Author Topic: Temp sending unit for a 69  (Read 439 times)


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Temp sending unit for a 69
« on: April 26, 2019, 10:30:15 AM »
I have tried two different units with the same incorrect reading. Not sure if my gauge is out of calibration or what? I have grounded the gauge and it goes all the way to H. My gauge needle rests way below C when cold and rises slightly past the first mark, thermostat opens and it then settles back down to the first mark on the gauge. I have had two other 69's with gauges and as I recall the needle would rest at the first mark when cold not positive. I am using NAPA part number TS 6469 at the moment. If someone has another part number maybe with a different resistance let me know.


'69 RS Z/28 65B, 711 Flat hood no spoiler, endura, 4:10 43K miles
69 X77 Z/28 69 69 711 Original Paint Unrestored (Sold)
'69 X66 Convertible 69B 712 auto, (Sold) 44K miles


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Re: Temp sending unit for a 69
« Reply #1 on: April 26, 2019, 09:16:14 PM »
My suggestion is to take a reading with a laser heat gauge at the housing to determine the actual temperature there, cold, operating but not yet open and after opening. Far simpler than hooking up a new sending unit. Once you know the differential the ratio can be applied to the resistance values of the sending unit...

There must be far more knowledgeable participants on this Board who can give you a correct part number. When I did a '61 Vette it took at least 5 or 6 different sending units (repro, junkyard and "original") before the gauge was 'accurate'.



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Re: Temp sending unit for a 69
« Reply #2 on: May 10, 2019, 03:20:35 PM »
 I replaced one years ago with a standard ignition brand & it seemed ok , never actually checked the temp .. But if your needle is really low can you adjust the needle? Iíve always wondered how the gauges were marked v/s actual degrees..Mine was lying to me & said it was boiling & it wasnít..


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Re: Temp sending unit for a 69
« Reply #3 on: May 11, 2019, 10:19:14 AM »
This thread may help check the correct sender, cross-referenced back to the GM part:
Tim in Australia.
1969 04A Van Nuys Z/28. Cortez Silver, Dark Blue interior, VE3 bumper, Z21, Z23, D55/U17, D80, flat hood.
Sold at Clippinger Chevrolet in Covina, CA. Ex-Racer at Lions Dragstrip in Long Beach.


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Re: Temp sending unit for a 69
« Reply #4 on: May 12, 2019, 01:39:58 AM »
One of these may be of help to you, the Niehoffs are more available and affordable compared to the original GM units. They can usually be found online at reasonable prices, looks are similar the originals, too.

1968 Z28 M21/U17 BRG/W
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06