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***HELP*** 3800 Fiero GT SPEC Problems - Rodney Dickman Parts by mitchjl22
Started on: 08-05-2014 09:01 PM
Replies: 8 (564 views)
Last post by: stickpony on 08-13-2014 10:58 PM
mitchjl22
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Report this Post08-05-2014 09:01 PM Click Here to See the Profile for mitchjl22Click Here to Email mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
I'm leaving to go to Richland, Washington this weekend, and I drove my car to the alignment shop today. When I drove it out and to my house, the clutch felt "Grabby" while the engine was spinning/running. I could almost feel pulsating in the clutch pedal. Upon release of the clutch, its grabby and not smooth. It dumps. It almost feels like I ran out of hydraulic fluid, but I haven't because the reservoir is full.

Is it possible to have the pedal adjusted too far out and push one of the hydraulic slave or master past its bore?

When the engine is not running, I don't really feel anything wrong. I have a brand new Rodney master and slave. Car is a 3800sc from a 2004 GTP. Flywheel is from a camaro machined to .840 or .860 can't exactly remember which. Transmission is a FWD 1990 Beretta with rodney's install kit.

Help, is this a big problem? Is my car going to make it the distance to fierofest? My biggest worry is that the SPEC stage 3 clutch is coming apart like I've seen before on this forum.

-Mitch
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mitchjl22
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Report this Post08-05-2014 10:52 PM Click Here to See the Profile for mitchjl22Click Here to Email mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
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Dennis LaGrua
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Report this Post08-06-2014 09:11 AM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
It is difficult to tell what is going on but I lean towards the fault of the clutch itself. Pulsating or vibration would not be caused by an out of adjustment slave/master cyl. unless it is not fully disengaging the clutch. The range of fork travel can be seen if you look at the clutch arm while an assistant presses on the pedal. If it is not disengaging fully (you can measure the clearance with a feeler gauge). If disengagement is not happening, you might need to bleed the system. It can be tricky to do this but a Mityvac brake bleeder works great.
If you do an online search of other car forums, you will find that Spec clutches have an inconsistent quality and reliability record. Some are very good and some are very bad. The one time that I used a Spec stage 3 clutch we had problems. We spoke with customer service only to be told it is the installers fault. N ot only did the rep not provide any help, he was arrogant, quick to point the finger and played the blame game.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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fieroguru
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Report this Post08-06-2014 11:51 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
If on clutch engagement (like slowly taking off from a stop), the entire car shakes and jerks... that's what the Spec Stage 3 does. Its called clutch chatter and the Spec Stage 3 is notorious for this condition. The Spec Stage 3+ is much, much smoother.

If while pressing/releasing the clutch pedal, you don't feel smooth fairly consistent pressure on the pedal, then the bushings for the throwout bearing cross shaft might be dry and binding. Take the pushrod out and see how much force it takes to move the release arm back and forth.

As for the sound in the video, does it happen with the pedal pressed or with your foot off it? Could be the throwout bearing or could be pressure plate contact to the inside of the transmission (happens more often on 3800 and 4.9 swaps with modified flywheels).

[This message has been edited by fieroguru (edited 08-06-2014).]

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mitchjl22
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Report this Post08-06-2014 11:59 AM Click Here to See the Profile for mitchjl22Click Here to Email mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
I know what the chatter is. I got that handled after driving with the clutch the last 5k miles. It was hard to control at first, but i got used tonit later. But the vibration I feel is in the pedal. Like when it's fully pressed in it pulsates. I am getting full engagement and disengagement. I can park on a hill, drive forward, push the clutch in, and roll back. With the engine off, I can roll with the clutch pushed in.

What exactly happens to spec clutches? By the way the noise in the video happens when you tap the pedal with your foot lightly and it pushes the TOB up against the pressure plate.

-Mitch

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fieroguru
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Report this Post08-06-2014 12:53 PM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by mitchjl22:

I know what the chatter is. I got that handled after driving with the clutch the last 5k miles. It was hard to control at first, but i got used tonit later. But the vibration I feel is in the pedal. Like when it's fully pressed in it pulsates. I am getting full engagement and disengagement. I can park on a hill, drive forward, push the clutch in, and roll back. With the engine off, I can roll with the clutch pushed in.

What exactly happens to spec clutches? By the way the noise in the video happens when you tap the pedal with your foot lightly and it pushes the TOB up against the pressure plate.

