where do you tap in for the autometer water temp gauge on the 85 13b???? what size is that small port behind the water pump?? is it a different size on a 12a water pump housing?

 

anyone running autometer water temp gauge??

 

behind the water pump....the hardest part is finding the right bushing. And No, 12-A and the old 13-B are the same size.

If you cant find it, your other option is to tap it on the t-stat cover, and use a 90* fitting. Remember that some of the pre-RX-7 t-stat cover came pre-tapped.

 

In the picture below, you see the Waterpump assembly. From Factory, it has two sensors that work with the engine, ECU, emissions, and Choke systems.

From what I understand, the stock ones usually go to ****, and it makes very little difference (if any) to remove these stock sensors on any FB with any kinds of mods.

The stock sensor for the engine temp gauge (in the instrument cluster) is on the engine block (under the oil filter).

In this picture, I removed the waterpump, and drilled and tapped the top sensor for the Haltech Coolant sensor. The Lower sensor, I drilled and tapped with 1/8 NPT thread, so it fits the Autometer water temperture gauge. It is an electrical gauge and only uses 1 wire to the gauge.

This is the best place to put the sensor, and you don't have to worry about leaks. It should also give the most correct reading since it is on the engine side of the thermostat.