Clutch problem diagnosis tip.

[Gisli Ottarsson <gisli@master.adams.com>]

Here is something I learned the hard way on my 87 5kcstq.

I had a broken clutch with the following symptoms:

 1) Clutch died suddenly without warning.

 2) Pedal goes to the floor with no resistance.

 3) When an assistant pumped the clutch, the clutch farts into the
    reservoir through the clutch supply hose.  (In my defense, I
    didn't notice this very significant symptom until much later).

If this happens to you, check out the master cylinder. 

Here is a brain dump of a few random items I picked up on my loooooong
way to correctly diagnosing and fixing this problem.  Note how when
faced with a choice between a 2 hr. master cylinder job and a 4
weekend complete clutch job I shrewdly chose to try the latter first
:-(

 - If you need to work on *anything* toward the left-rear of the
   engine compartment bite the bullet and rip out the wastegate first.
   It will save you a lot of skinned knuckles.

 - To drive out the lock pin that holds the clutch slave cylinder in
   place get a hold of the correctly sized punch, then piece together
   a few socket wrench extensions and go in through the passenger side
   tie rod hole.  You'll need to smack this contraption quite hard to
   drive out the pin.  Don't be shy.

 - Once you've cleared a path to the slave cylinder, might as well
   replace the steering rack.  $180 or so from Jorgen Automotive
   (http://www.jorgenauto.com).  Loosen and *remove* the bolt that
   passes through the steering column on the driver's side of the
   firewall.  When disconnecting the two hydraulic hoses to the rack
   remember which hose goes where.

 - Don't believe Blau when they tell you that while you are replacing
   the clutch disk et. al, you might as well replace the pilot bearing
   in the end of the crank.  To actually do this you should either be
   a glutton for punishment or have access to a massive arsenal of
   tools.  Make sure that this bearing actually needs to be replaced.
   I removed mine molecule by molecule.

The moral:  Try that master cylinder first, especially when it is
doing a jacuzzi number with the reservoir.

  Gisli


-- 
Gisli Ottarsson, PhD                     
Mechanical Dynamics Inc.            gisli@adams.com    
2301 Commonwealth Blvd.             Tel: 1-734-913-2550
Ann Arbor, Michigan 48105           Fax: 1-734-994-6418