<VV> TEMP/TRESS Light

[Sethracer at aol.com]

In a message dated 5/13/2010 10:13:30 P.M. Pacific Daylight Time,  
nicolcs at aol.com writes:

No, the  temp sender is not on top. It's underneath and inside  the right
lower  air duct, screwed into the cylinder head. It's nestled between the 
two
push  rod tubes for cylinder #1. Open the damper door and you'll see the
wire.  

Two switches (oil and temp). Either can operate the light. Both  are
reliable. The oil switches are very reliable until someone uses  anything
other than the weirdball, non-standard socket to tighten one. The  special
socket is available at most any  FLAPS.






The warning light can be turned on in three ways, really two modes. When  
you turn the ignition on (before starting) the light comes on because the  
voltage through the light bulb goes to the back of the car and to the  
terminal on the "pressure switch", since the motor is not running, no pressure  is 
present and the (normally closed) switch is grounded, turning on the light.  
Since the engine is cool (not over-heated, at least), the snap switch 
remains  open and no ground occurs there. When you start up the car, the oil 
pressure  lifts the pressure switch off ground and the light goes out. If you 
lose oil  pressure, that switch will ground and turn on the light. If you toss 
the fan  belt and the engine heats up (the charge light should come on as 
soon as the  alternators stops) eventually, the high head temperature at the 
temp switch  will close the switch and turn on the Temp-Press light. The 
third way for the  light to be turned on is for either the wire to the oil 
pressure switch or the  head temp switch to be grounded mechanically, a broken 
terminal, cracked wire,  other things could ground it as well. By the way, 
the oil pressure switches  are a 1/8 NPT thread. It is recommended to NOT use 
teflon tape sealer on the  switch or fitting threads, because that can 
isolate the ground path through the  tapered threads. That ground path is needed 
to turn on the light. The most  common failure mode for the oil pressure 
sender is leakage, not failure to  ground. As Craig said, the proper socket 
should be in every Corvair owners  toolbox. Cheap insurance. Any excuse to buy 
another tool! 
 
PS - I always preferred TEMP/TRESS light. 
 
 
Seth  Emerson

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