Is this normal ? Sound from clutch pedal

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Mopar92

Mopar92

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maybe I’m just paranoid or I don’t have any driving with an old Mopar 4 speed. This is my first 4 speed, not manual trans vehicle though. I’m getting some
Miles on the Duster so it’s time to let it rip. I did a 5,000 rpm pull in a couple of gears tonight.

73 Duster
New-Ram clutch and throw out from Brewers
New- billet steel flywheel balanced for LA360
A-833
Mild 360 LA

I have about .060-.065 air gap
I have the return spring for the fork
I have a little free play in the pedal/ fingers to throw out bearing.

I noticed sort of a vibration/metallic chatter INSIDE the car around the clutch pedal. Anytime I got up 4,500-5,000 on a pull I could hear a little vibration down there. Almost as if I was riding the clutch a little and connecting the clutch, TO bearing etc. it’s hard to explain but that was strange. It’s odd that there would be that much “connected” to the pedal to transfer any engine vibration through the pedal. It’s not bad but I did notice it. I can’t imagine how there is any seeing as the fork spring is pulling the fork back from the clutch. Maybe I can get some good video/audio while driving it. You don’t hear anything unless you are 4,500+ rpms wot.
 
just try backing off on the adjustment some to see if it clears up before you start worring about anything else
 
You could check that the adjust rod insulator and damper washers are still good under the pedal rod. Also check that the spring washers have good tension against the pedal rod.
Check your clearances from bell crank to everything through the rpm range. IE, is the engine moving and causing a bind somewhere?

4sptechindex_clip_image002.jpg
 
Here’s something strange. I drove the car another 60 Miles today. It doesn’t matter if it’s full throttle, partial, in neutral... when the car is say 3500, if you just tap the free play in the pedal, it’s much stiffer at 2300+. I know it’s hard on the throw out bearing but it’s not like I’m pushing the clutch in enough to slip it. This is just a test. The pedal free play is much stiffer at a higher rpm. You can just rest the weight of your foot on it and when the rpms get to around 2000, your foot will sink down. Then the free play is much easier. Are there centrifugal weights inside these clutches? Without question the free play is there, but a lot stiffer. For sure the engine vibration and harmonics are coming through the clutch pedal at higher rpms because it’s stiff. Until it’s 2000 or so and the free play only takes a pinkie finger to slack. Strange.
 
That is because it's adjusted just a little too tight.The centrifugal force as it increases in RPM causes everything to expand which is why you need more free play .
 
Perfect. That makes sense. I’ve never had a clutch like this before. That’s pretty interesting. I’ll back it off and check my air gap again and run it again. Thanks.
 
I backed the throw out bearing and fork off probably too much. Have a good 2” of free play but I want to eliminate that as the problem. Same thing. The clutch pedal assembly vibrating with the engine is making a metallic noise. Quite aggravating and scary in the sense that somethings not right. Here’s a video of a 3rd gear pull.
 
Same exact gear and pull basically with my foot 1/4” on the pedal to stop the damn harmonics from coming through the pedal. It does have the clutch bump rubber in. I checked.
 
Maybe it's time to pull it all apart and look inside.It wouldn't be the first time defective parts were sold .
 
I wonder if a header pipe is touching the fork-rod or Z-bar.
Is the fork staying in the window and not backing up too far, and touching the bell?
Is that clutch a 3-finger job?
I heard it in the video starting at about 40/45 mph

You know.... it sounds like fingers in the fan right? Check your crank end-play.
It's like the clutch is moving rearwards and hitting something inside the bell, and when you ride the pedal that you are actually pushing the clutch forward away from that item, thus silencing the noise. Just guessing.


I like the sound of your exhaust system.Was that floored?
 
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Sure it's not your signal relay bouncing inside the dash frame?
 
End play in the crank is minimal. All that noise is in the clutch pedal and clutch pedal bushings. Even with 2” freeplay... which is too much ? The free play is for sure more than the free play at idle. Something at exactly 2000 rpms is settling down allowing easy freeplay. The motor isn’t torquing up. We go pro videod the engine. Seems minimal actually. The clutch disc isn’t in backwards either. I dunno what’s going on.
 
