Date: Mon, 19 Apr 2010 14:55:56 -0500
Reply-To: John Rodgers <inua@CHARTER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Rodgers <inua@CHARTER.NET>
Subject: Re: Over-full overflow tank..cause for alarm?
In-Reply-To: <r2w6bc66ccf1004191118kc5520637jc2ac98e7d3cbae4b@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Be careful of the source of your new thermostat. Some fit, some don't,
even though the parts catalogs say they will. Just kinda like oil
filters - catalogs say their brand(whatever brand it is) is made for the
Vanagon - but it doesn't work. Mahle and Mann are the best - though
there are a couple of others that may work - same with thermostats - but
most don't.
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com
On 4/19/2010 1:18 PM, Don Hanson wrote:
> 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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