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 Posted: Aug 14, 2012 12:15PM
Total posts: 726
Last post: Oct 15, 2013
Member since:Jun 19, 2001
US
Quote:
Originally Posted by DRMINI

1. When the slave cylinder seal wears, it sucks air in on the upstroke. If you have this prob and can't get rid of air, change the seal.

2. Current slave cylinders (the shiny ones) which come from UK (not made there, think east>>>> have the wrong shape plastic spreader bit inside the seal. If you buy one, take the corresponding bit out of your old cylinder and use that.

DRMINI, is this the shiny cylinder you were refering to?  I bought it while I was in Italy, so there is a good chance I did not buy it from our host. No matter how much I bleed, vaccuum or adjust, the only way I can get it into gear is to double pump the clutch.  If this is the case, will this fix it?  http://www.minimania.com/part/8G8446/Clutch-Slave-Cyl-Kit---Sprite-Midget-Mini-Pre-verto

 Posted: Aug 13, 2012 07:01PM
Total posts: 9502
Last post: Sep 21, 2014
Member since:Dec 3, 2002
US

Do the Mini brakes the same way you did the clutch.

 Posted: Aug 13, 2012 10:13AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

With brakes, I would have someone pump the brakes then hold te dedal as I opened the bleed valve then close the valve.   I would repeat this process until the air was out.    With the clutch, you just press the clutch pedal and open the valve, close valve and repeat.   No pumping with the clutch.   The brake method may not be correct with mini's, it is a carry over from working on too many chevy's and fords.

 Posted: Aug 13, 2012 09:16AM
Total posts: 9492
Last post: Sep 21, 2014
Member since:May 13, 2001

I've always bled brakes and clutch the same way ie the way you bled the clutch. How does your brake bleeding method differ from the way you did the clutch.

The power of keen observation is often viewed as cynicism by those who don't have it. G.B.S. Sarcasm is the lowest form of wit. Oscar Wild

 Posted: Aug 13, 2012 07:36AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

For those reading, I apologize for not posting the resolution earlier.   I just got excited about being so stupid.   We rebuilt the master and slave cylinder, replaced the hardline from the master to the flex line and still could not bleed the system until I read the manual.   I was trying to bleed the system like a brake system (it did not work).   I hooked a drain line to the slave, pushed on the pedal, opened the valve and amazing the air that expelled.   Did this about 4 times and the system was clear.   Read instructions is key.   Thanks to everyone for your replies.   We are running great now.

 Posted: Jun 27, 2012 05:08PM
Total posts: 836
Last post: Sep 18, 2014
Member since:Oct 18, 2011

I'd suggest it could be something silly like a seal in backwards??  I've done stupider things myself and the more you look at it the righter it seems...... until someone points out the error ....DOH..

Of something off the wall like a crack in the master or slave bore???

You did try the earlier suggestions of bleeding the slave while holding it vertical/holding the piston at the bleeder end of its bore???

Cheers, Ian

 Posted: Jun 27, 2012 12:16PM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

The issue continues.  I had to take a couple weeks off this project but back on again now.    After rebuilding the master cylinder and checking the slave cylinder, I took advice that the hard line might be bad, the one from the master cylinder to the braded banjo line,  I had a new line built and installed it.  I bench bled the master cylinder again and started to bleed the system.   I got pressure thru the slave but had air and kept bleeding .   I stopped to refill the master and when I went back to bleeding, there was no pressure.   I had to take the hard line off and basically bench bleed the master again.   I got pressure and reinstalled the line and went back to the slave to bleed and got pressure again with some air.   I stopped for a minute or two and lost all pressure again.  

Sound like a bad master to anyone or are there are any suggestions beyone replacing everything and just start from scratch?    Thanks for the past and any future replies.   Don't have any hair left to pull out.

 Posted: Jun 1, 2012 10:34AM
Total posts: 147
Last post: Jul 17, 2014
Member since:Apr 30, 1999

have your friend push in on the clutch pedal

open bleed screw, clutch pedal should go to floor, bleeding air

leave pedal pressed against floor

disconnect push rod and push rod into clutch cylinder this should remove all remaining air in slave cylinder, close bleeder.

don't forget to use bleeding hose and catch can and top off master cylinder.

Rocky in Merritt Island, Fl.

--WETSU--

 Posted: Jun 1, 2012 12:17AM
Total posts: 208
Last post: Sep 22, 2014
Member since:Apr 21, 2006

A young friend recently fitted a brand new slave cylinder to his 1100 and couldn't get it to bleed. 
After a lot of work trying everything he knew he eventually gave up and pulled it back off.
He then discovered that there was no piston and seal inside the cylinder.  

I just buy a 7/8" seal and hone the cylinder. Good as new.  

 Posted: May 31, 2012 09:31PM
Total posts: 8172
Last post: Sep 17, 2014
Member since:Oct 27, 2000

1. When the slave cylinder seal wears, it sucks air in on the upstroke. If you have this prob and can't get rid of air, change the seal.

2. Current slave cylinders (the shiny ones) which come from UK (not made there, think east>>>> have the wrong shape plastic spreader bit inside the seal. If you buy one, take the corresponding bit out of your old cylinder and use that.

Kevin G

1360 power- Morris 1300 auto block, S crank & rods, Russell Engineering RE282 sprint cam, over 125HP at crank, 86.6HP at the wheels @7000+.

