My clutch is toast

[THOR]

:(
Well, I got two seasons outta my centerforce DF clutch. One with the original numbers matching motor and one with the SD Performance Mill.
Seems bunk that the clutch is already toasted, only about 2K miles on it.
I roasted 'em a lot though :twisted: and I did many a multi gear burnout. Hahaha :wink: . I read a few posts on PY forums about prematurely wearing CF dual friction clutches including at least one instance of a guy sending his back to the manufacturer for a replacement. Should I have gotten more life outta this thing?

[Mark B]

I hope you don't mind a response from a "newbie" and this doesn't answer your question but..... If they still make them, I had a Velvetouch metallic clutch last through 3 GTO's back in the early eightys, I was going through an organic clutch about once a month before that. I did have to replace the flywheel though on the third Goat, it wore out too far to surface. If they still make them you might look into one. The first car I used it on was a Salmon color 64 Hardtop that I dropped a 70 HO 455 into, I only had a 10.5" 389 flywheel, but they built an 11" clutch to fit using Chrysler pressure plate parts. I wish I still had that car :cry: or for that matter any one of the many GTO's I had.

Edited to add that 455 now sits in a friends red 68 Firebird, and it still screams! I'm sending him to SD after reading about them here, he has a pan leaking problem he can't seem to fix, and I think they might solve his problem.

[theJUDGE]

Thor,

I question whether you actually went through your clutch already.
Have you adjusted the linkage as you put the miles on the new drivetrain?

If the linkage has not been adjusted since day one, your clutch is probably ok.

[THOR]

Thanks for the replies Mark B and Mark D. Yes, I've adjusted this clutch at least four times and perhaps there was a fifth time in there. 2x at least with the new mill. There is simply no more adjustment left in the system and the thing's down to the rivets baby. Took tranny and driveshaft out last night to look at it. There's an unusual wear pattern on the flywheel which is still on the car...a groove near the inner part of the flywheel. It may have been wearing or "clamping" more at that part of the flywheel. I'll have to look again at the pressure plate, it was late when I looked at it.

I wonder about another type of really heavy duty clutch. I see from a post on PY forums that some folks recommend Hays or Ram brand clutches. Any others with good experience with any of these? Thanks

[Brandon]

Hey Thor,

I'm curious - do you have the 10.4" or 11" clutch?

Was it slipping very much?

[THOR]

10.4 but am considering an 11 inch one now.
Looking at RAM, ZOOM Kevlar, VelvetTouch clutches now at this point.
RAM clutches can be rebuilt but not sure 'bout the others. Thanx

[triple66]

Be careful of the throw-out bearing you install. Some companies sell one that is too long. The bearing rests against the transmission case and does not release the pressure plate completely. The effect is like you were riding the clutch all the time. The is especially evident with the centerforce design, since they need to expand more with RPM. The centerforce guys recommend over an inch of free play at the top of the pedal to allow for expansion.

[theJUDGE]

Well I believe you now Thor.

Hmmnn, talk about premature failure...

Dan is correct, I wonder how tight your pedal was. I have the same clutch in my 70 & although I only have 500 miles on the rebuild, the clutch indeed has play at the top.

I did not want any more freakin' bearing/throwout issues.

Let us know- TR2004 is fast approaching, I can taste the Pilot Butte..... 8)

[THOR]

Dan and Mark.l..Thanks guys, I'll be scoping out the throwout bearing length issue when the new clutch goes in. The throwout bearing was replaced at the same time the DF unit went in. The DF is being sent to centerforce for eval and a new ram clutch is on the way http://www.ramclutches.com/. I look forward to maximum CLAMPAGE :twisted:

[triple66]

There is a post about troubles with the DF clutches on the PY forum under race drivelines. I can't get the thread to copy here :(

[THOR]

Thx for the info guys. Next questions--
I told a guy about my prematurely worn clutch and he told me I may want to look into balancing the entire clutch assemby and pressure plate :? ??
What the ....? So obviously I've never heard of this procedure. Has anybody else?
I plan on having the flywheel resurfaced here soon also...where do I bring that either in Seattle or on Eastside..Any suggestions?

