What temperare sending unit is this?

[68EFIvert]

I have two sending units on my car. I have one that operates two 9" fans and the second operates the other 2 fans (4 total fans). I originally had one set for 180 degrees and the other was for a higher temperature than that. The first is located in the waterneck and the other is located in the radiator next to the outlet. Anyways, one of the fans comes on later than I wanted so I plan on changing it. I thought the hotter sending unit was in the radiator so I pulled it out. To get to it I had to pull the radiator shroud loose. Once I got it out it had 185 printed on it. I then pulled the one from the water neck and it looks exaclty like the new one I purchased but the top of it is red. The new one (on at 180 and off at 170) is black. Does anyone know if the red top may mean it is a 195 degree thermostat. I will post a picture of the new and old one with my cell phone.

Thanks for the help.

 

[68EFIvert]

 

[68EFIvert]

I think I may have figured it out. I got out the pans and boiled some water. Well almost boiled water. I took my wife's candy thermometer and then checked the ohms of all the sending units. The black one started showing reading at about 180. The red one did not show any change in ohms. The one mounted in the radiator was also showing changes to the ohms at about 180. I assume that the red one is a 195 degree thermostat. It showed readings that started to fluctuate closer to 200.

I put the units back in the car, refilled the coolant and then tried to start the car. Dead battery. I forgot I had a draw on the car that I still need to find. I haven't started it up since mid November. It is now on the battery charger. Next winter I hope to have time to rewire the car.