E28 Overheating

[Turbo23dog@xxxxxxx]

Listers, 

       I have a misbehaving 84 533i.  The car will go from stone cold to 
overheat in just about 5-10 minutes.  There are no obvious leaks anywhere.  
The coolant warning light on the overhead console is lit even when the 
coolant tank is filled to capacity.   I checked Bentley for tips; boiled the 
Tstat ...it opened at ~175F like it should.  Also replaced expansion tank cap 
with new from BMW; no help.  The car had a new radiator, hoses, Tstat and fan 
clutch about 1 year ago so all that's good.  

 I can feel the upper rad hose get hot but the rad stays pretty cool so I 
don't think any coolant is circulating.  The low/high speed fans don't come 
on even though coolant is puking out the overflow hose and the temp gauge is 
in the red.  I checked the low and high speed fans by bridging the wires to 
simulate closed and they work but I don't think the rad is hot enough to 
cause the switches to close. 

Bentley says that water pumps rarely "totally" fail but I can only conclude 
that is what what has happened.  Any ideas? 

Not too Cheery,
Rich Franco
Burke,VA
1984 533i  
5 sp w/101K miles
Burgundy/Black interior

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