Date: Tue, 13 Sep 2005 13:52:25 -0700
Reply-To: Evan Mac Donald <macdonald1987@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Evan Mac Donald <macdonald1987@SBCGLOBAL.NET>
Subject: Re: Cooling system questions for 1.9L
In-Reply-To: <OFA3D41266.1753A79C-ON8525707B.006FD6A0-8525707B.0070B164@fairchildsemi.com>
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Howard Allen <Howard.Allen@FAIRCHILDSEMI.COM> wrote:
Wish I had an aircooled but since I don't I would like to get as much
information about my "new" watercooled baby. Talking with a long-time
1.9L VW van owner the following opinions were expressed. Would appreciate
the List's feedback.
1. The fan sensor switch is too low in the radiator to do a good job
preventing overheating during low speed travel [therefore install a manual
override switch]?
2. The water pump does not flow enough coolant during idling in stop and
go driving [this guy installed a smaller pulley onto the waterpump shaft -
is this recommended?].
3. Radiator cooling capacity is insufficient during high ambient temps
while endeavoring to climb 7% or greater grades [therefore install a
larger radiator]?
4. Highway speeds of greater than 65 MPH will result in headgasket
failure caused by overheating?
5. The factory temperature guage is not a reliable indicator of
dangerously high coolant temperature - anything past half way actually
indicates an over temp condition that should be addressed by pulling over
and shutting down the engine immediately?
Best Regards
Howard Allen
S. Portland, Maine
"Don't tread on me."
O.K. Howard, let's try to dedal with these in order of asking.
#1. Nope. The fan switch sees what the coolant temprature headed back to the engine is, because it is nearer the return line. That is just where it needs to be to do its job best.
#2. Nope. NOT reccommended under just about any circumstances. MAYBE if you delivered mail in it, and never went above about 2500 rpm. With a smaller pulley, you will be spinning the pump too fast at any sort of cruising rpm, and causing things like cavitation to occur. Then , when the engine is running faster, under more load, and needs more coolant flow, it won't get any.
#3. Nope. There is enough capacity in this stock radiator (when in good condition) to cool a small block V-8.
#4. Nope. Unless the rest of the cooling system is trashed, 65 mph is not enough to kill your WBX. 85 mph, maybe, but not 65.
#5. Nope. Unless there is a fault elsewhere - bad grounds at the engine or in the insrument cluster, or an incorrect sending unit, the gage is accurate enough to be believed.
Evan Mac Donald
1984 Wolfburg
1985 GL 7 Pass.
1991 Carat Weekender