<VV> Stewart Warner Head Gauge Question

[Sethracer at aol.com]

In a message dated 8/18/2009 8:10:31 P.M. Pacific Daylight Time,  
bgilbert at redshift.bc.ca writes:

I assume  they represent a connection to ground through the ring which I'm
guessing  is a variable resistor that reacts to the heat. Is that  correct?


Simple question - does the second wire need to be  replaced? 

Regards,

Bob




No, Bob. Because what you have there is a thermocouple. The two dissimilar  
wires are crimped to the tab on that ring. Where the two wires meet, the  
junction of the two materials create a small current, that is proportional  
to the heat applied to the junction. The gage reads that small current and  
displays it as the temperature of the junction. All you need to do is strip 
both  wires and crimp them onto another ring terminal. The gage should 
function as it  did before. Unless you really want to fool around with a ring 
under a spark  plug, you should crimp on a 3/8" ring terminal and, using a 
short, socket-head  screw, mount the ring terminal into the hole on the other 
head that is  normally occupied by the temp switch (on the 110/95). If you have 
a 140, the  hole may already be occupied by a switch or thermocouple for 
the Corsa dash.  Unless the original thermocouple is already broken (pretty 
common) you  should not try to remove it. I have about a 20% success rate. 
Usually the outer  shell breaks off, resulting in a lot of work. If it is 
already broken? What the  heck! The 110/95 heads have a coarse thread in this 
hole, the 140 and 180 heads  use a fine thread.  

 
Seth  Emerson

C's the Day! - Corvair, Camaro,  Corvette