[T3] Master Cylinder workover

[Dennis Stiefel]

> my 71 still has the master I put in it in 1988 when I got it, still 
> the DOT3 or 4 as I didnt want to keep eating the brake light switches 
> and havent converted yet.

I'm not at all convinced that the DoT-5 has anything to do with failing
brake light switches. The failed switches that I've cut apart have shown no
sign of brake fluid having gotten past the seal that separates the fluid
from the moving parts, where the failures occur. 
While it's possible that there were tiny amounts that got thru but were not
visible, I remain skeptical. Most of the failures I've seen happened due to
melted plastic parts, parts that got too hot due to the current running thru
parts next to them. In some switches those parts now appear to be made of
metal, so that may fix this problem.  

Remember: Coincidence does not imply causality. I think it's likely that we
just started using DoT-5 about the same time that our OG switches started to
run out of lifetime. I just ordered some new German (FTE) switches. They are
expensive, but I thought they might be better quality, so I may install one
of them in my rebuilt MC. 
Then we get to see how long it lasts. Of course it's also possible that the
new German switches are nowhere near the quality of the old ones. If any of
you would like to try some of them, I can sell them for $18 plus shipping.

In the meantime, if you are still using DoT-3 or 4, you should do a complete
fluid flush every 2-4 years, just to reduce the corrosion that happens as
that fluid absorbs moisture. Leaving old DoT-3 or 4 in a system for a long
time is just asking for major brake expense down the road.

DoT-5 does not absorb moisture, so periodic flushing is not necessary, and
it's a much better rubber to metal lubricant, so the seals last MUCH longer.

BTW, when I called to buy the new German switches, I asked the salesman if
they were really better than the cheap ones. His answer was that they get a
lot fewer complaints about them. That could mean nothing, but there's at
least the implication that there are people out there having trouble with
modern cheap switches and DoT-3 and 4 fluids, too. If that's the case, it
would be unfair to blame the DoT-5.

--
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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When I got Clementine going back on the road in the fall of 2013. The
original forty-something year old switches went out about a month after I
started driving her again. I had some from the parts car and swapped for
them and they lasted about 6 months.  Then I got some new ones that said
made in Germany on the box.  About a month after that one of them started to
leak fluid. Took it back for another one. The FLAPS guy looked at me odd
when I said I need DOT 5 to go with this. That was a little over a year ago
and no more issues so far. 

Dennis Stiefel
72 Fastback FI MT (Clementine)
70 Fastback Carb MT (school project)
71 Stander Beetle (now brother's car)
88 Golf (oldiest son's car(
Rainsville, AL