This is a report on the fix for the problem I had with my pulsating brakes.
The email below discusses all my original symptoms. After the original
email I rotated the drum brakes to oposite wheels. The pulsation
followed the drum and this was verified by clamping off the rear bake
hose. I took the drum and had it checked and turned slightly one more
time. The pulsation was still there.
I gave up and took it to my local VW shop. They told me the drums were
worn out and not within the minimum thickness. They put on Brembro
drums, lightly sanded the brake shoes, and the vibration is completely
gone. They told me that even if they are turned and round, if they are
too thin they will warp while you are using them and cause pulsing.
All I knew they may have been the original drums with 260,000 miles in
them. Thanks for everyones help. Hope this is useful for someone in
the future.

Blake Heinlein
http://blakeheinlein.googlepages.com/

On Thu, Mar 26, 2009 at 1:42 PM, Blake Heinlein <blakeheinlein@gmail.com> wrote:

Hi everyone, so here's my situation.
My 1984 Westy has a pulsating brake pedal and undulating slowing
during braking. I can actually see my leg move up and down while
braking. I need help troubleshooting my problem.

I have been able to isolate the�culprit�it to the back right wheel.
How do I know this? If I clamp off the rubber brake line to the right
rear wheel, the brake pedal is perfectly smooth and the stop is
smooth. That means that 3 of the brakes are working perfectly.

Here is the work I have done and in order that is was completed. I
always did the work to both sides of the van at the same time.Replaced
rear brake shoes about 1-1/2 years ago (Did not turn the rear drums at
this time)

Had a local repair shop replace the rear wheel bearings about 1 year
ago (This is the only work I hired out)Bleed brake system and flushed
with new fluid (The rest of the work was done in the last 2 months.

Installed new rear drums and the pulsation was worse so I returned
them.Turned the original rear drums and installed themInstalled new
front wheel rotors and brake padsGreased and adjusted the front wheel
bearings

Symptoms and/or current conditions of van:There are no wheel
vibrations while driving the vanNone of the brakes drag when the brake
pedal is up (brakes off)The parking brake engages the rear brakes at 4
clicks. There is free play in the parking brake linkage when they are
released.

The brake pedal feel is firm and high and does not leak down. The best
I've had since I've owned the van.The van stops quicklyThe drum brakes
are adjusted so they just slide on and then I backed the ratchet off
by 3-4 clicks.

None of the 4 brake cylinders leakI have checked that all the rear
brake shoe linkage is properly assembled.The drum brake positioning
bolts are installed.The drum brakes are free of dirt and grease at
installation. Lightly sanded pads to removing any glazing

Here are some of my thoughts about what might be wrong:Axle is bentHub
(part with the wheel studs) is bentSomething wrong with wheel
bearingsSomething wrong with proportioning valve to rear wheel

The axle nut is not torqued correctlyBrake pads don't seat properly in
the drums (i.e. the curvature�radius��is different)
So these are all my thoughts. Now it's your turn to help solve the
puzzle. Thanks in advance to everyone.

Blake HeinleinSacramento, CA
http://blakeheinlein.googlepages.com/

-- 
Blake Heinlein
http://blakeheinlein.googlepages.com/