Clutch hydraulics adjustment(?)

[HazN]

After a plethora of distractions, I now have a new clutch master installed and juiced up. I road tested it today and have a few questions.

After driving my 500 for months, I have muscle memory to clutch feel. Pedal resistance in the X seems kind of low. Do I still have air in the line?

The clutch pedal adjustment is listed in the shop manual as being a touch over 7 inches. Between what points is this measured?

The engagement is rather close to the floor for my taste. Is this adjustment done by the rod at the slave?

Thanks in advance for your insight,

 

[artz1731]

After a plethora of distractions, I now have a new clutch master installed and juiced up. I road tested it today and have a few questions.

After driving my 500 for months, I have muscle memory to clutch feel. Pedal resistance in the X seems kind of low. Do I still have air in the line?

The clutch pedal adjustment is listed in the shop manual as being a touch over 7 inches. Between what points is this measured?

The engagement is rather close to the floor for my taste. Is this adjustment done by the rod at the slave?

Thanks in advance for your insight,

From my experience with at least three master replacements the key is getting all the air out of the system.
There are multiple threads on the subject if you do a search.
As long as you don’t have any play between the spring and the clutch arm at the slave you are good to go. There really isn’t any other adjustment.
You probably still have air in the system if it feels different than before.

 

[Waterbury]

I looked around a good bit when bleeding my clutch on here, but couldn't find a good picture/video of proper rod travel on the slave. Mine engages higher than it did before. Still not so confident that it travels far enough. Didn't have much luck adjusted it with the two nuts either. Regarding that 7" measurement mentioned, I too would be curious.

 

[MikeHynes]

After a plethora of distractions, I now have a new clutch master installed and juiced up. I road tested it today and have a few questions.

After driving my 500 for months, I have muscle memory to clutch feel. Pedal resistance in the X seems kind of low. Do I still have air in the line?

The clutch pedal adjustment is listed in the shop manual as being a touch over 7 inches. Between what points is this measured?

The engagement is rather close to the floor for my taste. Is this adjustment done by the rod at the slave?

Thanks in advance for your insight,

The clutch is engaged when the piston in the slave cylinder moves out. The distance it moves is determined by the amount of fluid the master pushes out. If there is air in the system the clutch pedal will move before the slave piston moves. You can easily check this by yourself by pushing in on the clutch pedal with a long stick - like a broom stick - while you watch the slave. You should be able to feel the clutch pedal take up any slack before it engages the master. If the master is engaged, and the slave doesn't move, you are compressing air and not moving the piston in the slave.
The amount of resistance is determined by the springs in the system. There is a spring in the master and a spring that pulls the throwout bearing arm back. There is little resistance from the spring in the master, most of the resistance will be felt from the spring that returns the throwout bearing arm. Early cars had a stiffer spring than later cars, so early cars will have a stiffer feel to their clutch. If you want to adjust the feel of the clutch, change the spring.
The engagement is adjusted through the rod that moves the throwout bearing arm. You want to adjust it so that you have a little bit of movement before the arm moves. That rod should have enough adjustment to get the engagement you desire.

 

[Dr.Jeff]

The engagement is adjusted through the rod that moves the throwout bearing arm.

Mike, are you referring to this adjustment?

Because I believe that is what the guys are saying made absolutely no difference in their clutch travel/feel, so I'm wondering if there is another adjustment somewhere? Thanks Mike.

 

[MikeHynes]

Yes, everyone is correct. That is the rod, it doesn't adjust travel or feel. You adjust that rod so that when static, the throw out bearing is very close to, but not touching the pressure plate fingers.
The spring (#14 below) that returns the lever (missing in your pic - also missing in service manual pic) can affect how heavy the clutch feels (along with the springs on the pressure plate). Early cars had a heavier return spring than later cars. Most X pressure plates have relatively light springs.
Once that adjustment is made to the rod pictured above you can adjust the pedal travel on the pedal box below.

The clutch pedal adjustment in the service manual that HazN refered to is adjusted on the pedal box. I believe that travel is measured at midpoint of the pedal.

 

[HazN]

I believe this thread is now at an end. I bled the system again after the engagement was again near the floor. I am always totally amazed at how little a change can make a big difference. A bubble finally appeared abouth the size of a lentil! Everything is as I remembered it! Thanks all for your comments!

One thing. Mike showed a picture (immediately above) of the adjustment to pedal travel. Even at the bottom of the pedal, which gives the maximum swing, does not give the spacing in the manual. Another mystery.

Thanks again, all,

 

[c snapp]

Maybe I'm late to the party, but I find the adjustability of the X1/9 clutch fun and amazing. I've been adjusting clutch pedals on all my 6 X1/9's to great experience.

The top bump stop is adjustable to ensure pushrod clearance to allow master cylinder piston to return home.

I've adjusted the bottom bump stop to adjust pedal travel. I used black neoprene washers under the factory bump stop, using a longer screw. Got the idea from my grandfather's 911.

I've adjusted pushrod length at clutch slave so clutch engages where I want it to, and to ensure enough free play for the release bearing.

I've adjusted resistance pressure using different strengths of spring at clutch release arm. All my cars, including 5 speeds, have been converted for spring between release arm and slave bracket to ensure clutch slave piston returns home after every pedal travel.

As I have a bad knee, all these things help with my ability to drive the car.