 Posted: May 31, 2012 06:58PM
Total posts: 836
Last post: Sep 18, 2014
Member since:Oct 18, 2011

If there's no fluid leaking out from the flex line joins when you press the pedal its pretty unlikely that air is being sucked in on the return stroke...

The design of the slave means that, when bleeding, you can have clean fluid coming out the bleed niple but a big air pocket in front of the piston - and consequently, no clutch movement.  I suspect that is why Islandblue stands the slave at an upright angle (correct??) when bleeding. 

Another approach (that I use) is to uncouple the slave rod and physically push the slave piston back to the bleeder end of the slave (open the bleed valve when pushing the piston in). I then hold the piston back while pressurising the system using a Gunston Ezibleed at a couple of psi air pressure.  Once all the air is expelled, reconnect the slave rod and then you will need several pumps of the pedal to push the piston back to its operating point.

Another possibility (BTDT) is to concentrate so hard on getting the air out that you forget to check the level of fluid in the master cyl - at some point you run out of fluid and start pumping air (rather than fluid) into the system

The only other expanantions that I can think of are:

a. the master cyl bore is damaged (pitted??)

b. you installed the wrong master cyl seal kit or

c.  the kit was not correctly installed...

But, knowing its a Mini, I would never (sic) say that there is not some other explanation....

Cheers, Ian

 Posted: May 31, 2012 11:50AM
Total posts: 11178
Last post: Sep 21, 2014
Member since:Jan 22, 2003
CA
Quote:
Originally Posted by Cup Cake

There's a threaded collar and lock nut on the end of the throw out bearing make sure it hasn't come loose and threaded in. Check for wear on the push rod eye and the ball on the end of the clutch arm. It could be that your clutch hydraulic system is working OK but there is something wrong in the linkage.

If the stop nut had threaded in...there would be no pedal travel at all ( when pressurised )...pedal would be solid.  I don't think that's what the OP is experiencing.

The plunger socket is a common wear item also.....will severely limit clutch movement

http://www.minimania.com/web/Item/22A180MS/InvDetail.cfm

 

 

"Everybody should own a MINI at some point, or you are incomplete as a human being" - James May

"WET COOPER" (Terry Snell of Penticton BC ) - Could you send the money for the unpaid parts and court fees.
Ordered so by a Judge

 

 

 

 Posted: May 31, 2012 11:27AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

Understand what you are saying about the arms etc.   However, when I bleed the system and open the bleed valve, there is no fluid coming thru the system to move the rod from the slave.   Seems that the system is sucking air when I pump the pedal.   I have a suspicion that it may be something to do with the steel line from the master cylinder to the braded line.   I am going to do a couple test that Mike from Minisport suggested.   I may even replace the steel line just to be sure all the flanges are good.   I will post the outcome.

 Posted: May 31, 2012 10:32AM
Total posts: 9492
Last post: Sep 21, 2014
Member since:May 13, 2001

There's a threaded collar and lock nut on the end of the throw out bearing make sure it hasn't come loose and threaded in. Check for wear on the push rod eye and the ball on the end of the clutch arm. It could be that your clutch hydraulic system is working OK but there is something wrong in the linkage.

The power of keen observation is often viewed as cynicism by those who don't have it. G.B.S. Sarcasm is the lowest form of wit. Oscar Wild

 Posted: May 31, 2012 09:53AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

well here we go with more clutch issues.   I removed the master cylinder and the fluid was filthy which indicated a deterioration of the rubber seals so I rebuilt the master cylinder and bench bled with good pressure.   I tried to bleed the system and got nothing from the slave cylinder so I removed the slave cylinder and bench bled it and got good pressure.   Reinstalled the slave and bled, got good pressure but still had air when bleeding.   All of a sudden I lost all pressure when pumping the clutch.   Any ideas  would be appreciated.  I have installed a stainless hose from the copper  line to the slave.

Thanks

 Posted: May 20, 2012 09:42AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

It's hard to believe there is that much air in the system haha.  I'll check that hose, and try bleeding the system the way you suggest and let you know what I find.  Thanks for the help.

 Posted: May 20, 2012 09:20AM
Total posts: 2988
Last post: Sep 7, 2014
Member since:Feb 9, 2002
US

It is probably just air in the system.  I remove the slave cylinder so I can bleed it with the bleed nipple straight up to get all air out.

I have also experience an old deteriorating hose from the master to slave that had a flap of rubber that blocked fluid flow, reducing movement of the shaft.  If your hose is the old rubber kind, consider replacing it.

 

"I drive a Mini. What are you compensating for?"

 

 Posted: May 20, 2012 09:12AM
Total posts: 58
Last post: Aug 28, 2014
Member since:Jun 6, 2008

I was out driving the Mini (1275cc) the other day when I started to loose pressure in the clutch pedal.  After I pumped it up a few times it seemed to work fine, but the next morning there was no pressure at all even after pumping the clutch.  There is plenty of fluid in the reservoir, but when we tried to bleed the system all we get is air being released.  Also the shaft going from the slave cylinder to to the clutch is not not moving at all.  It sounds like the slave or the master cylinder is going out, but there is not even a thousand miles on them.  Any ideas as to what it could be?  Thanks in advance for the help.