Clutch adjustment '79
#1
Three Wheelin'
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There's an adjustable push rod that activates the clutch master cylinder. I want my clutch to engage at the beginning of pedal travel, not near the floor. The manual mentions 0.5mm space. Perhaps there is air in the system, but it's not spongy at all. The clutch is NEW.
I'm assuming as long as the throwout bearing isn't spinning, I can adjust the rod as far as I want. No?
I'm assuming as long as the throwout bearing isn't spinning, I can adjust the rod as far as I want. No?
#2
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Gregg,
Page 30-1 (not 30-01) of the manual says that you should adjust the peddle to zero then preload one revolution of the rod. i.e.there should be no freeplay.
Dennis
Page 30-1 (not 30-01) of the manual says that you should adjust the peddle to zero then preload one revolution of the rod. i.e.there should be no freeplay.
Dennis
#3
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Hi Dennis,
My page 30-1 doesn't say that. It says 0.5mm play. Before I posted I did a search and found the same thing that you said about no play plus one turn. But that's still WAY far away from the setting where I feel the pedal should be. I still have to ask the question, can I screw the rod in further as long as the throwout bearing isn't contacted by the forks? Otherwise why would my clutch pedal be all the way to the firewall?
My page 30-1 doesn't say that. It says 0.5mm play. Before I posted I did a search and found the same thing that you said about no play plus one turn. But that's still WAY far away from the setting where I feel the pedal should be. I still have to ask the question, can I screw the rod in further as long as the throwout bearing isn't contacted by the forks? Otherwise why would my clutch pedal be all the way to the firewall?
#4
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Gregg,
You can adjust it in further, but you run a big risk of causing the clutch to slip. Are you sure it is bled properly? Were the new clutch disks spaced properly? My 78 5 speed also requires the peddle be fully depressed but my 931 only requires half the travel. They are both hydraulic so I assume it is the difference in linkage. BTW my page 30-1 is dated 1991.
Dennis
You can adjust it in further, but you run a big risk of causing the clutch to slip. Are you sure it is bled properly? Were the new clutch disks spaced properly? My 78 5 speed also requires the peddle be fully depressed but my 931 only requires half the travel. They are both hydraulic so I assume it is the difference in linkage. BTW my page 30-1 is dated 1991.
Dennis
#5
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I'm NOT sure the clutch is bled. The pedal isn't spongy, but that probably doesn't mean much. I'd sure like to know where the definitive clutch bleeding procedure is. They sure missed out putting it in MY shop manual. I did check for page 30-01, and in my book the only mention of clutch linkage is on 30-1. Oh well, older manual I guess.
I'll do the spacing check. Devek did the install, so it probably was spaced correctly.
I've got the new owner barrage of things to do, and it makes for a never ending source of fun and excitement (like the hissing sound under the dash).
Thanks Dennis
I'll do the spacing check. Devek did the install, so it probably was spaced correctly.
I've got the new owner barrage of things to do, and it makes for a never ending source of fun and excitement (like the hissing sound under the dash).
Thanks Dennis
#6
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Gregg,
One other reason not to excessively preload the clutch is the additional wear on the throwout bearing. If the center section of the bearing is spinning constantly its life will be extremely short.
Dennis
One other reason not to excessively preload the clutch is the additional wear on the throwout bearing. If the center section of the bearing is spinning constantly its life will be extremely short.
Dennis
#7
Three Wheelin'
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I can hear the throwout bearing when it starts to spin. It isn't spinning until the clutch pedal is pushed way down. That's part of my question- As long as the throwout isn't spinning, is it ok to adjust that rod? Wait.....
None of this makes any sense. I mean, why would it seem like I've taken up slack with the adjuster rod if I haven't even touched the throwout with the fork? Hmmmm. I'll go back and look at the book, but in my experience, the clutch fork should only have a nominal return spring force, and the only substantial force should occur once the throwout bearing is encountered. I'm going to do some experimenting and I'll get back.
PS I'm a member now. I guess it doesn't show on my posts yet.
None of this makes any sense. I mean, why would it seem like I've taken up slack with the adjuster rod if I haven't even touched the throwout with the fork? Hmmmm. I'll go back and look at the book, but in my experience, the clutch fork should only have a nominal return spring force, and the only substantial force should occur once the throwout bearing is encountered. I'm going to do some experimenting and I'll get back.
