Thanks for your help folks.

So, my fuel pressure gauge seems to have worked fine in this
application but I have no idea if coolant heat damaged any mechanism
in it.

The cooling system sat at 15 PSI, rad fan cycled on about 7 times,
engine ran at temp for at least 20 minutes. As I held RPM's higher,
the pressure went down to 12 PSI then "quickly" came up to 15 PSI and
stayed there. Temps at large metal pipe at driver side head were ~
210º F, heads were ~ 250º F

Coolant was bled through the bleed hose at gauge. I should probably
clean the gauge hoses etc. out.

As an aside, I guess if my engine is pumping compression into the
coolant stream, it won't happen at idle. I had seen posts in the
archives regarding the idea of leaving a coolant pressure gauge
connected while driving. I may try this though I'm aware that if an
engine overheat happened, this might cause a part weaker than the
gauge to fail.

If I owned one of those Hero type cameras, I'd take video of the gauge
while driving. (or run a blessedly long hose to front of van)

Neil.

On 5/21/17, Neil N <musomuso@gmail.com> wrote:

> I will report back.
>
> On 5/21/17, David Beierl <dbeierl@attglobal.net> wrote:

>> A gauge for coolant pressure should have full scale reading of at least
>> 20-25 psi since you're expecting readings up to 15 psi or so.  Ideally it
>> should also not be pinned at zero, but able to register negative
>> pressures
>> of a psi or two.
>>
>> If you don't want coolant to be forced into the gauge, use a length of
>> hose
>> between cooling system and gauge, and keep the gauge and hose above
>> system
>> level.
>>
>> Most Bourdon tube-type gauge mechanisms are soldered brass and wouldn't
>> be
>> bothered by coolant.  For digital gauges with silicon sensors, I suspect
>> that resistance to liquids might vary widely but I have no actual
>> knowledge.
>>
>> Yrs,
>> d
>>
>
>
> --
> 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>
>

-- 
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>