Before assuming the worst, I really think you need to rule out the
obvious... do you have a coolant leak?

After I did my cooling system I had to go around chasing leaks for a few
weeks. Just needed to tighten the worm-type hose clamps. Something about
new hoses and new clamps makes em not seat quite right the first or second
time you tighten them sometimes. The factory ones seem to hold just fine,
for me.

Gowesty sells a really cool little pressurization pump. It will allow you
to know for sure whether you have a leak(s) or not. It will then make it
really easy to find those leaks, most of them wont start leaking until
around 12-15 PSI (which makes sense with your sudden loss at highway
speeds... it takes a while at hot temps for the coolant to get to those
pressures). Don't go much over 15 PSI. The Gowesty instructions say to go
to 20PSI... but that just seems dangerously excessive. The pump also makes
bleeding the system a breeze. If fact, it makes it downright easy.

On Wed, Apr 29, 2015 at 12:29 AM, Neil N <musomuso@gmail.com> wrote:

> Can't say exactly but shop was about 3 blocks uphill from sea level.
>
>
> On 4/28/15, OlRivrRat <OlRivrRat@comcast.net> wrote:
>
> >       What Altitude are you @ & were those numbers AdjustedForAltitude ~
> >
> >
>  ORR ~ DeanB
> >
> > On 28 Apr , 2015, at 6:49 PM, Neil N wrote:
>
> >> engine compression test done a while ago by a Vanagon shop showed:
> >>
> >> 130      120
> >> 140      140
>
>
> --
> Neil n
>
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
>
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
>
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
>
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
>