Wierd UrQ cooling issues

[Michael Williams <urquattro@surfree.com>]

hey all, just had a wierd problem with my cooling system.  Actually, ive 
had it since i first got it.

Well, the heater valve is leaking, badly, but that is on order from 
carlesen...

But here is the thing.  I have an aftermarket VDO water temp guage, and 
if the water temp goes above 180 or so, the coolant tank boils over.  It 
spurts steam and coolant all over the place.  Its pretty irritating.  I 
know that 180 isnt all that hot, heck, its not even boiling yet....

Anyone know of a way to check the accuracy of this guage, or maybe temp 
sender?  Could this be something that would be caused by a bad coolant 
bottle cap?  It supposedly has a new one from december....

Also, it cant maintain a cool (on my guage, about 150 degrees) unless i 
manually turn on the radiator fan to high speed.  I do so by turning on 
the "A/C" which on my car, has been deleted, but it still turns on the 
fan.  Anytime i stay still in the car, the coolant temp steadily rises to 
above 180, and proceeds to boil over unless i physically turn on the fan 
to the high speed setting, then it will cool down and maintain the 150 
degree temp...


Its pretty irritating.  Anyone have any input?

later...

Michael Sheridan Williams
ICQ# 11740998
1983 UrQuattro, MC--1.8 BAR, borla, 16x7.5 OZ Mito's w/ SP8000's, K&N
1985 4000S Quattro miles, Koni Yellows/Coilover (2B), strut brace, Sport 
8000 Tires, K&N
http://members.aol.com/daserde2