Thursday, March 8, 2012

The Phillip Way or Rear Disc Rebuild

Well, there are always two ways to do a job.  The right way and the Phillip Way.  And since these are two opposite ways of doing things, you may assume, Dear Reader, that the Phillip Way is indeed the wrong way.

So it is and so it has been for many years.  This applies to many things around the house, like plumbing and electricity and screen door and toilet float installations, and it has not changed now that I am working on something as different or substantial as the Ghia.

Built the Phillip Way..wrong!
For example, one or the other of you sharp-eyed Readers will have noticed that I have already installed the new disc brake kit on the rear, complete with spacers, o-rings, gaskets, brackets, bearing caps and lots of grease.

Well, not exactly complete.

In fact, in keeping with Phillip's Way, I left a couple of things out the first time around.  No, this was not an accident, but in keeping with the instructions. Honest!  I know, I know, I am not supposed to read those things, but after putting it together, the brake calipers just didn't fit correctly around the rotors.  They weren't centered in the gap so I had to see if I had done something wrong.

All the parts laid out...
Packed with grease
Of course, I had done something wrong, but as it happens, what I did was actually according to the instructions.

Now, how, you ask, is that possible?  Well, what if the instructions are wrong?  Why they would be wrong is a mystery to me, but I can say with some certainty that putting the disc brake kit together excatly as prescribed in the instructions does not result in the the proper fit.

Big o-ring and paper gasket
Next is the thin 'thrust washer'
It has to do with two parts, a thin spacer or shim, and an o-ring.  Both parts, according to the instructions--are to be omitted from my particular type of transmission and driveaxle assembly.  Known as IRS (Independent Rear Suspension), the type of drivetrain in my 1974 Ghia is different than the kind that came before it, the trans-axle, or 'Swing-Axle' as it is sometimes called.

Followed by the small o-ring...
...the bearing cap goes on.
Without getting into the differences between the two drivetrains, it's worth noting that they are completely different in the way they go together, but the function is similar enough that most of the parts are interchangeable.

Most of the parts.  Not all the parts.

With the rotor on the axle...
...the caliper can go on.
The bottom line is that, after days of experiments, I finally come to the conclusion that the two parts that were supposed to be omitted according to the instructions were actually supposed to go on after all.

So, I started over and rebuilt both sides, this time with all the parts.

First I gathered everything together.  Next step, I loaded the bearing with grease, put on the paper gasket and the large o-ring.  Next I put on the thin thrust washer (shim) and on top of that went the small o-ring.  The bearing cap, with the large spacer inserted into it in advance, slid onto the axle and covered up the whole set of pieces.

The rotor is now centered in the gap.
Once it was bolted down, I installed the caliper (again) and this time, voila!  It all lined up perfectly.  I do not know why the instructions were wrong.  I discovered the solution only by trial an error because the 'solutions' I found on the net were either wrong or incomplete at best.

I am not absolutely sure this is right, but it sure looks right and it even makes some sense.  Of course, that's not the Phillip Way, but it will get my Ghia built correctly!

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