Re: Clutch replacement

[steveb@falcon.kla-tencor.com (Steven Buchholz)]

 # I am getting ready to tackle the clutch on my 4ksq. Any helpful hints? I
 # bought the car needing a clutch so the price was very cheap. The rest of
 # the car is in great shape. Can't wait to drive it. The last Audi we owned

Hi there Justin!

Well, I'm in a very similar situation.  Doing a clutch on the 4kQ is 
really pretty easy ... perhaps the most difficult thing is disconnect-
ing the downpipe.  I got mine off pretty easily once I got the right 
configuration of extensions and accessed it throught the passenger's 
side front wheel well.  Let's see if I can give you some pointers 
based on my experience ... which is for an '85 4kQ.  Any newer 4kQ 
should be the same, but an '84 is a little different (things like the 
center diff lock actuator).  

I'd recommend that you evaluate the car and buy a few things before 
even starting the project.  That way you can just pull the tranny, 
swap the clutch and put it all back together without getting side-
tracked.  Here's what I needed:

 - Drive flange "gaskets" (3 total) - The part for the prop shaft is 
   different than the ones for the front half shafts.
 - Transmission mounts (2) - One was obviously trashed from oil over 
   the years, but even though the right side is relatively shielded 
   it was busted up as well.  Check the motor mounts while you're 
   looking.
 - Make sure that you replace the throwout bearing and the sleeve 
   that it rides on.  Use only a metal sleeve ... the OEM part may 
   be plastic, and plastic parts are notorious for causing problems.  
 - Check the outer CV boots - doing the clutch will involve removing 
   the half shafts [which I highly recommend doing ... I have done 
   trannies in the past leaving in the half shafts, but it is so easy 
   to R&R them on the 4kQ].  CV boots are so cheap and easy to do on 
   this car I almost recommend doing them out of course, but if they 
   look good you can let them go.  
 - I went with the Sachs clutch rather than buying one from Audi ...
 - You might want to consider replacing (or at least rebuilding) the 
   clutch slave cylinder.  The clutch fluid is rarely serviced, even 
   by Audi techs ... I've never actually had a slave cylinder fail, 
   but it can and does happen.  

There are a few tools/resources that you should consider having for 
the process:

 - Bentley manual - The manual does cover the process in good detail.
 - Clutch centering tool - need I say more?
 - Tranny mount for floor jack - This is not a mandatory tool, but 
   the tranny is a bit too heavy for me to muscle around w/o a floor 
   jack.  A tranny mount that allows you to adjust the angle can 
   really help when the time comes to put everything back together.
 - Some means to hold up the front of the engine - I kinda screwed 
   up here.  When you remove the tranny the engine will naturally 
   tilt forward on the engine mounts.  Audi shouws a special tool 
   that can be used to hold the engine in place after the tranny is 
   disconnected.  I've never used one before, and I've been able to 
   manage by using a second floor jack to lift up the front of the 
   engine.  You don't need the Audi spec'd tool, but you must have 
   your strategy for dealing with this problem decided up front [no 
   pun intended ;]

Here are a couple of ideas for things to do or check while you're 
in process:

 - Check the state of the shift linkage.  There is a ball that tends 
   to work loose that can cause sloppy shifting, and there is a 
   locating rod that has a couple of plastic sockets that can break 
   over time.  I needed to use a punch to connect the ball on the 
   linkage more securely.  
 - Remember to check the vacuum lines for the center diff actuator, 
   don't forget to remove them when dropping the tranny, and remember
   to hook them back up again when putting the tranny back in.  They
   are located in a place that might make them easy to forget otherwise.
 - You're going to be pulling the starter ... does it need to be rebuilt
   or replaced?
 - add some moly grease to the front CV joint on the prop shaft while
   you have access to it ... do the same for the inner CVs on the half
   shafts.
 - check the OXS ... it's a bit of a PITA to access when the exhaust
   system is assembled.  Universal 3-wire replacements can be obtained
   for much less than $100.
 - check the hoses that are difficult to access when the car is together.
   I'm thinking primarily about those under the battery and at the back
   of the head.  

If you're prepared a clutch can easily be handled in a weekend.  Good luck!

Steve Buchholz
San Jose, CA (USA)