"So unless your pressure cap is completely out of spec you were not over
pressurising the system. Totally how it was meant to work."

Interesting. There was a considerable amount of hissage* when I loosened
the cap on the expansion tank. And a couple joints in the coolant lines
were dripping. This is a dark-blue cap that Mark Drillock had been kind
enough to gift me when I lived near the man.

--
Jack "Rocket j Squirrel" Elliott
Bend, Ore.
1984 Westfalia. A poor but proud people.
1971 "Ladybug"-brand utility trailer ca. 1972 from a defunct company in
San Clemente, Calif., now repurposed as The Westrailia.

On 05/05/2012 05:59 PM, David Beierl wrote:
> At 07:59 PM 5/5/2012, Rocket J Squirrel wrote:
>> Oh, THANK YOU DAVID for increasing the number of things that I will
>> worry about.
>
> Only too pleased to be of service <removes plumed hat and sweeps low bow>
>
>
>> The H-shaped "plastic bomb" thing -- I sure hope someone comes up with
>> a replacement part so I can just swap it in before mine blows. With my
>> luck the thing would decide to blow when I'm in the backcountry and
>> out of cell phone range.
>
> I sure hope so as well. Fortunately the 2.1l haven't got one, though
> they have their own plastic nightmares. My unchecked thought is that
> anyone who can sweat-solder ought to be able to run up a onesie given a
> sample to work from; but things always seem easier when you haven't
> looked at dimensions and such.
>
>
>> For the expansion tank, uh I'll look for the warning signs. Are new
>> tanks available?
>
> Yes. Pretty cheap, too.
>
>> Say, BTW, I followed your suggestion to pressurize the cooling system
>> with a bicycle pump. I didn't know that the nipple on the expansion
>> tank's cap was a one-way device.
>
> 'Tisn't It's two zeners in parallel with opposite polarity. The one you
> were pushing on has a breakdown pressure of ?half a pound? and the one
> facing the inside of the system has a breakdown pressure of around
> thirteen pounds. That's why and how the coolant gets into the overflow
> bottle in the first place, and how it gets sucked back when the system
> cools. So unless your pressure cap is completely out of spec you were
> not over pressurising the system. Totally how it was meant to work.
>
> Yrs,
> d
>
>