Rocket man, take an old cap and destroy the pressure/vacuum seals
inside the cap.You can then pump it up  and read the gauge on the
pump.

BTW this is one of the top 5 spares to carry.

John Meeks
'91 Vanagon MV
Northern Michigan

Vanagon Rescue Squad
www.vanagonauts.com

On Sat, May 5, 2012 at 7:59 PM, Rocket J Squirrel
<camping.elliott@gmail.com> wrote:
>
> Oh, THANK YOU DAVID for increasing the number of things that I will
> worry about.
>
> 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.
>
> For the expansion tank, uh I'll look for the warning signs. Are new
> tanks available?
>
> For the bleeder valve assembly at the front end of the engine
> compartment, mine blew last year and I have this outrageously expensive
> machined block of aluminum replacement. That, at least, should not fail.
>
> 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. The connection between the pump and the
> nipple is less than air-tight and so the gauge on the pump sagged back
> to zero after every stroke. I thought it was showing pressure in the
> cooling system.
>
> And so I'm looking at a couple small leaks from where hoses are clamped
> and wondering how or why I sprung so many leaks.
>
> It wasn't until I loosened the cap on the expansion tank and heard that
> hissing sound that I tumbled to the fact that I had probably been
> putting a lot more than 10 psi into the cooling system. Happy I didn't
> blow a gasket!
>
>
> --
> 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 01:01 PM, David Beierl wrote:
>>
>> At 01:12 PM 5/5/2012, Rocket J Squirrel wrote:
>>>
>>> This can't be good news.
>>
>>
>> Think of it this way...it's time. Just like it's time -- *really* time
>> -- for that H-shaped plastic bomb back by the pressure tank, and the
>> pressure tank itself if it hasn't been replaced already. Since the
>> H-thing is NLA, someone needs to start making up an equivalent from
>> copper tubing or such. There's a metering hole in the middle of the
>> thing, it's not complicated but not totally simple either. For the tank,
>> look for internal stress cracks in the neck area and around the
>> midsection flange. If you can't see through the tank to find the cracks,
>> consider it toast.
>>
>> And when you're bleeding Mr. Quite Rightly after his new radiator,
>> handle the bleeder valve in the engine compartment very very gingerly.
>> That's another plastic fitting that's past its sell-by date and probably
>> NLA.
>>
>> Yrs,
>> d