[REED_RACING]

Call Kirkland Auto parts, J.P. and I have had a lot of things done at there machine shop, been happy so far. Thor who pulled your clutch out of your car?

[THOR]

Thanks for the info on Kirkland Auto Parts. My friend Dave and I pulled the clutch out after observing that there was NO adjustment left in it at all.

Can anybody comment on the balancing question?

It now looks like I may be going with a new aftermarket flywheel as well, we'll see.

I can't wait for better weather and to drive this sucka !! :twisted: :twisted:

[triple66]

All right, I am willing to look stupid and admit that I have never heard of clutch balancing. I have heard of externally balanced motors using non-symmetric weighting on a flywheel. That would require rebalancing the flywheel if you went to an internally balanced motor.

[THOR]

OK, here is the latest in my quest for sub 2.0 second 60 footers. In some cases, I have heard, the rotating assembly of a high performance motor is balanced with the flywheel, clutch disk, harmonic balancer all installed. Still not sure how they do that. Clutch disk balancing is Overkill for my application but here's what I'm doing.... It turns out that my new badarse Ram clutch is best used with a billet flywheel. So, I go out and get a Hays billet flywheel.
Hmmm, having a billet flywheel could be a safety issue, so better consider getting a scattershield. Enter Pontiac Shack with just the ticket plus a block plate, Stef thanks for setting me up with that and at a good broham price. Now I have to either zero balance or match balance the flywheel to the rotating assy. depending on how the sucka was originally done. I'm checking on that now and then I"m moving forward. Literally. I hope :wink: Oh well, at least I don't have any stall converter to worry about. I love 4 Speeds !!

[theJUDGE]

I got to hand it to you Thor:

You are the best I know of when it comes to research.
Lock you in a closet with a couple books on how to fly & you could go lift off a 747 at Sea-Tac, bring her to a 34,000 ft cruise & open up a longneck.

You go brother, get that Silver Bullet ready for TR2004. 8)

[THOR]

As long as it has a 4 speed, I'm there :wink:

[THOR]

I talked to the folks at Centerforce about the clutch that I sent back to them. They say that they think oil contamination caused the pressure plate side of the clutch to get hotter than hell and to sort of glaze up and cause a bunch of slippage, further wearing this sucker out. I said, in a polite way, hey how's about getting me a new clutch at no charge?! They said, Hmmm, no can do but for $150 they'll send me a new one. Should I do this and keep it for a spare?

[1PROGTO]

What type of rear main seal are you using???

I had a clutch go from these symptoms many moons ago...1985 to be exact (Thanks for the help JP). I think the new main seals by BOP are the way to go from what I've heard. I assume Dave put the newer seal in when motor was built. Ohtherwise you might have the old standby- the leaky rope seal. If you find out why it got contaminated, should solve the problem and get the new clutch.

Just my 2 cents...............

[THOR]

This clutch was put in while I had the original motor in the car, That must've been the leaker.
The rear main on the new SD mill is just fine, was looking at it just a little while ago after removing flywheel

[bendgoatracer]

Just a little advice about balancing,I have always balanced my flywheel and cluch,but also important is the drive shaft.Send it with the imput shaft and remove the yoke from the rear end so it cn be balanced together,you wont believe the difference!!!!!

[THOR]

Hi Kelly, I always heed advice from esteemed members of the 150 mph club :)
How is the flywheel balanced with the clutch?
Also, are you saying that the muncie tranny's input shaft can be balanced with the driveshaft? If so, how is that done?
I'm practically walking out the door with my flywheel to have it balanced.
My driveshaft has been custom made and balanced. My M22 was rebuilt by one of the best guys around, Bill Erickson. I probably wont' be able to swing all of this but I would like to learn more and perhaps other Legends members could benefit from learning more on this. Thanks, Thor