch disc that ACT now manufactures.. my old clutch disc was from Exedy that was branded with ACT. They are now producing a high performance clutch disc.

 

Everything seems to be sorted out now, it looks like some of the older units *may* be faulty.. but ACT is willing to address the issue and make the customer happy!!

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I finally fired up the car today after ACT fixed my pressure plate. I was waiting for my downpipe to be ceramic coated. The pressure plate functions perfectly. I had forgotten how easy it should be to shift into first and reverse.

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ACT strikes again. I was having the same problem with poor 1st & reverse engagement. I purchased the ACT road race clutch with 6 puck disc from MSA around 2008 - 2010. I have not put allot of miles on the car since installing the clutch (maybe 2.5k or less). At the end of 2015 driving season I started to get poor engagement of 1st & reverse. I thought it was my hydraulic system going. Replacing MC & slave helped a little but problem came back. Installing a longer slave pin helped for a bit then problem came back. I notice that the problem occurred once the car was warmed up & the clutch used for a little bit it would start to have the mentioned engagement problems. Came across this thread on HyrbidZ in my long quest for answers.  Decided I needed to pull the transmission & inspect what was going on. Sure enough loose hollow rivets holding the spring diaphragm to the clutch body. Replaced the clutch & disc with a Centreforce II along with fork, collar & throw out bearing. When can the engineers stop screwing up?

Edited by JohnH

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