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7B77B62A-A423-4809-954D-C08D38B32107_1_201_a

I have a car with an aftermarket internal clutch slave cylinder, pressure plate, and disc.  The slave is relocated on the inside of the bell housing and it surrounds the input shaft (no photo of this).  You can see the braided line that goes into the bell housing where the factory clutch actuating shaft would reside.  

The clutch is slipping, particularly on the freeway when accelerating.  Initially I concluded that the clutch needs to be redone.  But after getting a better understanding of the factory slave and clutch configuration, I am wondering if the clutch in question above is only out of adjustment.  Yet it seems that there is no adjustment for this setup without pulling the transaxle.  What is your experience with this setup?

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Last edited by stevebuchanan
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Adjusting the position of the throwout bearing is not done with shims.

it is done with male and female threads  

in the photo below the far right piece is a spacer notched to fit over the input shaft tube mounting bolts.

next is an aluminum piece that slides over the input shaft tube and has full length male threads.

The next piece is the piston assembly and it has matching female threads.

The bearing is a press fit onto the piston assembly snout.

17DBF809-90B2-45D6-8798-676A76BE4D87

that should give you a better idea of what to expect once you pull things apart

Larry

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...You are Not going to like hearing this, and this has nothing to do with a slipping clutch...

FWIW, In the Photo, the Half-Shaft Flange Mounting BOLTS are Installed from the Wrong Direction. YES! It makes a Difference. The physics of Bolt Fasteners dictates..."The Bolt HEAD Must contact with 'The Most Rigid Base' "*. That Base would be the Transaxle Drive Flange. The Bolts are to be Installed from 'Behind' the Drive Flange. Since you will be pulling everything apart, it will be an opportunity to correct this. Not just My Opinion, just Good Engineering.

* And in the case of a 'Rotating Assembly', such as a Helicopter 'Rotor-Head', the Bolt Head Always Points in the Direction of Rotation. If, in the Worst-Case Scenario, the Nut should vibrate Off, the Bolt would Stay in position.

The Praise: It looks as if You have Eliminated the 'Split-Washers'! This is Good!! I, also did this, First Thing! The 'Split Washer' is a Hardened 'Spring'. I Have seen more than One, Break, Fall Out, and the Bolt Immediately becomes LOOSE, you don't need to Guess, what Happens Next!

This is a 'Heads-Up', for All those who care to listen. We are All, Still Learning.

MJ

Last edited by marlinjack

I would have to say that what is showing in Steve’s photograph is an early version of the McLeod throwout bearing  


My experience started over 20 years ago with the McLeod throwout bearing installed by Dennis in the mid-1990s. My first rebuild went just fine. My second rebuild was difficult  

McLeod customer support is poor, and that is putting it mildly. Their rebuild kit for these bearings has retained the same part number despite being upgraded at least two times. I learned this when I ordered my second rebuild kit and what they sent had no relation to what was currently installed, having previously used  a rebuild kit with the exact same part number. Turns out they had changed the design a little bit but kept the same part number for a rebuild kit. 😳🤷‍♂️ I had to upgrade to a new bearing carrier and the larger bearing.

you’ll find McLeod cannot provide a rebuild kit for the bearing shown in Steve’s photo. He will have to do as I did and upgrade to a newer unit. IIRC they did give me a little bit of credit when I returned the early version


Larry

My existing throw out bearing is not leaking.  My only problem is that the clutch is slipping, primarily when accelerating on the freeway.  Wilkinson looked into the inspection cutout on the bell housing and thought there was plenty of clutch disc.    The throwout bearing itself seems healthy.  My plan is to set the clearance for the bearing and reassemble it after cleaning everything and putting in new shaft seals and side gaskets on the ZF.  I will be taking this all out later for an engine rebuild and just want to get the clutch slip and ZF drips fixed for the time being.

David, no worries.  As Larry stated, this setup has evolved over the years.

I made good progress today and the resealed ZF is back in the car.  At this point there is too much free travel in the pedal and I will need to decrease the throwout bearing clearance.  I assumed I would not get it correct the first time and everything is minimally assembled.  Nonetheless, the transmission and hydraulic line have to come off to make the adjustment.  After reassembly the slave has to be bled to remove air.  Heavy lifting is required to adjust this clutch setup.

Problem is, the throwout's free clearance CHANGES WITH TEMPERATURE. As with valve lash when you adjust cold, clearance decreases with all concentric throwouts when everything is warmed up, and that takes about 30 minutes of moderate driving on the road. 

I built one out of a Tilton dirt track racing assembly back in the mid-'90s, and you need far more cold clearance than you'd think. The Tilton throwout carrier is internally fine-threaded and has a threaded ZF nose piece, so to adjust it, you disconnect the lines and rotate it, then re-bleed. It's held in place with a stripper allen-bolt, not just hanging on the lines. Once adjusted, it stays there. Haven't readjusted in 20 years. Tilton does not build one for a ZF.

The good news is, you only need to slide the ZF backwards for access while it lays on the lower subframe rails. One person can do this without an engine crane- no need to completely remove the 155 lb lump. You may need to unbolt the A/C condenser ass'y and swing it out of the way so as to slide the ZF back far enough. No need to disconnect the A/C. Good luck.

I contacted McLeod customer support and got a better understanding of this hydraulic throwout bearing.  He explained that it is self adjusting (to a point) and when installed dry with .100" clearance, then refilled with fluid, and finally purged of all air in the system then there is never any clutch pedal free play.  If the clutch disc wears more than .100" then the pressure plate may not fully deploy and the clutch could slip.  My car is almost back together and I will find out soon if resetting the dry clearance fixes my problem with clutch slip.  

Last edited by stevebuchanan

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