Coolant Temperature Sender

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Bob Weir
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Re: Coolant Temperature Sender

Post by Bob Weir » Mon Sep 09, 2019 8:49 am

Have you used an infrared thermometer to read the temps at various locations?

Reference https://blog.thermoworks.com/tips/infrared-thermometry/

brokencase
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Re: Coolant Temperature Sender

Post by brokencase » Tue Sep 10, 2019 11:42 pm

When you say the reading is on the "high side of normal" what exactly do you mean?

john keefe
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Re: Coolant Temperature Sender

Post by john keefe » Wed Sep 11, 2019 1:46 am

Bob, I'd love to have one, but on a limited budget.

Brokencase, perhaps I should have written, "... on the high side, above NORMAL." The gauge had always registered between R & M in the letters "NORMAL" before the sensor disintegrated. Now its above the N, just touching or under the lower of the two hash marks indicating very hot (overheating).

brokencase
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Re: Coolant Temperature Sender

Post by brokencase » Fri Sep 13, 2019 9:01 pm

John - You need to confirm coolant temp by another means. You could be running hot.

john keefe
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Re: Coolant Temperature Sender

Post by john keefe » Sat Sep 14, 2019 12:22 pm

Ha! I thought those lazer thermometers were all in the $250+ Snap-On tool range. I know an HVAC contractor who spent more than that on his to evaluate windows, doors, etc.. Didn't even think about the "home use/cooking" $20 models, so I'll pick one up later today. Thanks for the advice.

john keefe
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Re: Coolant Temperature Sender

Post by john keefe » Sun Sep 15, 2019 9:35 pm

OK, thermometer reading is at 178deg., with coolant gauge needle at the edge of the "normal" box, just before it crosses over into the red. Since this is a dedicated circuit from the sender, and the gauge was working fine before, I conclude the Euro sensor is not calibrated to gauge.

So... again, would a resistor in-line before the gauge work to step down the signal voltage? Assuming its a 5V signal, what do you think the resistor should be to drop it 30% or so?

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