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Is this pressure plate warped? And do I need a new one?

joshuaho96
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joshuaho96 Veteran

joshuaho96

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IMG_7793.thumb.jpeg.c44e98c04e6995fa240dfb90b815f59b.jpegIMG_7792.thumb.jpeg.c5d5af3bf15bdbd776e78a8896c411b8.jpeg

Pretty simple question. I was about to put the transmission back in and thought I pretty much had it lined up when I noticed it seems like the pressure plate isn't flat. I was pretty careful when undoing the bolts both during initial disassembly for cleaning and when torquing them up for installation so this is pretty discouraging. I'm not sure if I accidentally bumped the pressure plate with the input shaft and bent it somehow or if it just showed up this way. Is it possible that there's just something obvious I'm not doing correctly? I'm pretty sure I was extremely careful to make sure the friction discs were seated correctly in the hub, everything lined up, flywheel torqued according to sequence, the little springs all sitting correctly in their seats, etc. 

What's the play here? Do I jump straight to a new pressure plate?

joshuaho96 Veteran

joshuaho96

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8 hours ago, GTSBoy said:

I was going to say, "What am I looking at?"....then I saw it.

Um.... dismantle and have a look? I've not seen that before. Looks broken.

The instructions mention making sure the pressure plate is even/flat but doesn't really mention the possible causes of the pressure plate being warped like this.

joshuaho96 Veteran

joshuaho96

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24 minutes ago, MBS206 said:

Normally fingers bent or broken will cause the above.

Has this pressure plate been used before? Was the gearbox left hanging from the clutch while removing the gearbox?

This is brand new. It's possible the input shaft hung up on the pressure plate while trying to wrestle the transmission into position, I wasn't up at the front of the bellhousing to monitor exactly what happened. 

joshuaho96 Veteran

joshuaho96

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2 hours ago, r32-25t said:

Looks stuffed and I’d say it’s an installation error, better grab that wallet out 

Took it apart and somehow when everything is in pieces everything looks fine. Everything looks flat and true. Pressure plate is no longer warped. 

joshuaho96 Veteran

joshuaho96

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1 hour ago, r32-25t said:

What about after you put it back together again?

Miraculously warps again despite every possible method of trying to ensure even torque on the bolts. I'm very tempted to blame the pressure plate at this point. Everything else as far as I can tell does not have any runout issues. I double-checked to make sure the friction discs are oriented correctly and the hub is properly seated on the friction discs.

MBS206 Grand Master

MBS206

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Without better pictures, it won't be possible for anyone to work it out further than we have.

 

Start measuring, EVERYTHING.

Thickness of flywheel, and all around it. You want to know is if everything parallel.

If from the face of the pressure plate (that bolts to the flywheel) if it is parallel to the pressure plate face, then something is NOT parallel or equal elsewhere. Or you've bent the shit out of the fingers in the pressure plate.

joshuaho96 Veteran

joshuaho96

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12 hours ago, MBS206 said:

Without better pictures, it won't be possible for anyone to work it out further than we have.

 

Start measuring, EVERYTHING.

Thickness of flywheel, and all around it. You want to know is if everything parallel.

If from the face of the pressure plate (that bolts to the flywheel) if it is parallel to the pressure plate face, then something is NOT parallel or equal elsewhere. Or you've bent the shit out of the fingers in the pressure plate.

It was simpler than that. Few things going on. One is that I hate plastic clutch alignment tools. Anybody who reads this in the future and is considering one, don't. Even for 3 USD it's not worth it. Mine left plastic shreds all over the inside of the clutch hub. Now I need a proper steel one and to re-grease the hub splines very carefully without leaving any excess that could go into the friction disk or anywhere else unintended.

The second is that I'm bad at reading directions. There is a step in the instruction manual that tells you to put in the 3 M6 bolts BEFORE you attempt to put the clutch onto the flywheel which has been bolted to the crank. You should tighten them slowly and evenly in half turn increments so the springs all compress evenly. Once hand tight back it off until the friction disk can move around between the midplate and the pressure plate. Otherwise the hub won't be able to move properly to line up everything.

The last point which is possibly the most important and is not mentioned in the manual or anywhere at all is that the friction disks are actually not symmetrical. There is a very, very subtle asymmetry to the fingers where they mesh with the hub. These fingers need to be pointing towards the midplate. This helps to make sure the friction disks stay engaged with the hub. Otherwise there is a distinct risk they pop up and out of the hub while you assemble, leading to the warped pressure plate I posted initially.

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luke gtr Grand Master

luke gtr

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Plastic dummy shafts are a fantastic alignment tool. 

WHEN USED CORRECTLY. 

This sounds more like installer error.

I've never had issue with a plastic dummy shaft. Never had any plastic come off one. 

But, glad you redid everything and found your issue.

joshuaho96 Veteran

joshuaho96

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On 10/18/2024 at 3:39 PM, luke gtr said:

Plastic dummy shafts are a fantastic alignment tool. 

WHEN USED CORRECTLY. 

This sounds more like installer error.

I've never had issue with a plastic dummy shaft. Never had any plastic come off one. 

But, glad you redid everything and found your issue.

I'm pretty sure it's just this specific Dorman one. I checked it with the hub by itself and even then it was already shedding plastic. It's only once I ran into all these issues with assembling the clutch that I decided to be skeptical of the plastic alignment tool as well and found it to have a notable amount of slop as the clutch is heavy enough to allow the plastic to bend. 

joshuaho96 Veteran

joshuaho96

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16 minutes ago, luke gtr said:

Coud be the brand.

Have never had problems with the shafts I've used in Australia. 

Even the cheap ones.

Probably yes. I think I could make it work but I'd rather not chance it. I've been having to ask friends for help because the transmission is just that heavy and for the price of ~30 USD I can get the OS Giken one in soon which should guarantee that clutch alignment won't prevent the transmission from seating properly.

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