From: blu@cellar.org (Dan Reed)
Newsgroups: rec.autos.vw
Subject: Keeping Your Watercooled VW cool.
Date: 12 Nov 92 19:30:18 GMT
Organization: The Cellar BBS and public access system


         Project AutoHack #004, Keeping your watercooled VW cool!
 
          For VW Jetta][/Golf, can be modified to fit any other
                           late watercooled VW.
 
Disclaimer - This works fine in my car, its simple, easy to install.
             However, if for some reason, you harm your car, yourself or
             your pride, don't come lookin' fer' me.
 
On a "difficulty scale" of 1 to 10, 1 = Headlamp change/10 = New clutch.
 
       I'd say this is a 3 at most, Minor electrical work at best.
 
Time involved - Installed and working under 40 Min.
 
The Problem - Watercooled VWs are cooled by an electric fan.  This fan
              switches on and off, as needed.  The fan is switched by a
              small thermo-electric switch located in the radiator.  The
              switch "turns the fan on" at about 195 Deg.  I think this
              is too high, I'd prefer my fan to come on a bit sooner.
              APS makes a "new" switch that comes on at 180 Deg.  I just
              don't like the idea of the switch at all, I'd prefer to
              "hardwire" the fan "on" at all times.  However, if I did
              this, the fan would be "on" when my car was "off", thus, it
              would kill my battery.  All the relay does, is act as a
              switch.
               This hack will make your VW run *much* cooler.  I thought
              of it when I was having problems with overheating.  My car
              used to run with the temp gauge at 3/4, now it runs at 1/4
              to 3/8ths.  My cars heat is still fine and warm in the
              winter.  This hack was originally designed for summer use,
              but so far, even with the few cold days we have had up
              north, the car seems to be OK.
 
The Solution - Wire up a simple 12V 30Amp relay to the fan.  Find a wire
               that is "hot" when the car is on (turns fan on), then
               "cold" when the car is off (turns fan off).  One simple
               "hot" wire I found was the ignition coil.  The could
               should have (+) and (-) shown on the "face" of it.
 
               This hack is totally 100% reversible.  No stock parts are
               damaged or modified in anyway.
 
Parts Needed - Wire (12 Ga), Crimping Connectors, 12v 30Amp Relay.
               (Radio Shack/discount auto stores sells all parts needed)
 
Tools Needed - Wire Cutters/Strippers, Cimping tool.
 
Schematic -
 
         -----------
         |         |_____________________________
         |  Fan    |                             |
         | Switch  |(center terminal not used)   |
         |Connector|_____                        |
         |         |     |                       |
         -----------     |                       |
            *1           |                       |
                         |  -----------          |
                         |__| Relay   |__________|
                            | 30 Amp  |
                            -----------
                            |   |__________ (-)*2
                            |
                             \
                          (+) \-----------------------
                              |                       |
                           <<<    Ignition Coil       |
                              |                       |
                          (-)  -----------------------
 
  *1 Connector is located ON the lower right hand side of the radiator on
     an A2 car.  A2 cars have a three pole connector, the center pole is
     the "middle speed" for the fan.  Results work best if the fan is on
     "high" (the two end connections).  Hook up a MALE spade connector to
     the relay wires, and stuff them into the connector, they should fit
     fairly well.  Polarity does _not_ matter.  Check relay instructions
     for proper hook up.
 
  *2 Good solid body ground, or (-) off ignition coil.
 
Happy Motoring.
 

--
Dan Reed AKA Blu Max - blu@cellar.org - AnalCADGeek! - Industrial Music Maker
    68' Cougar XR-7, 89' VW Golf, 74' Honda CL360t, Vextrex Unit Lover
Legal for off-road use only, which may never be used on a highway....