At 05:15 PM 1/7/2012, Evan Mac Donald wrote:
>All right volks - I have two thermostats that I 
>am attempting to test. One is still installed in 
>the t-stat housing, but the housing is off of 
>the engine. The other is a 
>brand-new-from-the-box Wahler. Both are 87� C. I 
>am trying to check them, using the hot water 
>method. The problem is that I am not seeing any 
>difference in either one, from cold, to hot (93� C),

The standard thermostat should start to just 
barely move at about 85C and must open at least 
8mm by 105C. (Bentley 19.8). Heat it in coolant 
mix or oil and you'll be able to get up to 105C 
ok.  If there's seriously no motion at all by 93C 
I would call that a problem (possibly in your 
thermometer, though.  Vigorously boiling water 
will give you a decent endpoint at 100C corrected 
for altitude if need be. Are you at 7,000 
feet?  If so I'd definitely go to coolant or oil).

Yours,
David