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rotorwrench · 08-20-2010, 06:09 PM

There used to be several part numbers for the single terminal temp bulb that is installed in the passenger side head. After more than 50-years they get mixed and matched plus the aftermarket types get slipped in there. It is the one that actually is calibrated to give the gauge a temp reading. The twin terminal bulb in the driver side head is just a thermal on-off switch so if it gets hot enough to trip the bi-metalic switch, it just goes straight to "Hot". For piece of mind, it wouldn't be a bad idea to rig yourself up a test set up with a hot plate and a thermometer that can be trusted.

Kerby

08-20-2010, 06:09 PM	#3
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,509	Re: radiator water temp vs. head temp There used to be several part numbers for the single terminal temp bulb that is installed in the passenger side head. After more than 50-years they get mixed and matched plus the aftermarket types get slipped in there. It is the one that actually is calibrated to give the gauge a temp reading. The twin terminal bulb in the driver side head is just a thermal on-off switch so if it gets hot enough to trip the bi-metalic switch, it just goes straight to "Hot". For piece of mind, it wouldn't be a bad idea to rig yourself up a test set up with a hot plate and a thermometer that can be trusted. Kerby