Clutch Pedal Return

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LaDemon

LaDemon

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There is a much longer story behind this question but, my clutch pedal doesn’t return all the way to the top when I take my foot off. Stopping about 1” from top. Everything else seems to be working properly and I have about an 1/8” gap between the throw out bearing and the pressure plate fingers. Also there’s a wire clip or something on the front top of the clutch pedal arm that is just swinging in the breeze. Does that have anything to do with the issue. Clip is in the picture at the end of the screwdriver.
IMG_9941.jpeg
 
Your picture may not be good enough to show the OC spring.
Anyway, I believe it works such as this.......
The over center spring is what returns the pedal to the stock up stop once the pedal is past the over center position. It also assists your leg when pushing the pedal to the floor with a B&B 3 finger pressure plate.
It works in both directions.
If your over center spring has been removed intentionally, you likely have a diaphragm type pressure plate installed as opposed to a B&B 3 finger pressure plate.
Most diaphragm pressure plates require the spring to be removed as they do not return the pedal back to the over center position of the pedal as the spring is too strong. Leaving it in can cause undue pressure on the diaphragm pressure plate fingers, possibly causing clutch slippage.
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This is the new clutch I just put in. Are you telling me that I need to remove the OC spring to make everything work properly?

IMG_9852.jpeg
 
When you remove the spring, the pedal will still not fully return but it won't stick to the floor anymore. If you want it all the way up then you need to fashion a return spring to lift the pedal. As said the geometry of the over center spring works both ways so you cant use those points as a return spring. I used a heavy spring and turn buckle to make one
 
dano said:
When you remove the spring, the pedal will still not fully return but it won't stick to the floor anymore. If you want it all the way up then you need to fashion a return spring to lift the pedal. As said the geometry of the over center spring works both ways so you cant use those points as a return spring. I used a heavy spring and turn buckle to make one
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It doesn’t stick to the floor now. I’ll remove the OC spring, adjust and see where that leaves me.
 
When using a diaphragm pressure plate on a Mopar, you must remove the over center spring. A diaphragm pressure plate is a General Motors thing, a Borg & Beck pressure plate is a Mopar thing.
 
I’m not interested in starting a huge debate but I would really like to know why the OC spring has to be removed? I don’t have any drivability issues and the throw out bearing is not riding on the diaphragm pressure plate fingers. The clutch pedal just doesn’t come up all the way by itself when I take my foot off. I can bring it up if I lift on the underside with my toe. What am I missing here?
 
LaDemon said:
I’m not interested in starting a huge debate but I would really like to know why the OC spring has to be removed? I don’t have any drivability issues and the throw out bearing is not riding on the diaphragm pressure plate fingers. The clutch pedal just doesn’t come up all the way by itself when I take my foot off. I can bring it up if I lift on the underside with my toe. What am I missing here?
Click to expand...


You remove it because you can’t use it.

You have done several things.

You have changed the ratios between the pedal, the linkage and the clutch fork.

As a general rule, that pressure plate has less base pressure than what the car came with.

The OC spring works both ways as stated above. It helps reduce pedal effort when you push the pedal and it helps return the pedal.

You can have this issue even with a B&B cover if you get the base pressure below about 2800 pounds.

Take the OC off. You still need a return spring that hooks to the clutch fork on one end and to a tab or something on the other end that is bolted to the block or something.

That spring is what returns the pedal to the top.

I have seen some erroneous pictures of that return spring being hooked to the clutch fork on one end and the bell crank (Z bar if that’s what you call it) on the other end.

That is wrong. I’ve seen it multiple times. Do not hook the spring to the bell crank. It needs to go from the clutch fork to a fixed location that isn’t the bell crank.
 
LaDemon said:
.........I can bring it up if I lift on the underside with my toe. What am I missing here?
Click to expand...
At a certain point of pedal upward travel the OC spring should be pulling the pedal up to the stop ABRUPTLY.

Is this the case when you meet that point pulling it with your toe?
 
LaDemon said:
Also there’s a wire clip or something on the front top of the clutch pedal arm that is just swinging in the breeze. Does that have anything to do with the issue. Clip is in the picture at the end of the screwdriver
Click to expand...
I don't think anyone answered that - it's part of the clutch safety switch and has nothing to do with your clutch pedal returning.

The other part is hard to find and expensive. This shows the whole thing
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"MY" solution would be to replace that diaphragm with a Borg and Beck as it was designed to have. Then you won't have to fuss with anything else but getting the clutch free travel right.
 
If your clutch operates without any issues, your good. Your pedal doesn't need to come up level with the brake pedal, 2 of mine don't. If you ever have a problem with your pedal sticking to the floor, then remove the overcenter spring. Few cars are ever the same when it comes clutches, 3-finger or diaphragm.
 
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