TedH

My 1/2" NPT temp sensor on my 1980 L48 has finally broke (single blade on top broke off). I suspect this may have had something to do with the elevated tem readings I've been getting; regardless, it has to be replaced.

I see in the Zip catalog that two different one-blade temp sensors are listed for the 79-80 (L82, A/C) and the 81-82.

The 79-80 is the 1/2" NPT sensor while the 81-82 appears (in the picture) to be a 3/8" NPT sensor. As stated, both are 1-blade sensors:

PN# 303160 = 79-80 Temperature Sensor-L82 w/AC, $27.25

PN# 303161 = 81-82 Temperature Sensor (1 Blade), $28.75

Common sense tells me to get the 79-80 sensor (I have an '80 L48) while I'd really like for the 81-82 sensor to 'work' since I don't have a good location for the 1/2" NPT sensor. I have had to locate it directly under the upper radiator hose at the thermostat housing. I had to bend the sensor blade horizontal/flat to clear the hose and suspect that had something to do with the blade breaking off.

My preference is to locate the 81-82 sensor in the cylinder head where clearance isn't an issue (and the blade can be straight out from the base of the sensor like it was designed). If not, my next choice is to place the sensor in the thermostat housing (I have two plugged holes there where I removed the thermal sensors that drive EGR, EFE, or PCV, etc.).

As I mentioned, both are 1-blade sensors and only 1 year apart in application.

Advice welcome!

:seeya

KenSny

The differences are more than the "hole/thread" size. Various sensors have different resistance (ohms) readings at different temps. Unless you have the temp gauge from (for example) a 79, AND the sensor, you will probably not be happy. The gauge in a '75 (for example) will not record the temps correctly even if you use an adapter to reduce from 1/2 to 3/8 NPT.

nearflack

I have a 1980 L-48. I think the current sensor is bad as the gauge tests good. The current sensor has a "button" connector and all I find as a replacement have the blade connector. The sensor wire appears to be factory and has the button connector on it. The only sensors I find with button connector are for older model C3s. Do I use an older sensor or get the one with the blade and change the end on my wire.

stingr69

There are guage temp sensors and aux radiator fan swich sensors. Make sure you order the right one.

derekderek

inside the thermo hsng is the wrong side of the thermostat. i think eckler turns the 1/2 inch ones down to 3/8ths pipe. otherwise use the plug next to the thermo housing in the crossover on the front of the intake. and if 3/8ths, there is usually enough meat to drill-tap it to 1/2 npt. pipe is a tapered tap. crank it too far in and you will need 10 feet of teflon tape to make it seal.

carriljc

nearflack
You probably should have started a new thread since this guy was from ages ago..... I responded before noticing....but anyway, is your hole 1/2 or 3/8 NPT.... if it is 1/2 then change the lead to a blade connector and then---
Just go to willcox and get the sensor they recommend and the adjustable resistor to dial in your gauge. I lived with that inaccurate gauge for years and then finally bought the adjustable resistor and dialed it in. The adjustable resistor worked great on my 68 gauge.

https://willcoxcorvette.com/79-80-te...e-sending-unit
https://willcoxcorvette.com/corvette...resistor-77-82

If you're confused then give them a call.

vettebuyer6369

You are responding to a thread from 18 years ago.