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Resurfacing a pressure plate????

Old 08-19-2004, 06:29 PM
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Default Resurfacing a pressure plate????

Can you resurface a pressure plate and is it recommended???
I took my clutch out today cause it was totally gone and there was nothing but metal on the clutch no material... Anyways it screwed up the flywheel pretty bad as well as the pressure plate. The flywheel i know i can resurface but can I resurface a pressure plate???

BTW its a spec3 clutch and pressure plate. new clutch, replacing old clutch, and I was hoping to use my existing pressure plate...
Old 08-19-2004, 08:16 PM
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You cannot resurface the pressure plate. You need a new clutch.
Old 08-19-2004, 08:19 PM
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I have a new clutch and from what i have heard i can resurface a pressure plate I just wanted some input from some ls1tech guys...
Old 08-19-2004, 10:03 PM
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I would not want to resurface a pressure plate. You'll mess with too many clearance issues by doing that and the flywheel I would think. Do what you like, but the best idea would be to replace everything if it's that bad.
Old 08-19-2004, 10:05 PM
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You cannot resurface the pressure plate. The flywheel is the only friction surface that can be resurfaced. If you were to get the pressure plate resurfaced than the space between it and the clutch would allow excess slippage under a heavy load. If they tell you it is possible it is but DO NOT DO IT!!!
Old 08-19-2004, 10:23 PM
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NO!! ABSOLUTELY NOT!! Unless of course, you want to buy a new transmission..
Old 08-21-2004, 11:15 AM
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Take it to a machine / clutch shoppe familiar with resurfacing flywheels & pp's. They'll be able to check thickness on it. More than likely, it can be resurfaced. I love the alarmist replies in here.
Old 08-23-2004, 12:21 AM
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I wouldnt take too much off though. It depends on which PP it is too...the non adjustable ones you have to be more careful with the amount of material removed.
Old 08-23-2004, 10:44 AM
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Originally Posted by jmd
Take it to a machine / clutch shoppe familiar with resurfacing flywheels & pp's. They'll be able to check thickness on it. More than likely, it can be resurfaced. I love the alarmist replies in here.

You would loose clamping force big time if you increase the distance between the pressure plate bolt surface and the friction surface. Besides that, how the hell would they mount it to turn it?
Old 08-23-2004, 05:15 PM
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The guy said he has to take it apart resurface it and then put a shim(s) under the plate it self so that their are no clearance issues...
Old 08-23-2004, 09:51 PM
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The answer is yes it can be redone, but why?
Most manufacturers will tell you if their product can be resurfaced if you call them. ( I have yet to find one that says this is an acceptable practice, and this will also void any warranty you may or may not have!) If you add shims to make up for the differance that is lost by machining, your putting bullets in the gun. Remember that flywheel is spinning how many rpms when you drop the hammer on it? Do you really want to take the chance of injecting something into the equation that can become a potential bullet? What is the grade strength or centrifugal rating of that washer/shim?
Yes, it's not lkely; but why take the chance, and if you decide to anyhow; then at least warn your passengers you poor-boyed the clutch and let them decide if they want to ride with you! We've all done some engineering in our time; but i wouldn't trust this set-up if i was you!
j
Old 08-24-2004, 12:49 AM
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Originally Posted by 5 Liter Eater
You would loose clamping force big time if you increase the distance between the pressure plate bolt surface and the friction surface. Besides that, how the hell would they mount it to turn it?

The amt. of clamping force you lose with any spring type (diaphragm clutch or otherwise) is not sufficient to junk a new pressure plate if it just needs a tiny but surfaced off it. Basically, you lose clamping force when the disc wears; are you going to junk your clutch every 5k miles?

Some? Yes. Big time? Not even.
Old 08-24-2004, 12:51 AM
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Another method of surfacing them includes clamping the pp so its surface is held up above the pp housing.
Old 06-01-2008, 06:31 PM
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Thread digging here -

The clutch on my LS1 04 GTO was slipping, so I would like to reuse my RAM HD pressure plate and install a new RAM HD clutch disc, and have the stock flywheel resurfaced professionally. My pressure plate/flywheel/slave/etc are are all in good shape. Only concern are some tiny rises and discoloration on the pressure plate surface - looks like surface deposits of clutch material. See pics below - I tried to show it in good light but they didn't come out great.

