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 Posted: Aug 29, 2021 08:40PM
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Hi Tim, I don't really deal in thoughts and opinions....

However, it was an estimate - based on the movement of the top of my  clutch arm (just above where the return spring attaches).  To be more precise I measured the travel of the slave rod travel.  It was a pretty crude measurement but the rod travels about 1/2 - 9/16th of an inch (the top of the clutch arm obviously moves more..) 

Did you check whether the slave piston is bottoming out as i suggested?

Noting what you have replaced I would make two suggestions before pulling the master (assuming the piston is not bottoming).

Further assumption is that you have checked the bottom clevis ..and the hole in the Clutch cover that it mounts though?

Before removing the master I would pull the clevis pin that connects the master actuating rod to the clutch pedal ..and the associated holes.  PITA job but you'll have to pull that pin anyway before you can remove the master.    

Cheers, Ian

 Posted: Aug 29, 2021 09:31AM
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Thank you one and all.  The hose to the slave, the slave, the upper clevis pin, the clevis brkt, the arm are all new.  The master is old but as I mentioned will be rock hard when pushed, I think indicating no leakage.  

I appreciate the many suggestions.  I was looking for a stroke dimension which would simply indicate a hydraulic issue of which I could check the nuts and maybe determine the next action.  (Nuts are screwed out as far as I can without hitting the wall).  I measured my stroke at 3/8".  Post by 1963SV3 states I need "almost an inch".  Is this correct?  A guess?  A thought/opinion?  I would really appreciate a real number.  If this is correct then it would appear my master is not working as designed (even though it holds pressure) and I would need to remove (oh boy) and rebuild or replace.  As I mentioned the slave is new so the master would be the ONLY item left to check.  Well and maybe the peddle clevis bracket could be worn out but ....

Thank you 

Tim

In the mean time I will reevaluate the comments, double check based on the comments and see if I can determine just what the problem is.  

 Posted: Aug 16, 2021 06:03AM
 Edited:  Aug 16, 2021 06:04AM
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CA
If I recall correctly, the stop-nut and lock-nut were there to prevent excess throw-out movement of the clutch diaphragm. It may have also limited the (properly adjusted) slave cylinder from bottoming out. Engineers do things for a reason. We just aren't sure of it any more. I'm keeping my nuts.

.

"Hang on a minute lads....I've got a great idea."

 Posted: Aug 15, 2021 06:00AM
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CA
Quote:
Originally Posted by AWOODY
In fact throw the two big nuts away you don't need them , haven't run them in over 20 years ! 
Wow, good to hear this! I've spent way too much time contemplating what these nuts do!

 

Cool

 Posted: Aug 15, 2021 12:40AM
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In fact throw the two big nuts away you don't need them , haven't run them in over 20 years ! 

 Posted: Aug 14, 2021 03:14AM
 Edited:  Aug 15, 2021 03:23AM
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CA
One other thing we forgot: Make sure the stop nut and lock nut on the end of the plunger are not too close to the clutch cover. If they bottom out against the clutch cover ("wok"), no amount of pedal action will fully release the clutch. As the clutch plate wears, the gap available for actuation reduces. As Awoody says, they aren't necessary, though they can give an indication of clutch plate wear, if measured accurately.

.

"Hang on a minute lads....I've got a great idea."

 Posted: Aug 13, 2021 09:31PM
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I would suggest 2 immediate investigatory steps....

1.  Peel back the slave rubber so you can see inside.  Have assistant push (and hold) clutch pedal down as far as possible.  Look and see whether the slave piston is reaching the circlip at the outer end of the slave bore??  

2.  Remove the clutch return spring (the one on top of the slave), press the clutch pedal a few times.  Does this make a difference??

IME you need almost an inch of travel at the top end of the clutch arm.  3/8th" is way inadequate...

Cheers, Ian

 Posted: Aug 12, 2021 02:21PM
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CA
Your stroke may turn out to match the spec, but if the end of your stroke bottoms out the slave cylinder - due to worn components between the lever and the clutch pressure plate, the movement may not be enough to pull the pressure plate away far enough to break contact, resulting in clutch drag even with your foot to the floor.
Take the lever off and have a good look at it. Is the pivot hole worn? Is the pivot pin worn? Is the ball on the clutch end worn or broken? If you are up to it remove the shuttle the lever pushes on and check it for wear.

.

"Hang on a minute lads....I've got a great idea."

 Posted: Aug 12, 2021 07:40AM
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Thank you for the info.  All good.  The master is such a problem to remove!  I was thinking if I had the movement of the arm dimension, and my stroke of 3/8" was too short; I could then determine that the brake master is in need of repair and go to work.

Still would like this dimension if possible.

Thanks much.

Tim 

 Posted: Aug 11, 2021 06:58PM
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US
Tim - look at the mechanical as well as the hydraulic component.  As a 65 is what 56 years old when was the last time the Clutch master cylinder was rebuilt or replaced?  Is there any wear in the clevis pin that goes from the clutch pedal to the master cylinder ( or wear on the pedal where the pin goes thru? ) Also check the push rod on the master cylinder - has it become worn (hole oval instead of round ) System has been bled and brake fluid topped up?  Slave new or rebuilt? push rod worn, clevis worn (check both ends of the arm ).  check the end of the arm is the ball worn? plunger worn in the area where ball contacts it.  and adjusted for clutch arm stop?

 Posted: Aug 11, 2021 05:32PM
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Hello.
I am having trouble shifting into 1st thru 4th gear.  The car is a 1965 Austin Cooper S 1275.  I believe I have set the clutch up per the manual.  I start the car in neutral. Starts great.  Clutch pushed to floor.  Shift to 1st.  Can't as gears grind.  I try 2cnd gear  Can't as gears grind.  I am beyond confused.  I have replaced the slave cylinder.  Why?  Just because I had a spare.  No change.  I bolted the slave cylinder to the housing and pushed the clutch peddle.  No movement, which is correct I think, and which means no leaks in the clutch hydraulics as if there was a leak the peddle would slowly go to the floor. 

It just seems the clutch is not moving/stroking far enough.

The clutch stroke just seems to be too short.  I measured the movement of the throughout clutch arm/spring attachment at the spring hole.  I have 3/8" travel.  Can someone check if this is correct?  Should be more?  Is OK?  Any suggestions?  What is the overall length of the slave cylinder push rod?   Maybe my slave push rod is too short.

Thanks for any suggestions/comments

Tim


While the slave cylinder was With the Through out arm