I spoke with my vendor. He mentioned that a couple other users of this
part brand
had the same issue. It may be that the supplied O ring is not thick enough.
This was one of my initial concerns or observations. In solving the issue,
I installed a spare O ring made by a different company.

In other words, the thermostat design is likely not the issue. And, as
I'd wondered,
the plastic elbow can warp over time. But that's not new info.

I posted this here not just for the straggling few of use running VW inlines
but in case this same maker supplies thermostats for the WBX.

Neil.

On 12/29/15, Neil N <musomuso@gmail.com> wrote:

> I mention that as installing the thermostat on the ABA engine is slightly
> tricky
> and I obviously haven't done it many times. Twice really.
> Regardless, the Calorstat thermostat I bought seemed to make the job
> harder.
....
> Vendor said this part fit several other vehicles. e.g. Volvo.
> It c/w several different gaskets. In no way could I get the coolant elbow,
> thermostat, and O ring gasket installed without seeing a very slight
> leak.

--
Neil n

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