Date: Mon, 22 Aug 2011 18:48:59 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Coolant Strangeness
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I suppose one could plug the overflow hose nipple on the blue coolant cap ..
but that's not right of course.
On in an emergency, short term, let's say.
Some other models may use that cap.
there are black caps, and there are ones without the overflow connection.
you want the right blue one.
re Jim's comment ...
he is talking about checking the 'suck back' valve ....and that part fails
too.
What he describes would not check the pressure holding ability of the new
cap.
You'd need a pressure tester device that tests caps for that.
if you tried to do it with your mouth ..
you'd have to get your whole mouth over the larger part of the cap ( towards
the coolant ) and blow harder than 14psi or whatever the rating is. I don't
think most people can blow harder than just a few psi ..
and that's a lotta cap to get ones mouth around !
and let's hope the cap is the whole problem.
I just had a whole go-around with a burst hose ..
.just idling to see if the rad van would come on.
Sure had me wondering why the cap didn't just release pressure ..
either the hose was weak, the cap was holding pressure higher than it
should, or possibly the engine producing more pressure into the cooling
system than would be normal.
Replacing the cap allowed it to run successfully in that case.
there may or may not be a cap tester adapter available for that type of cap.
for the conventional old fashioned cap, like a diesel vanagon uses ..
I have an adapter for testing those, but not waterboxer pressure caps.
They're inexpensive enough ..
that you just find the highest quality one you can ( a trick in itself
sometimes ) and get two.
I'd say they can fail 3 ways probably ..
won't hold pressure well enough -i.e. release too soon.
Hold more pressure than their rating ...i.e. won't release when you need it
to.
and ..the suck-back feature doesn't work,
I've had trouble getting them to thread onto the bottle really correctly too
at times.
other than that ..hey ..they're fine pressure bottle caps ..lol !
Scott
www.turbovans.com
----- Original Message -----
From: "Jim Felder" <jim.felder@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, August 22, 2011 2:20 PM
Subject: Re: Coolant Strangeness
> When you do locate one, even if it is new, blow-test it before you walk
> out
> the door so you will know it works as a one-way valve. I have bought them
> new that didn't work. There is absolutely no way to repair them.
>
> Jim
>
> On Mon, Aug 22, 2011 at 4:02 PM, Tom Rowsell
> <86westy@geoexploits.org>wrote:
>
>> Thanks Scott, of course I have no spare. I suppose plugging the hose
>> outlet on that blue cap is not wise? Is the cap used on any other VW
>> model just in case I find a junkyard ?
>>
>>
>> On 8/22/11, Scott Daniel - Turbovans <scottdaniel@turbovans.com> wrote:
>> > that blue pressure cap ..
>> > is my first thought.
>> > They are not that reliable. One should always carry a spare.
>> >
>> > right now, with no further information or test results..
>> > it sounds like ..
>> > either pressure cap is not holding pressure properly .....
>> >
>> > or cooling system pressure is abnormally high ( such as combustion
>> > gases
>> > getting into cooling system at the heads or head gaskets ).
>> > If you see bubbles btw...
>> > rising to the surface of the coolant in the pressure bottle
>> > ................unless you are in the process of just filling the
>> > coolant
>> to
>> > start with ..........that is not a good sign.
>> >
>> > if you *always* see a small bubble trail there ...
>> > that's really not a good sign.
>> > Have the air space above the coolant in the main pressure bottle
>> > sniffed
>> > with a smog sniffer. If there are excessive HC's there ....it's a
>> combustion
>> > gases getting into the coolant issue.
>> > It should not do what you are descibing at all.
>> > Try the cap first though ..
>> > as it's so easy to do, and they are known to be a bit dodgey at times.
>> >
>> > Scott
>> > www.turbovans.com
>> >
>> > ----- Original Message -----
>> > From: "Tom Rowsell" <86westy@GEOEXPLOITS.ORG>
>> > To: <vanagon@GERRY.VANAGON.COM>
>> > Sent: Monday, August 22, 2011 11:08 AM
>> > Subject: Coolant Strangeness
>> >
>> >
>> >> This is likely an FAQ...I'm on the road and searching is awkward with
>> >> cell phone.
>> >> It seems when I drive for an hour or so at highway speed, and stop
>> >> abruptly (to get gas for example) coolant rushes from the left tank
>> >> into the overflow one on the right, sometimes overflowing that one
>> >> onto the ground. In one instance the dash light began to flicker and
>> >> when I pulled over, the right hand tank was full, and the left one was
>> >> down 1/2 litre or so. It's not overheating, but temperature rises at
>> >> idle after a highway run.
>> >> 2.1 litre, recent (last 6 months) new rad, water pump. There are no
>> >> evident leaks, and oil on dipstick looks clean.
>> >> Any suggestions on what to check?
>> >> The needle is generally parked right at the center of the LED...
>> >> Thanks
>> >> Tom
>> >
>> >
>>
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