My guage is broken, where is the sender on a 79 SA?

 

in the rear iron below the oil filter.

 

hmm...strange...

I have two sensors coming out of my 1980 rad. One is on the top middle (level sensor?) and the other is driver's side near the cap. I thought that was the temp sender?

 

Ok That is strange. The other night I broke the only belt and my water temps started going down. I thought the sensor must be in the rad or water pump housing. If it is in the rear iron why would my temps have started going down with the water pump not working?

 

Because hot water was no longer flowing through the engine. It was just sitting at the 'hot spots' of the engine while the rest of the engine's heat was going down through convection with outside air, the heat-sink nature of the aluminum bellhousing, the rotation of the flywheel with its built-in counter weight (yes, air does move inside the bellhousing when the flywheel spins), oil cooling still functioning (it enters at the rear plate) etc. All contribute to cooling the rear plate adjacent to the temp sensor. Of course, this is all just a guess.

 

What the best way to see if it works then?

 

Unplug it and see what the guage does. Mine goes to hot when the key is turned on if the sensor is not connected.