Water temp sensor question
Thread Starter
Melting Slicks
Joined: May 2001
Posts: 2,812
Likes: 4
From: Gig Harbor Wa
Water temp sensor question
Right now, I have no working water temp gauge in the car. The sensor for the LS1 is a small metric thread, while the original 70 corvette one is a much larger thread. Does anyone know if I can use the temp sensor from a different GM car and have accurate water temp? I really don't like the idea of drilling and tapping a new hole in my aluminum heads.
Melting Slicks
Joined: Jan 2000
Posts: 2,386
Likes: 3
From: far, far away
Re: Water temp sensor question (70 LS1)
Seems to me, what you need to know is the electrical operation properties of the two standard sending units. If they are the same, or can be made to be the same by adding a resistor or some such (no flames, please, I'm not a double E! :rolleyes: ) then you just connect the new sender to the old gauge.
Don't the electrical temp senders simply vary their resistance with the temperature? If that's right, then you need to know the resistance at full cold and full hot for both the old and new. There's probably some good reason why this won't work, but I don't know what it is. That is certainly where I would start.
Good luck! :seeya
Don't the electrical temp senders simply vary their resistance with the temperature? If that's right, then you need to know the resistance at full cold and full hot for both the old and new. There's probably some good reason why this won't work, but I don't know what it is. That is certainly where I would start.
Good luck! :seeya
Le Mans Master
Joined: May 2000
Posts: 6,493
Likes: 6
From: Bloomington MN
Cruise-In II Veteran
Re: Water temp sensor question (70 LS1)
I would think you would have to find out the resistances of the two temp sensors to see if they are the same. If they aren't, then your guage will read an incorrect temp. The only other thing I can think of would be an aftermarket temp guage and sender. The good thing about that is that they are made in the correct size to fit in the stock location.
AC
AC
Drifting
Joined: Aug 2000
Posts: 1,758
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From: Medford, Or
Re: Water temp sensor question (70 LS1)
Jeff, The stock sending unit for the '76 gauge measures around 800 ohms cold, where as the '95 sending unit reads 2400 ohms. I installed a 150 ohm resistor in parallel to the sending unit wire and read the exact temperature as the PCM. One down fall to this is the temperature gauge will not start reading the engine temperature until around 130 degrees. The needle will only drop down to around 130 degree. From there on the Gauge is very accurate. Go to my web page for more details.
Dan :cheers:
[Modified by vettedan, 5:06 PM 5/13/2002]
Dan :cheers:
[Modified by vettedan, 5:06 PM 5/13/2002]
