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I'm replacing a mechanical water temp gauge on my 292 and am thinking of also re hooking up the old idiot light, kind of a belt and suspenders thing. I did that on my oil pressure line years ago to help avoid disaster, and figure it would be a good idea for the temp as well.
I have the later style housing, with 2 ports on the pass side- one for heater, other for temp sender. On the drivers side is the large outlet for the bypass. They make a top outlet elbow with a threaded hole on top, but want the sending units on the engine side of the thermostat.
Best I've come up with so far is to 'T' into the heater port and install the idiot sensor there. I have the standard heater without a water valve, so water always flowing in that loop.
Anybody out there have a better idea I'd love to hear it.
Thanks,
Tom