[T3] 66 Squareback Now Mine

[Jim Adney]

On 6 Nov 2015 at 3:41, Soren Jacobsen wrote:

> On 05/26 07:52, Jim Adney wrote:
> > 
> > I can probably come up with a Type 3 hockey stick if anyone needs 
> > one, but note that '72 cars with vacuum adv/retard got a special one. 
> > I won't have one of those.
> 
> (catching up on ancient email...)
> 
> Really?  My parts books don't have updates through the very end of the
> line, but they do have some 1972 info.  I see two hockey sticks, one
> used through VIN 433785, May 1964 (113 311 541A) and one after that (311
> 311 541).  I do see a different nose cone being used in 1972, though.
> I've never had any exposure to 1970s T3s -- what was different in 1972?

'72 FI Type 3s came with a distributor that had both vacuum advance 
AND vacuum retard. As delivered from the factory, the vacuum advance 
was only enabled in 4th gear. To do this, there was an extra switch 
on the tranny nosecone that was activated by an additional cam on the 
hockey stick. That sent power to a solenoid valve in the vacuum line, 
which let vacuum thru only when energized.

I always felt that it was overly complicated, so I generally just 
plumb the vacuum advance hose directly to the distributor, enabling 
the vacuum advance in all gears. Given how the vacuum advance works, 
it's only likely to come into play in 4th anyway.

Probably the only reason I know all this is because I once owned one 
of these cars. It's a messy system, so if you have one of them, 
you're really better off converting it to a stock '73 system. This 
requires replacing the distributor, the brain, and the pressure 
sensor. You can do all that for about the same cost as replacing the 
'72 vacuum can, which was a failure-prone part.

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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