Allo Mes Amis,

My '85 westy seems to be running hot these days when I'm stuck in rush hour
traffic or if I let her idle at the curb.  It seems strange that the
radiator fan doesn't want to come on until the temp gauge has climbed up to
about 7/8 at which point it cycles on/off at low speed.  I don't believe
that I've ever heard it go up to high speed - though the high speed circuit
does work when i short the aproppriate wires.

I've recently replaced the thermostat and flushed the entire system, but
neither action had any effect.  My latest suspect is the fan thermoswitch.
Thus raising the following questions:

1) Do these things tend to go bad?
2) I'm guessing that these things are some sort of bimetalic switches that
rely on heat expansion?
3) Is there anything particularly bad about shorting the low-speed fan
connection semi-permanently (or at least until I can get around to getting a
new switch)?  Particularly, I noticed that the fuel injection system uses a
temp sensor near the water pump.  I assume this is to make the mixture
richer when the engine is cold?
4) Is there any problems associated with using the the thermoswitch from the
86-91 models which seem to have lower temp ratings?

thanks,
wade