[T3] Early Front Brake Cylinders?

[snj at pobox.com]

On 07/08 14:34, Jim Adney wrote:
> I've never had a Type 3 early enough to have front drum brakes,

Consider yourself lucky! ;)  Discs are wonderful.

> so I'm not familiar with the different versions that were used on the
> '61-65 cars. The microfilm shows 3 versions. Version 2 & 3 look alike
> and use the same illustration; version 1 looks completely different.

There are four different versions, and two distinct shapes.  I guess
three versions if you exclude adjusters and pistons and refer only to
cylinder bodies.

Early (first 27k) Notchbacks and T34s used 20.64mm cylinders, which look
like this: http://images.thesamba.com/vw/classifieds/pix/4202947.jpg

Squarebacks used 22.22mm cylinders from the beginning, and Notchbacks
and T34s joined the party in March of 62.  These cylinders share the
same overall shape as the early 20.64mm versions.  Here's one:
http://images.thesamba.com/vw/classifieds/pix/4202961.jpg

For 1964 and 1965, a new shape of cylinder was introduced.  They look
like this: http://images.thesamba.com/vw/classifieds/pix/4202961.jpg

> I have some of those version 2 or 3 cylinders here that people have 
> sent me, and they all look alike except for one little detail: The 
> slot in the piston, for the brake shoe, is ~4mm wide in some and ~6mm 
> wide in others. From looking at the parts lists, only the pistons and 
> adjusters seem to be different. (VW did not sell the body castings 
> separately, so there might be some minor difference that I haven't 
> noticed.) All are 22.2 mm (7/8") dia. I don't have most of the 
> adjusters, so I can't check the slot widths in them, but I assume 
> they were the same 2 widths.
> 
> Can anyone tell me if this is the difference and, if so, which one is 
> the earlier version?

Yes, this is indeed the difference.  The earlier (1964) one is the
narrower version.  I've not seen any differences in the bodies.

> And, BTW, if you have brake parts that you think might be useful 
> someday. Please don't just set them aside to rebuild later, when you 
> need them. Brake parts left sitting with brake fluid in them will 
> rust badly in storage and become much less likely to be rebuildable. 
> Rebuild them NOW, then store them dry.

And since we're on the topic of best practices for brake components, be
sure to apply some brake paste on the sealing surfaces when reassembling
the cylinders.  I use ATe's paste (Bremszylinder-Paste), pictured here:
http://blef.org/vw/brakepaste.jpg

That only applies to glycol-based brake fluid users, of course.  I'm
sure Jim will correct me if I'm wrong, but those of you using silicone
brake fluid should just use a bit of fluid for lubrication upon
assembly.

Soren