Date: Wed, 14 Oct 2015 23:21:15 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Missing coolant
In-Reply-To: <1D564C1E-F579-482B-8081-56364CDC5E0D@EricWunrow.com>
Content-Type: text/plain; charset="US-ASCII"
There are a few different cap designs out there. Most rely on the valve
piece being sealed to the cap when it is secured on the tank so the simple
mouth test may not be reliable. They rely need to be tested in place with a
gauge set up so you can confirm the opening pressure. Since the Vanagon uses
the closed system approach with the recovery tank once the system is
completely air free, the cap has to release every time engine temperature
increases. On system that have an air pocket under the pressure cap the
system only has the cap vent during an overfill or overheat condition.
While I have seen bad caps, they are usually obvious at installation. Once
tested good future failures are a symptom. Usually overheating or excessive
over pressurization is the reason for failure. Look for the melted parts or
damaged seals. Cracked or loose heads.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Eric Wunrow
Sent: Wednesday, October 14, 2015 3:36 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Missing coolant
I'm a total rookie compared to you guys, but wanted to note I've had at
least three expansion tank (blue) cap failures in 23,000, full-time miles
over 26 months on the road. I believe the failures are somewhat related to
how many heating/cooling cycles they're asked to do.
I only buy the German ones, and my test is if you can both suck and blow on
the cap, it's toast (please keep the jokes to yourself).
My understanding is the cap should only release pressure one direction - not
two.
Eric
Eric Wunrow Pictures
303. 988. 8717
VW@EricWunrow.com
On Sep 28, 2015, at 3:27 PM, Stuart MacMillan <stuartmacm@GMAIL.COM> wrote:
> Thanks Jim, the cap was replaced with an OEM cap when the water pump was
done 13,000 miles ago, and the overflow tank doesn't show any evidence of
any spillage on or under it. I'm thinking small leaks too, but I'd like to
narrow it down. The 2.1 has a lot more hoses than my 1.9!
>
>
>
> Stuart
>
>
>
> From: Jim Felder [mailto:jim.felder@gmail.com]
> Sent: Monday, September 28, 2015 2:21 PM
> To: Stuart MacMillan; vanagon@gerry.vanagon.com
> Subject: Re: Missing coolant
>
>
>
> Old hoses leak microscopic amounts of coolant. Ive had it spray onto the
engine in such small quantities that it would evaporate before you could see
it. Tighten hoses, replace hoses is about all you can do. But you didn't
mention testing the pressure cap. That can send a good deal of coolant into
the expansion tank, which can drip on the road through the overflow and you
won't know it.
>
>
>
> Jim
>
>
>
> On Mon, Sep 28, 2015 at 4:11 PM Stuart MacMillan <stuartmacm@gmail.com>
wrote:
>
> Just when everything seems to be sorted out, it isn't. Son's '87 is
> losing over a quart of coolant every 400 miles, and I can't find any
> leaks. Rear heater has been removed, and there is no odor from the
> front heater. No drips anywhere-engine plumbing, heads, transmission
> cooler, radiator, or front heater valve. No evidence of coolant
> mixing with either the transmission fluid or engine oil, and that much
> coolant would certainly foam oil.
>
>
>
> I'm wondering if it's burning coolant, but in my experience failed
> sealing rings in Vanagons lead to over pressurization of the system,
> and that's not happening. It also runs great. I sometimes notice a
> faint smell of burning coolant at the engine compartment vents, but I
> can't find anything dripping on the exhaust when the system is
pressurized.
>
>
>
> Would investing in a UV leak detection kit tell me anything? It would
> seem losing this much coolant would show up somewhere.
>
>
>
> Any ideas?
>
>
>
> Stuart
>
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