-Mitch


There are only 2 common issues with Spec clutches for Fieros. Spline hub installed backwards and springs falling out.

Way back around 2004ish when Spec first started offering clutches for the Fiero, their first batch had the spline hub installed backwards and it would make contact with the throwout bearing sleeve. Those clutches should be long gone by now, and I haven't heard or seen anyone have that issue in several years.

Again, back several years, there was a rash of Spec 3 clutches where the center springs would pop out and spin around in the transmission case.

I have used Spec clutches almost exclusively since 2005 and have used 6 clutches from them since then and have never had either of these two issues (though I know others who have). If you are concerned about the spring issue, they sell solid hub clutches and there isn't much of a difference in drivability between sprung and unsprung Spec clutches.

Your issue does not sound like either of these two issues.

If the pressure plate isn't tightened properly (or becomes loose), then the tips of the clutch fingers will not be even with each other where they touch the throwout bearing. If this happens, then you might be able to feel a slight pulsing through the clutch pedal as the high fingers passed the portion on the throwout bearing where the release lever pushes (outside of these two areas the bearing could pivot some to accommodate the section of fingers being higher). This pulsing would be 2 times per RPM or say 1800 times per minute, so it would be a very quick pulsing.

The uneven fingers (and a slightly sticking release shaft) might be enough for the throwout bearing to not make contact with the fingers after an extended portion of idling. Normally the hydraulic fluid will keep the bearing and fingers in constant contact. If they are not touching, then as you lightly press the clutch, the fingers will slide on the throwout bearing surface to make it spin. But that sliding should stop once the bearing is spinning or there is much pressure on the fingers.

[This message has been edited by fieroguru (edited 08-06-2014).]

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aaronkoch
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Report this Post08-06-2014 06:02 PM Click Here to See the Profile for aaronkochClick Here to Email aaronkochSend a Private Message to aaronkochEdit/Delete MessageReply w/QuoteDirect Link to This Post
You'll make it Mitch!

Just double check the wheel bearings.

Wait'll you hear the awesome neutral rattle on my Getrag (junkyard pull from about 4 years ago).. It's sweet.

See you Friday!

------------------


Build thread for my 88 + 3800NA swap

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mitchjl22
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Report this Post08-12-2014 08:10 PM Click Here to See the Profile for mitchjl22Click Here to Email mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
Well, I made it the 600+ mile round trip to Fierofest and back. I have come to a consensus though.

The Spec supplied TOB must be weak. I asked around at the show and a few people say they've had similar experience with the TOB. Obviously I have no proof of this, but it's just a hunch. I notice also my clutch feels very bad after the car warms up. If the car is cold, the clutch pedal engages and disengages smoothly, after some driving, it feels terrible. I have no idea where to start diagnosing the issue, but I hope I figure it out quick.

thedrue has a FWD getrag, and rodney parts (I think rodney parts), and he has the same issue as me with over extending his clutch pedal re-engages the clutch and makes a terrible noise on the TOB. He made a temporary fix by spacing the master cylinder away from the firewall to cut down on pedal travel. That seems to be what I'll have to do.

-Mitch
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stickpony
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Report this Post08-13-2014 10:58 PM Click Here to See the Profile for stickponyClick Here to visit stickpony's HomePageSend a Private Message to stickponyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by mitchjl22:

Well, I made it the 600+ mile round trip to Fierofest and back. I have come to a consensus though.

The Spec supplied TOB must be weak. I asked around at the show and a few people say they've had similar experience with the TOB. Obviously I have no proof of this, but it's just a hunch. I notice also my clutch feels very bad after the car warms up. If the car is cold, the clutch pedal engages and disengages smoothly, after some driving, it feels terrible. I have no idea where to start diagnosing the issue, but I hope I figure it out quick.

thedrue has a FWD getrag, and rodney parts (I think rodney parts), and he has the same issue as me with over extending his clutch pedal re-engages the clutch and makes a terrible noise on the TOB. He made a temporary fix by spacing the master cylinder away from the firewall to cut down on pedal travel. That seems to be what I'll have to do.

-Mitch



hey Mitch..doesnt Rodney sell an adjustable banjo for the clutch pedal so you can adjust the throw distance? maybe that will prevent you from overextending as well?

also, i totally agree with you on the spec throw out bearings, they are junk. every time ive used one of their clutches, i toss the beafring and buy a GM genuine TOB from ebay or from gmpartsdirect
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