Re: typ44TQ radiator fan question

[Wallace White <wallace@remdesign.com>]

Chris and Jack -

There are a few things that could cause this:

(1) 1st stage radiator relay or resistor (more likely?) not functional.

The after-run relay turns on the first stage rad. fan relay, not the
second stage fan relay that is used while driving. The first stage fan
relay is also used when the A/C is on, so the quick check on this point
is, does your rad. fan come on when the A/C is on?

(2) after-run thermoswitch not closing when hot.

The after-run relay uses its own thermoswitch to run things, not the same
sensor that triggers the fan while the engine is running. It closes when
hot, opens when cool.

(3) after-run relay not working

Try shorting the thermoswitch contacts to bypass the thermoswitch; you
should hear the rad. fan and after-run pump come on.

HTH!

- Wallace
  '87 5kcstq 156k

> on my '86 5kTQ, the rad. fan does not come on, after the car is shut off, 
> while hot.  for example, the rad. fan is running while the car is on, but 
> when i shut the ignition off the fan doesnt even go to a lower speed like it 
> should, and keep running, it just shuts off completely.   the only thing that 
> continues to run is the injector blower fan that blows air up over the valve 
> cover to the injectors.  any idea as to why the rad. fan doesnt cycle on and 
> off after shutdown, but only runs while the ignition is on?
> 
> while the ignition is on, the fan works fine, and cycles on when needed.
> 
> TIA-
> chris
> '86 5kT, TQ