Temperature Sending Unit

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Mango

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Here I go Again
Temperature Gauge reading Low, old one would read just below 210 then it would no longer read above 120 might have something to do with accidentally spraying some PB Blaster on it when preparing to remove the O2 sensor OOPS
Installed a New Temp Sensor it had some teflon tape on it, Now Gauge reads just above 210?
What is the normal temp on these old 350s with a 195 thermometer
89 Burb with 197,000 miles
Thanks
 

HotRodPC

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These gauges are not perfect. If you have a 195 and it's reading at 210 then I'd call it good. You can pretty much forget the #'s on these gauges. They're a ball park. You can use the needle as a benchmark, or KNOW what's normal. So if it's reading a tad over 210 now and it's not overheating, then that's your new normal. So now you know if it goes over that, then you know it's running warmer than normal or HOT.
 

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I agree, the numbers on the gauge don't really need to be there. Learning the needle position is what matters. If it were a clock with only an hour hand - Mine would run at 12:00 and go as high as 12:30. I flushed the system and changed the fan / shroud design, and clock went down to 11:00 and stays there all the time.

Also, for about $13 you can get one of these on Amazon, so that you can see what the gauge position actually means:
 

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Mango

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@Edelbrock I have a Temp Pointed at the Temp Sending unit read 150 ish Would that be a good Location to check?
 

Edelbrock

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@Edelbrock I have a Temp Pointed at the Temp Sending unit read 150 ish Would that be a good Location to check?



Its best to take multiple readings from different parts of the engine, but you want to stay away from the exhaust manifolds / headers.

What ever area gives you the highest reading is the most accurate temp. The inlet of the radiator, various spots on the intake manifold, front of the heads, etc. Doesn't hurt to take a temp reading on the bottom of the oil pan, just for a more rounded picture of the overall engine temps.
 

fast 99

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After it's been running for a time thermostat housing or the area near stat on intake. Reading will be slightly lower than actual coolant temp.
 

Ricko1966

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Here I go Again
Temperature Gauge reading Low, old one would read just below 210 then it would no longer read above 120 might have something to do with accidentally spraying some PB Blaster on it when preparing to remove the O2 sensor OOPS
Installed a New Temp Sensor it had some teflon tape on it, Now Gauge reads just above 210?
What is the normal temp on these old 350s with a 195 thermometer
89 Burb with 197,000 miles
Thanks
You do not that all the senders are not the same. They vary by year so your sender needs to match the year of your gauge. You can tell the correct sender by reading resistance values. I do not have them memorized. Found it for you.
You must be registered for see images attach
 

xm20k

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The stock gauges in these trucks are far from accurate and are just more of a heads up when something is a bit off so to speak.
 

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Temp Sensor should NOT have Teflon tape on it. Remove the sensor, clean the threads and put some copper anti-seize on them. For the sensor to work it needs a clean shot to ground.
 

AuroraGirl

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Temp Sensor should NOT have Teflon tape on it. Remove the sensor, clean the threads and put some copper anti-seize on them. For the sensor to work it needs a clean shot to ground.
a dab of liquid thread sealer is fine.. but they should be taper fit pipe thread.. no? The sealer would be to prevent seizing and incidental liquid maybe

i just wouldnt want copper antiseize near the coolant
 

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