Sunbeam brakes (or is that breaks?)

[louis@nil.cs.utah.edu]

Hi all,

I have been lurking on the list for over a year and have found the
information posted here most interesting and dream inspiring!

I have a question regarding the brakes on a 67 Sunbeam Alpine.  They
are power assisted with a Girling MK2A Servo unit (completely rebuilt 2
years ago) with front disks and rear drums with self adjusting wheel
cylinders.

At the end of last season, the brakes became spongy, as if they needed
bleeding. I checked the reservoir and sure enough, no more fluid.  I
topped off the level, bled the brakes but I couldn't get all the air
out of the system.  Since snow was going to start, I put the car up
for the winter.

This spring, I went back to the brakes.  Nice and spongy.  I can pump
them up (3-4 times) and get good pressure.  If I then hold the brake
pedal down, it keeps its position (and pressure) for 30-40 seconds but
then starts to decrease its level.  I cleaned every external joint in
the brake system and had a friend pump the brakes while I searched for
a leak.  None evident.

My questions are:

        1) The guys that rebuilt the power unit replaced all fluid
           with DOT 3.  Is this OK?  I read in the triumph.cs archives
           that DOT 4 is better, since 3 will rot rubber seals.

        2) How does one remove brake nipples (rear) that are stuck and now
           unfortunately stripped on the outside.  Can I use heat?
           Must I replace the wheel cylinder?

        3) Any clues to where I should look for the leak?

Thanks for any help and/or advice,

Louis



---
Louis Collins                e-mail: louis@nil.mni.mcgill.ca          
NeuroImaging Laboratory, Montreal Neurological Institute        
3801 University St., Montreal, Quebec.  H3A 2B4