Inliners International Forums General Discussion Engines 292/250 Engine Temp Question

Hi Newcomer.

I have a question for you.

I have 1979 with a 250 and intergrated head. My temp probe sender is in the water-neck up front along with two TVS's (thermal vacuum switches). The temp probe sends to the orignial dash temp. gauge.

My question is I have another probe with a wire
between the # 5 and # 6 cylinder. It has what might be a 1/8" pipe thread, to thread into the head. Do you know what the function of this sending unit is?

Thanks.
EV