Date:         Mon, 29 Jul 2013 11:57:19 -0500
Reply-To:     Jim Felder <jim.felder@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Jim Felder <jim.felder@GMAIL.COM>
Subject:      Re: Checking pressure cap function???
In-Reply-To:  <51F6760B.8070108@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

I took a bad coolant cap and a short piece of hose and made a tester. It
works fine for what it can do: you simply replace the cap on the waterboxer
with this one, start it up and read the gauge after the car gets warm. But
it doesn't end up telling you anything if the leak is not obvious.

If your car is overheating on hills to the extreme and doesn't want to cool
down quickly; if over the last year or so you have had blown coolants caps
and/or hoses/heater cores, you have leaking heads to some extent. I say
some extent because the symptoms may range from only leaking coolant in
under severe load to spitting coolant out the exhaust pipe.

The gauge I mentioned would be much more useful if the gauge face were
remoted to the cockpit sou you could see it while underway. Then you would
know.

But there are other things you can do. Have the coolant tested for exhaust
gases or buy a kit and do it yourself. Go out in the morning and run the
 car cold for 30 seconds, shut it off and remove the cap. If you hear a
burp when you remove the cap, you've got a leak. But this test will not
tell you if you have the type of leak that only leaks on a hill or under
heavy load.

Basically, if you drive a waterboxer that has ever been really hot, you
have a leak. The head studs can lose their temper, cracks can form in the
aluminum, and uneven overheating can cause the heads to warp. As I recently
found with my diesel, the block is not immune to such sufferings either,
although that would not be a problem on a waterboxer that I can think of.

Jim


On Mon, Jul 29, 2013 at 9:02 AM, JRodgers <jrodgers113@gmail.com> wrote:

> Doug,
>
> My van with it's 2.1L Wasserboxer took to blowing the coolant level
> sensor out of the coolant tank. Had to replace the tank and the cap
> both. Cap because it was bad - the tank because the threads for the
> coolant level sensor were bad.
>
> John
>
>
> On 7/28/2013 6:54 PM, Doug Alcock wrote:
>
>> Hi gang -- I've been blowing hoses on the coolant system ---- is there any
>> way to check if the pressure cap is functioning correctly. My
>> understanding
>> is that the pressure cap should be venting at 15 psi. It is a new pressure
>> cap. I have an 84 Vanagon that has a I4 (1.8 from a VW Jetta) in the back.
>> The Vanagon cooling system remains the same. New waterpump (new engine
>> actually), new thermostat and the rad was replaced about 8 years ago. I've
>> blown 2 hoses since the new engine. I'm pretty sure the system has been
>> bled correctly -- I've been putting coolant into the system from a tiny
>> hose that goes into the front bleeder (highest point in the system) and
>> leaving the highest points in the engine open until they fill -- closing
>> them and then continuing to fill until done. Then I bleed from the front
>> over a couple of days. The temp needle stays where it should, the fan goes
>> on when it should and everything seemed fine until the other day when I
>> blew the top hose on the engine -- which both my I and the machanic who
>> had
>> done the engine agreed looked and felt fine. So I'm thinking the coolant
>> system is creating too much pressure. Hence my request for a way to check
>> if the cap is working as advertised. Grateful for any other thoughts from
>> the fount of wisdom that is this list.
>>
>> Thanks,
>> Doug
>>
>> --
>> http://www.dougalcock.com
>>
>>