AJ/FormS said:
I wonder if a header pipe is touching the fork-rod or Z-bar.
Is the fork staying in the window and not backing up too far, and touching the bell?
Is that clutch a 3-finger job?
I heard it in the video starting at about 40/45 mph

You know.... it sounds like fingers in the fan right? Check your crank end-play.
It's like the clutch is moving rearwards and hitting something inside the bell, and when you ride the pedal that you are actually pushing the clutch forward away from that item, thus silencing the noise. Just guessing.


I like the sound of your exhaust system.Was that floored?
Click to expand...


That’s a magnaflow muffler with Jegs x pipe that was on sale. TTI head pipes cut just a little on one side to mate the exhaust. Exhaust is to the back bumper compliments of my neighbor who owns a nice exhaust shop.

98180476-5B04-4D95-9ECE-F86CC637486F.jpeg
 
Maybe a dumb question, but; You did install the locator spring-wire on the left end of the Z-bar right? and correctly engaged it in the white plastic bearings? In Dave's post,#3, it's called a snap ring.

The over-center spring makes clutching easier as the pedal goes down; and that is normal. For a diaphragm clutch, this spring needs to be removed, which is why I asked about the 3-finger deal which for, if you have one,you leave it in.

BTW I set my clutch departure at .080, and let the freeplay be whatever.This for a DD. But 1 inch of freeplay usually gets you that .080. If the gears clash on the 1-2 shift sometimes that can be traced to not enough freeplay; not always.
After I slick-isized my second and third gears, and started splitting gears with my GVOD,I tightened it up some; quite a bit actually. But I have to adjust it more often. No big deal after I modded the locking system.
 
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AJ/FormS said:
Maybe a dumb question, but; You did install the travel-limiter on the left end of the Z-bar right? and correctly engaged in the white plastic bushings?

The over-center spring makes clutching easier as the pedal goes down; and that is normal. For a diaphragm clutch, this spring needs to be removed, which is why I asked about the 3-finger deal which for, if you have one,you leave it in.
Click to expand...
Sorry I missed that. It’s a borg and beck 3 finger from Brewers. Everything is from them. I still have the over center spring in. I called them today and Dan said he’s never heard of anything like this. Hmmm.

Ps- travel limiter ??
The fork isn’t touching the bell.
Z bar aligned well and is seated in the bushings yes.
 
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AJ/FormS said:
Maybe a dumb question, but; You did install the locator spring-wire on the left end of the Z-bar right? and correctly engaged it in the white plastic bearings? In Dave's post,#3, it's called a snap ring.

The over-center spring makes clutching easier as the pedal goes down; and that is normal. For a diaphragm clutch, this spring needs to be removed, which is why I asked about the 3-finger deal which for, if you have one,you leave it in.

BTW I set my clutch departure at .080, and let the freeplay be whatever.This for a DD. But 1 inch of freeplay usually gets you that .080. If the gears clash on the 1-2 shift sometimes that can be traced to not enough freeplay; not always.
After I slick-isized my second and third gears, and started splitting gears with my GVOD,I tightened it up some; quite a bit actually. But I have to adjust it more often. No big deal after I modded the locking system.
Click to expand...

Left end ? Confused. I inatalled the return spring so it pulls the throw out away From the fingers. Is that what you mean ?
 
Scary. I read his description and I thought I wrote it ! This is what I think I’ve got going on too.
 
I’ll post on the other thread too but I got the car on the lift today. Changed the trans fluid and left the bell a little messy. Sorry. Anyway. I have .055” air gap, 1” pedal play and .260” of throw out bearing clearance. To drive it you need 2.5” of free play to keep it from totally killing the TO bearing. Extremely annoying with the pedal play but it allowed me to diagnose this problem. It’s terrible feeling to drive. Anyway. I’ve got .600” or finger travel. It’s cooked the throw out bearing. Not even sure where to start besides pull it and send it to RAM.
 
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Hang on;
.055 and 2.5 does not compute
this is too much freeplay and not enough departure
I understand why you have it set up like that;
But I don't understand what is going on inside that clutch.
I've never experienced such a thing.
 
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