Clutch Pedal Adjustment

[bogdonj]

I noticed in Les Andrew's handbook under Transmission section that the clutch pedal s/b adjusted for 1" free pedal travel before clutch engages!! I checked mine and it is about 1/2" when clutch engages!! Could someone tell me what the theory is or why it is important to have at least 1" travel ??? thanks.

[Tom Endy]

The clearance is so that the throw out bearing is not riding the clutch. If it is it won't last long. Regardless of what it is set at, one inch, 3\4", 1\2", the trick is to provide enough clearance to allow the throw out bearing to be pulled back by the little spring hooked between the front of the trans and the throw out bearing carrier.

Remove the cover plate on the bell housing and start the engine to see what the throw out bearing is doing at rest. Good idea to give it a shot of grease while the cover plate is off.

Tom Endy

[John S]

There has to be enough clearance between the release bearing and the pressure plate levers. If there is not enough free travel in the pedal the bearing can contact the levers while the clutch is out, causing it to slip and or causing the bearing to spin constantly and fail.

[Larry Seemann]

Just for clarification: the 1" of free travel is at the top of the pedal before the clutch "disengages", not engages which would be at the bottom of the pedal travel when letting the pedal up to engage the tranny.

[Tom Wesenberg]

As the clutch disc wears, the freeplay gets less, so some guys may elect to go with 1" freeplay so they won't have to get under the car to readjust the clutch quite so soon.

[bogdonj]

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Originally Posted by Tom Endy

The clearance is so that the throw out bearing is not riding the clutch. If it is it won't last long. Regardless of what it is set at, one inch, 3\4", 1\2", the trick is to provide enough clearance to allow the throw out bearing to be pulled back by the little spring hooked between the front of the trans and the throw out bearing carrier.

Remove the cover plate on the bell housing and start the engine to see what the throw out bearing is doing at rest. Good idea to give it a shot of grease while the cover plate is off.

Tom Endy

pulled the inspection plate off and inspected the throw out bearing and at rest it just sits there...doesn't spin. 1/2 inch it starts to spin and engages... but when I let the clutch out it stops and doesn't spin one bit? So this is what I want correct? if it was always spinning then it would wear out faster correct?

[Milton]

The main reason has been covered, that is to allow the clutch to fully engage and allow space for clearance and future wear. After that the aim is for comfort and usability. Nobody likes to hold the friction point with their heel off of the floor and it is hard to speed shift if the pedal has to be depressed to the floor.

[Milton]

Originally Posted by bogdonj

So this is what I want correct? if it was always spinning then it would wear out faster correct?

Yes.

[Tom Wesenberg]

Originally Posted by Milton

The main reason has been covered, that is to allow the clutch to fully engage and allow space for clearance and future wear. After that the aim is for comfort and usability. Nobody likes to hold the friction point with their heel off of the floor and it is hard to speed shift if the pedal has to be depressed to the floor.

Can you speed shift a Model A?

[Milton]

Originally Posted by Tom Wesenberg

Can you speed shift a Model A?

Ohhh yah, that's what I learned on.

The trans in my 31 Fordor seemed invincible. I even dropped a clutch insp plate screw into it and couldn't find it with a magnet. Figured it missed and fell in the dirt, it didn't. The screw was crushed in the second/high slider after it went through the gears and I pried it out and was on my way. That's when Ford tough meant it.

[bobpo]

In response to Milton's posts, I have to admit that I am one of them who HAS TO STAND ON THE CLUTCH PEDAL just so I can get it to shift between gears and if I'm not real careful I will grind the gears. Plus, I don't seem to have any more threads on the adjustment bolt.

Question #1.....Why?

Question #2.....Does the carpet thickness have any influence on the pedal play? (I would thik it does)

Thanks for any input....as usual.

[Tom Endy]

bobpo:

The problem you are experiencing is the adjustment of the fingers of the clutch pressure plate and has nothing to do with the adjustment of the linkage that adjusts the free play of the throw out bearing.

The adjustment of the pressure plate is done with it bolted to the flywheel with the clutch disk sandwiched in between. Each finger is adjusted to a nominal 5\8" distance from the rear surface of the pressure plate.

It sounds like yours needs to be readjusted.

Tom Endy

[Milton]

Originally Posted by bobpo

In response to Milton's posts, I have to admit that I am one of them who HAS TO STAND ON THE CLUTCH PEDAL just so I can get it to shift between gears and if I'm not real careful I will grind the gears. Plus, I don't seem to have any more threads on the adjustment bolt.

