Re: Aux. Turbo pump checking

[Dave Head <dhead@sundial.sundial.net>]

At 10:36 AM 2/26/97 +0000, you wrote:

>My questions are: Does the thermal switch control the fan also?
Sends signal to after-run relay to turn pump and fan on (low speed).

>Should the fan run at all times when the A/C is on? Mine doeesn't.
Low speed. Common failure of the after run relay. Either that or an open in
yer fan resistor pack. Had both problems.
 
>Should the fan come on also when the temp is above 1/2 scale? Mine 
>doesn't.

Depends on the type of fan control thermoswitch (the one in the radiator).
Stock should come on just under the first little dot on the guage @ about
2/3 scale (medium speed). Above the second little dot, the high speed
(hurricane ops) fan will come on (also comes on due to AC high discharge
pressure). 
I installed a lower rated switch - mine now cycles about 1/2 way. As far as
the after run feature - this is for a HOT car - in the range of just below
the first dot. The fan and pump would come on immediately after shutdown -
possibly a few minutes later if just below the setpoint and radient heat
brought it up slightly.

>How do you know if the fan is running at low speed?
Put yer hand in it (sorry, just had to say this...)  The low speed ops only
occur for after run and AC. The idiot that owned mine moved it to medium
speed on the resistor pack when the low speed resistor failed - caused me no
end of consternation, frustration, and general head-scratching. Low speed is
very quiet - can barely hear inside the car with the window down. Medium
speed you can clearly hear. High speed is somewhat akin to a wind tunnel...

>After my post yesterday I thought that you could put a short section of 
>clear plastic tubing in line with the pump and possibly see if the pump 
>was moving any coolant by observing any small bubbles or maybe the fluid 
>passing through the clear tubing.

Sure - but you could also disconnect it hydraulically, leave it hooked up
electrically, and watch it through the hole with a flashlight.

********************************AUDI FAN***********************************
                                   EMCM(SW) Dave Head  
87 5KCStq 187K miles and counting... 1.7 bar boost - Whee!
                Maitland, Florida   Hey! There's no mountains here!
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