I haven't been able to find a single machinist/transmission shop/parts store/etc. in the Dallas area that will resurface a pressure plate. So, I want to hand-sand the pressure plate surface enough to remove most of the discoloring/dirt/et. al. and bolt it back up. Is there any problem with this? What grit sandpaper/emory cloth, or other method, should be used?

Thanks in advance,
Chilly
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Last edited by Chilly Palmer; 06-01-2008 at 08:02 PM.
Old 10-05-2008, 05:35 PM
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TTT. I found discoloration in my pressure plate, but no major damage. can it be resurfaced?
Old 10-07-2008, 08:17 AM
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Well, i took my pressure plate and flywheel to a clutch shop and had them resurface both of them. We talked a long time about the PP. He said he would try and resurface the PP by taking only a SMALL layer off, and adjusting some of the straps (looked like we had a high spot). He said he took .007" off the pressure plate. It's a SPEC Stage 2, and i just installed it last night so i'm still breaking it in. But I was very pleased with the look of the PP after the shop finished. Here is before and after:

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Old 10-07-2008, 09:16 AM
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Hey Hollo, what did it cost to have the pp resurfaced?
Old 10-07-2008, 02:10 PM
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I hate to tell you this but by adding a shim to the drive strap MAY have cause the casting not to lift? The Drive strap is what keeps the casting against the diaphragm. You may have a release problem now? When you resurface the casting/pressure plate the loss of material needs to be made back up to put the clutch back in to the pressure curve and have the correct release ratio? I have another question for you did the shop that machined the pressure plate mark where the two pieces (casting to hat) came apart? If he didn’t you could have a serious balance problem. Another issue with the LT1 (pull off) pressure plate is the pivot ring likes to come out of the grove causing a release issue…just a few things to check. In my opinion the clutch didn’t look that bad in the first place….I would call SPEC and get their opinion.

Take care,

Will Baty
Centerforce Clutches
Old 05-10-2009, 07:10 PM
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Originally Posted by 5 Liter Eater
You would loose clamping force big time if you increase the distance between the pressure plate bolt surface and the friction surface. Besides that, how the hell would they mount it to turn it?



After reading through this post I can see that there are people who understand machine work measuring in thousandths of an inch and then there are others that wouldn't know a micrometer from a can opener. For all of you that say "you can't do it" I say you need to read and learn more about automotive machine work and automotive mechanics in general before posting. I would also be very interested to hear from Camaro00 SS on explaining exactly how re-surfacing a pressure plate will ruin your transmission? All your resurfacing off the pressure plate is thousandths, not an 1/8".

If you have some heat spots, minor streaking or raised areas where clutch material has adhered to the face of the pressure plate, taking a small amount of material off the pressure plate, less than .010", will not have any significant affect on the clamping force. Like jmd said, its the same as a clutch that is worn a few thousandths over a year or so of driving. The biggest challenge to this is finding a machine shop that can accurately indicate the pressure plate on the machine to be absolutely sure its flat so that they are not taking more off one side of the disc than the other. That would cause the clutch to chatter and the whole effort of getting it done would be worthless. However I'm not sure I would recommend taking the pressure plate apart to resurface it then shimming it in any way to get the tolerance back, its such a small amount you will never know the difference.

The is also another way that is acceptable to fix a pressure plate, considering its a high dollar pressure plate thats worth fixing and that has more excessive wear like from a clutch that was worn down to the rivets and then driven on for a few more miles to get where your going. You can get the flywheel resurfaced normally and resurface the pressure plate until it cleans up. Whatever the amount of material that was taken off the pressure plate, say .018" then can be removed from the outer part of the flywheel where the pressure plate sits. I wouldn't recommend taking any more than .020" ~ .025" thousandths off the pressure plate because it needs the thickness for rigidity and to dissipate the heat. So for example if the pressure plate was resurfaced .018" then there will be an .018" drop step on the outer part of the flywheel. The lower point being where the pressure plate bolts go and the clutch will sit up .018" essentially putting the pressure plate back in the same location as stock, not altering the clamping force or the release ratio.
Old 02-06-2010, 12:24 AM
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does this need to be resurfaced it only has 1500 kms on it it is a spec stage 1. Where can I get a new disk? mine is bent, and I want to get one locally, it will cost over 100.00 in shipping back to spec other wise! Will a Valeo, Ram HD, Centerforce or Sachs disk work with the spec pressure plate?


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