Date: Sun, 28 Jul 2013 20:58:06 -0700
Reply-To: Scott Daniel <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel <scottdaniel@TURBOVANS.COM>
Organization: Cosmic Reminders
Subject: Re: Checking pressure cap function???
In-Reply-To: <CAP0ZLPRyJsbfvbJayP7t0QE8-zAnR1pJvohZqOEKvCbk4tNzDQ@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I would either make a pressure testerfor your cap ..
or try another cap.
I have seen many vanagon pressure caps not release pressure when they
should.
I always carry a spare ..they can not hold pressure, not release
pressure when they should ..and not suck backfrom the license plate
bottle - 3 failure modes.
It's very interesting to run a cooling system pressure gauge ..
in the cockpit where you can see it at all times driving.
I wouldn't think it should get over 20 psi even if the cap doesn't release.
consider that it may be combustion pressure getting into the cooling
system..
head or head gasket usually.
I've seen that syndrome so bad, combined with a non-releasing cap ..
that the pressure bottle was puffed up like a ballfrom the pressure..
and brand new high quality one .
Scott
On 7/28/2013 4:54 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
>
