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Clutch Problems 66 427/425

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Old 03-14-2019, 02:46 PM
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Tcheairs38655
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Default Clutch Problems 66 427/425

I've got a pretty substantial "shudder" in my new (Rhino from Paragon) clutch when trying to ease around into the garage and parking in the 427, so I'm going to tear into it and see what's going on. I've noticed in some posts on this subject that the preference seems to be the the 11" McLeod over the Centerforce. I was just wondering what the differences are. A specific suggestion by part number for an 11" street clutch kit from Jegs or Summit would really be helpful. No racing, just street driving.

My clutch and throwout bearing are new and flywheel was resurfaced as part of the engine rebuild. There are no oil leaks that I can see. One strange thing, my mechanic (we are no longer speaking) has the clutch rod attached all the way forward out on the end of the rod. You can see where it was originally attached near the center of the rod. There aren't even enough threads left to get the forward retaining hex nut on securely. Car goes in and out of gear nicely and shifts without any problem and no shudder as long as the clutch is released in a normal manner and not "ridden". Clutch is fully engaged at about 6" off the floor board firewall. Thanks

Last edited by Tcheairs38655; 03-14-2019 at 05:41 PM.
Old 03-14-2019, 06:59 PM
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DansYellow66
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Tom - I answered your email. The adjustment is not optimum but it's not causing the chatter. I would measure the length of the lower rod as you may be able to substitute a longer one and move the clevis back - but if working OK you may want to leave it alone. As the clutch wears (may be awhile) the adjustment to compensate will move the clevis back. Just about anything else will require pulling the transmission and checking everything like the fork, ball stud, etc.

Under what conditions is it chattering and not chattering?
Old 03-14-2019, 07:44 PM
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dcamick
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Do you feel comfortable with the resurfacing of the flywheel???? That could be the variable that might cause the chattttttttering.............
Old 03-14-2019, 08:01 PM
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Lars did an excellent writeup on proper clutch selection and installation awhile back. We discussed it here only a few months ago..........so search for it.

Appears that incorrect flywheel surfacing, flywheel not flat on the surface, clutch spring (or finger) broken, or clutch face not flat are the primary reasons for shudder. I guess grease on the clutch disc could also be an issue due to careless install.

If you thoroughly read the Lars article and the comments we added you will know what you need to do.

Larry
Old 03-14-2019, 08:43 PM
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Avispa
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It sounds like your clutch is engaging close to the top of pedal travel. Good. Check for a rubber bumper in the pedal bracket. There should held one pointing down from the bracket that stops movement of the pedal flange. If its thin or missing, get a replacement. That will move the pedal upper stop point down, and then require some backward adjustment on the threaded rod.

And flywheel surfacing....it needs to be done on a grinder, not a brake disk lathe. Rough surface from a lathe will make it chatter.

Last edited by Avispa; 03-14-2019 at 08:44 PM.
Old 03-14-2019, 10:16 PM
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GTOguy
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Not clutch related, but your steering shaft looks like it needs to go into the rag joint another half inch at least.
Old 03-14-2019, 11:21 PM
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Powershift
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Originally Posted by GTOguy
Not clutch related, but your steering shaft looks like it needs to go into the rag joint another half inch at least.
Very true..........and a good observation.

Larry
Old 03-15-2019, 05:48 AM
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tbarb
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I think the assembly manual calls for the steering shaft 1/2 way into the rag joint. That being said It's probably got a good inch inside the flange so it looks ok to me.

The suggestion for the rubber stop bumper is something to think about.
Old 03-15-2019, 06:11 AM
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Gavin65
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You state your not speaking to your mechanic , so obviously you have words about this, im going to say the issue is in the re surfacing of the flywheel, did you see what it looked like before it was re surfaced? when i replaced my clutch i replaced the flywheel, i had considered re surfacing it but it looked like the victm of one too many hole shots. what about the piolt bearing , was that replaced as well?
Old 03-15-2019, 08:07 AM
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Tcheairs38655
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Thanks for all of the good ideas...I'll get right on them and report back...I should add that the only time I have the chatter/shudder is when easing around slowly when I need to ride the clutch such as entering the garage or backing into a parking place.

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