Monday, June 30, 2014

Vanagon Repair: Clutch Master Cylinder

We've been busy. Busy with the toddler, busy with work, busy moving, busy with planning for Baby Boy #2 due in August. Unfortunately this has left our lovely Vanagon unused for the better part of a year.

Out with the old...
To get Ruby back in prime condition, I ordered a replacement clutch master cylinder from GoWesty Auto Parts. That new master cylinder then sat in my garage for many months until I finally got around to the installation this past weekend. And as everyone who's ever done this seems to agree, it's definitely a messy task.

Just as I did with my brake master cylinder replacement, I looked to the very helpful resources on vanagonauts.com for guidance. Here's my edited version based on my own experience:
  1. Remove the shroud covering the instrument cluster to gain access to the hydraulic fluid reservoir. Also remove the lower steering column cover secured by two screws.  Carefully pry it off.
  2. Lay some plastic sheeting and/or lots of newspapers or rags in the footwell. Hydraulic fluid will spill during this process and can infiltrate carpeting and dissolve paint, so do all you can to prevent it from contacting bodywork. Use cold water or rubbing alcohol to clean spills from such surfaces.
  3. Siphon fluid from your fluid reservoir until the level is below the braided rubber supply hose leading from the  reservoir to the master cylinder. The fluid in my reservoir was already below that hose (due to the leak), so I didn't have to siphon.  Others have recommended clamping the braided hose in lieu of siphoning. 

    Note the broken/missing nipple.
    Easy there big fella...
  4. Removing the old cylinder. My 1990 Vanagon uses a bolt-through banjo fitting on the front of the cylinder, with a 17mm head.  Loosen and remove it.  Lots of dripping ensued from the remaining fluid in the cylinder and braided supply hose.  Be ready with rags. Lots of rags.  Keep track of the two copper washers that are used in these banjo assemblies. 
  5. Remove the two 13mm retaining bolts holding the old master cylinder in place. I used a socket, but the upper bolt was a bit tricky to access. You might have an easier time with an open wrench on that upper bolt. 
  6. You can now lower the clutch master cylinder, being mindful of the pedal-actuated rod that will slip from the rubber boot atop the cylinder. Gently wriggle the braided rubber supply hose from the nipple on the back of the old cylinder.  I stress "gently" because at this point I was dirty, sweating, pissed off, and uncomfortable, and in my frustration I ended up snapping the old nipple off inside the hose. I then had to give the hose a fresh cut above the embedded nipple.  No big deal.
  7. Installation of your new master cylinder is pretty much the reverse of removal, starting by attaching the supply hose and then carefully slipping the actuator rod into the master cylinder's rubber boot.
I then bled the system, which was actually surprisingly easy. I put a short tube over the the bleeder valve on top of the clutch slave cylinder (located in the left-front of the engine compartment) and the other end of the hose into an old brake fluid bottle to catch the fluid.  When I opened the bleeder the fluid began to flow freely.  No vacuum bleed required (as some suggest). I topped up the reservoir and let about a pint a fluid run through the system, making sure to always keep the fluid level above the supply hose. I could see lots of air bubbling through the clear tubing running from the bleeder, a good sign that I was purging the system.  And that's it!  The clutch was a little jumpy at first, but then smoothed out.  The whole process--from removal, to installation, to bleeding the system--took about one hour.  One messy hour.

Good luck.

1 comment:

  1. Even so, you should always consider the option of working with a buddy in these types of projects. It could be friend or a family member, but the learning environment is likely to be enhanced when you and your project buddy get going.
    Schultzy @ https://www.yourmechanic.com/

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