Before adressing your questions, a little background info is required. If you are standing on the pedal so the trans will not grind you are wasting your time. They are called crash boxes because of the straight tooth design and lack of a synchromesh mechanism. Do you double clutch when shifting? This is practically a necessity when driving normally. I am not trying to slight your intelligence but I don't know your A driving experience. The average person driving a stick shift just can't grasp how primitive an A trans is, strong but strange. Of course continuously grinding gears will do in the trans over time and the method to avoid grinding, then and now, was to double clutch when shifting. Soooo, do you double clutch?

[bobpo]

Milton,

In answer to your question pertaining to the Double Clutching, I only do that when down-shifting from 3rd to 2nd.

Are you supposed to Double shift starting off from 1st then into 2nd and then 3rd?

That is something I have not learned and yes I am new to operating this Coupe.....

Thanks for your input.

[Milton]

Originally Posted by bobpo

Milton,

In answer to your question pertaining to the Double Clutching, I only do that when down-shifting from 3rd to 2nd.

Are you supposed to Double shift starting off from 1st then into 2nd and then 3rd?

That is something I have not learned and yes I am new to operating this Coupe.....

Thanks for your input.

Well you are in for a driving treat. Yes, you get to double clutch shifting up and shifting down. The methods are different, in that, when upshifting you do not hit the gas as you do when downshifting. Start in low, depress the clutch, go to neutral, release the clutch, slight pause, depress the clutch go to second, release the clutch, and do all over again for high gear. Third gear is a necessity because of the larger ratio change. The reasoning behind double clutching is to syncronize the sliding gear speed to the input/cluster gears. So when upshifting the input is slowed down to match the next gear and when downshifting the input is sped up by tapping the gas to match the previous gear. Furthermore, but not recommended, shifting can be done without the clutch or grinding of gears by matching the engine speed to the car speed.

Once accustomed to this, adjust your clutch for comfort while retaining a minimum of 1" freeplay in the pedal.

All part of the fun of driving an A.

[700rpm]

Originally Posted by bobpo

Milton,

In answer to your question pertaining to the Double Clutching, I only do that when down-shifting from 3rd to 2nd.

Are you supposed to Double shift starting off from 1st then into 2nd and then 3rd?

That is something I have not learned and yes I am new to operating this Coupe.....

Thanks for your input.

I almost always double clutch going up and down. It's a habit I learned from the time when my first A was unrestored and it seemed necessary. It isn't necessary now, but it does make shifting easier sometimes.

[bobpo]

MILTON,

You are one great Teacher. So I should call you "The Professor".

Momma & I took a little drive out here in the country and went to the
Ice Cream place. I decided take my First Lesson in Double Clutching.
I think I deserve a Gold Star as I did not get one grind, going or coming. It was music to my ears. (And Momma's)

Next I found a small amount of gas in the Carb Throat when I shut 'er down. That's obviously where the Gas Fumes are coming from that Momma complains about everytime we go for a ride in it. (I don't run with the air cleaner)

I guess I'll have to figure that one out next.

THANKS AGAIN PROFESSOR MILTON

[Milton]

Thanks, I have certainly been called worse.

About the gas, when you shut off the engine you hear the famous Model A sound "shhh uh shhh." That is the sound of the piston coming up on compression and not getting past TDC. Since the piston doesn't go past TDC it reverses and goes back down. While this is occurring the cylinder that was on intake is also reversed and blows intake air past the jets in reverse creating the puddle in the carb. To alleviate this you can anticipate shutting the engine off and turn off the fuel valve before hand. That way the car runs out of gas or nearly so, less or no gas, less or no fumes.

God I love these cars.

[bobpo]

Milton,

My wife was right, I changed Bogdonj's post by wandering off into Model A'dum. For this Bogdonj, I apologize, I don't even know how I got this going. I'll have to go back over your entire thread and see how I started off on this avenue.

Milton, my question at this point would be; would this scenario you're describing cause her (my wife) to smell fumes the whole time we're cruising or just at 'shut-off' ?

BTW, She says the same thing when we're in the Dunebuggy. (but I think I know where they are coming from in the Buggy).

I've always said, my wife could have put those cute little Canaries out of work in the Mines..................................

P.S. How do you know all this stuff anyway.......????

[kenparker]

In answer to Tom ans Milton's comments about "Can you speed shift a Model A". Sure. But dont expect the tranny to last too long. When you are "Hillclimbing" and are trying to get that Model A powered contraption up the hill in 10 seconds or less, the cost of a messed up transmiion does not matter IF YOU WIN. ken