PS I'm a member now. I guess it doesn't show on my posts yet.
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Hey Gregg, did you ever get this figured out? I am interested in pulling the engage a bit more off the floor as well and wondered how you faired.
TIA!
TIA!
#9
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(Pasting this from another thread because there seems to be some confusion about this subject)
Hi
actually I am also not sure about adjusting the clutch. In my driver's manual it says there should be 2.5 mm free play (not specifying where that is measured at). Is that the travel measured at the pedal pad from the rest position until the clutch starts to disengage?
I have also noticed that if there is too much free travel in the clutch pedal there is a tweeting noise during driving which goes away if you depress the clutch pedal slightly, like to leave only about 1 mm (measured at the pedal pad) until the clutch starts to disengage.
Another thing: to lengthen the pushrod why do you remove it from the pedal? I mean you can turn the pushroud without removing it, does that depend on the model year?
Cheers Thomas
Hi
actually I am also not sure about adjusting the clutch. In my driver's manual it says there should be 2.5 mm free play (not specifying where that is measured at). Is that the travel measured at the pedal pad from the rest position until the clutch starts to disengage?
I have also noticed that if there is too much free travel in the clutch pedal there is a tweeting noise during driving which goes away if you depress the clutch pedal slightly, like to leave only about 1 mm (measured at the pedal pad) until the clutch starts to disengage.
Another thing: to lengthen the pushrod why do you remove it from the pedal? I mean you can turn the pushroud without removing it, does that depend on the model year?
Cheers Thomas
#10
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Howdy,
I was surprised to see this post, as I'm going to let out my adjustment today on my list of things to do.
I see that the clutch in this car has to be pushed to the floor, versus pushed about a couple of inches on other cars. That's the way it is on mine, at least.
I have only done a preliminary bit of work on the clutch. And my tranny and clutch have 3000 miles on them, so I'm assuming they are good.
I used a syringe to pull fluid out of the slave. It's evidently not the best way to do it, but I'm doing the easy way first. And it's worked well for months.
I'll be loosening up my pedal for that 0.5 mm or so, today. Right now there's no play.
My take on the clutch freeplay- The distance isn't important. I believe it's just to have some play to know that the clutch is freely disengaged. In fact, I think one can have no freeplay at all, as long as they know they are right at the end of the travel. What I'm saying is the book calls for some play, so that there is certainty the clutch isn't engaged. Or another way of putting it- the play is just an indicator that the clutch pedal isn't engaging the clutch. According to other posts, there is a hole in the master that need to be unobstructed by the master piston when the clutch is disengaged, on some models.
If all fails, there are a half dozen things to check. Fluid level, air in the lines, master cylinder, slave cylinder, and clutch plates.
I was surprised to see this post, as I'm going to let out my adjustment today on my list of things to do.
I see that the clutch in this car has to be pushed to the floor, versus pushed about a couple of inches on other cars. That's the way it is on mine, at least.
I have only done a preliminary bit of work on the clutch. And my tranny and clutch have 3000 miles on them, so I'm assuming they are good.
I used a syringe to pull fluid out of the slave. It's evidently not the best way to do it, but I'm doing the easy way first. And it's worked well for months.
I'll be loosening up my pedal for that 0.5 mm or so, today. Right now there's no play.
My take on the clutch freeplay- The distance isn't important. I believe it's just to have some play to know that the clutch is freely disengaged. In fact, I think one can have no freeplay at all, as long as they know they are right at the end of the travel. What I'm saying is the book calls for some play, so that there is certainty the clutch isn't engaged. Or another way of putting it- the play is just an indicator that the clutch pedal isn't engaging the clutch. According to other posts, there is a hole in the master that need to be unobstructed by the master piston when the clutch is disengaged, on some models.
If all fails, there are a half dozen things to check. Fluid level, air in the lines, master cylinder, slave cylinder, and clutch plates.
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Thanks Gregg! I look forward to your update. Reason is, my short legs require me to either sit too close to the steering wheel for comfort or use the clutch pedal with my tippie toes to get it all the way to the floor and not crunch gears.
Good luck on the alignment!
Good luck on the alignment!