<E30> Fan clutch

[Mark Holbrook <holbrook@xxxxxxxxxxxx>]

If you had an E30-M20 that was overheating, and you'd already discovered
the broken (closed) thermostat and replaced it, and flushed the radiator
(and noted the good flow through it), and changed the coolant, carefully
bleeding the system, and checked out the auxiliary (electric) fan and
its sensors, and it still ran hot, and then you noticed that the fan
(with the viscous coupling) turned about as easily when the engine was
hot as it did when it was cold, the next thing you'd do is replace that
fan (or coupling), leaving the last possible culprit, the water pump,
for last if the replacement fan (or coupling) didn't cure the problem,
right?

Why do these things (viscous couplings) go bad?  Is it stupid to try to
find one in a junkyard?  Why does my Bentley manual say (paraphrasing)
"Don't lay the fan down on its side?"  Does the stuff ooze out if you
do?  If I have one shipped to me, how can it possibly not spend at least
some time on its side during transit?

TIA for any or all enlightenment.

- -- 
Mark (Holbrook@domain.elided)                    "Back roads. Period."
http://www.net1plus.com/users/holbrook/mark.htm

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