Date: Mon, 19 Apr 2010 11:18:03 -0700
Reply-To: Don Hanson <dhanson928@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Don Hanson <dhanson928@GMAIL.COM>
Subject: Re: Over-full overflow tank..cause for alarm?
In-Reply-To: <4BCC9BCF.4020402@charter.net>
Content-Type: text/plain; charset=ISO-8859-1
Thanks everyone... I ordered a new expansion tank cap and my hose is a bit
crummy. I will replace that as well..sounds like exactly what I am seeing.
Also, new thermostat going in....just because...
Don Hanson
On Mon, Apr 19, 2010 at 11:07 AM, John Rodgers <inua@charter.net> wrote:
> Don,
>
> Varying road conditions will result in variations of the temp needle
> position. I seem to have read somewhere that the pressure cap is set at 1
> atmosphere - which is essentially 15 psi at sea level. Expect any change in
> altitude to result in migration of coolant from the expansion tank to the
> overflow tank. If the pressure cap is working properly and there are no
> leaks or holes in the tubing between the expansion tank and the overflow
> tank - then the coolant should be drawn back into the expansion tank as the
> coolant loses heat. While the over flow tank does have high level marks, if
> trouble shooting, it is better to check absolute coolant level by first
> allowing the engine to cool. Coolant should draw down to the bottom mark. If
> not, then there is a problem - assuming the level was correct to begin with.
>
> John Rodgers
> Clayartist and Moldmaker
> 88'GL VW Bus Driver
> Chelsea, AL
> Http://www.moldhaus.com <http://www.moldhaus.com/>
>
>
>
> On 4/19/2010 11:18 AM, Don Hanson wrote:
>
>> My first 'longer' trip in my 84 (with an inline 4 Golf Jetta motor)
>> since
>> around Xmas. I've been driving it, after letting it stand for a few
>> months,
>> for a month now on shorter trips. Everything seems fine, no poor running
>> or
>> power loss, no strange behavior at all...
>>
>> I may be 'gunshy' now or perhaps overly-concerned for no real reason but
>> when I first got this van, I caused myself some extra work because I was
>> unfamiliar with the WBX cooling system. I didn't get a proper air-bleed
>> after flushing the coolant for new..This resulted in some odd temperature
>> behavior issues that I didn't 'pick up' on until I had damaged my
>> headgasket. I had to replace the headgasket on the I-4 motor, no big
>> deal..about 3-4hrs only, but I could have done BIG harm if I'd ignored
>> it...thanks to the list I caught it in time to avoid major damage..So now
>> I've learned to pay close attention to how my WBX cooling system (the I-4
>> plugs almost directly into the stock vanagon 'circulatory system') is
>> behaving.
>>
>> Yesterday I did about 250 miles around Mt Hood going to and from a bike
>> race and I noticed my temperature gauge was reading slightly lower than
>> usual. I put a tank of premium fuel into the van and that is what I was
>> burning on this trip, if that would make a difference.
>>
>> My temp gauge usually reads on or just slightly above the second of the
>> bottom two marks...below that LED. Yesterday I was seeing the needle
>> just
>> above the bottom of those two lines, even when climbing to ~5000'...until
>> I
>> got back to low elevation when I noticed it back nearly to where it always
>> has been...Some fluctuations in the reading...Not a fluttering of the
>> needle, the gauge looks to be operating normally...but the needle would
>> move, over a 10-20min period from quite cool to where it normally has run
>> and maybe fall again...So my gauge is showing 'system running very
>> slightly
>> cooler than normal'
>>
>> When I got home I went back and opened the license plate to check my
>> coolant overflow tank level. It was over-full and poured out about a cup
>> of
>> coolant when I removed the cap...So I opened her up to check the pressure
>> tank...No air in there. The coolant looks normal, also..no combustion by
>> products are evident. Water pump feels fine, though I didn't take off the
>> drive belt and spin it...Next, I went to the air bleed screw in the rad.
>> It
>> took about a cup of coolant, added right into the bleed screw hole, as
>> I've
>> devised as 'my' method of getting the last air bubble out of my radiator.
>>
>> So what would cause my coolant to 'migrate' from the pressurized cooling
>> system into that overflow tank? and should I be concerned? It's not
>> running out of the Normal temp range, but pretty close to 'too cool'...
>> any
>> change in operating temp is alarming to me, since when my first problem
>> happened, the symptoms were 'cold air from the heater' and the temp gauge
>> behaving quite erratically...
>>
>> Don Hanson
>>
>>
>>
>>
>
>
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