Date: Tue, 2 Sep 2003 07:03:04 -0400
Reply-To: 72510.1173@COMPUSERVE.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Helen Fahy <72510.1173@COMPUSERVE.COM>
Subject: Re: Wierd coolant overflow problem......help needed.
Content-Type: text/plain; charset="iso-8859-1"
Hi Adam,
I had a similar problem a couple of years ago. In my case it turned out to be a crack in the expansion tank located on the coolant level sensor boss. It was not obvious at first but there was a trace of coolant solids around the sensor, and no liquid. The liquid had evaporated off as that is one of the hotter areas under the decklid. The crack would, as the van cooled, prevent the system from holding a vacuum and drawing the expanded coolant back into the expansion tank from the overflow tank. The crack would allow some air in the expansion tank every cool down cycle resulting in a growing air bubble in the expansion tank
HTH.
Joe & Helen Fahy
'87 westy
----- Original Message -----
From: Vanagon Man
To: vanagon@GERRY.VANAGON.COM
Sent: Tuesday, September 02, 2003 5:59 AM
Subject: Wierd coolant overflow problem......help needed.
Folks,
I am working on this 90 van. At first when i got it, the needle ran about 3/4 of the way on the gauge, and the level indicator would blink...........it seemed the coolant was low.............
First thing i did was test for exhaust gasses in the coolant using a Snap On tool i have. None present. Previous owner had had the system pressure tested, and said no leaks. I replaced radiator, lower temp thermoswitch for fan, ballast resitor for fan, and lower temp thermostat, new pressure cap. Needle still ran 3/4..............checked temperatures with infra red tool, and seemed lower than that. So swapped sender for the gauge, and now it runs right at the red dot as most vanagons do.......traffic and long stops make the needle creep up, but it always comes right back down once you get rolling.
But there still is a wierd problem. It seems that the pressure cap allows coolant to leave the system into the overflow, but it does not suck it back in. So, if you have the overflow filled to max, after a drive you look at the overflow and it is 1 1/2 " higher than high, and the regular expansion tank ( the one with the fitted pressure cap) has a good sized air bubble in it. I have bled the system more than once, and this same thing keeps occuring. Tested again for exhaust gasses, none present, and no coolant leaks on this vehicle.
Any ideas?
Adam P
81 Vanagon Westy (The Brick)
70 Single Cab "Whitey" (finally on the road)
74 Beetle "Ol Yeller"
73 Transporter (STILL at paint shop)
1988 Vanagon Wolfsburg
Used Vanagon Parts for sale (mostly aircooled)
|