sending unit questiion
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Joined: Dec 2001
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From: Danville IL
sending unit questiion
I put a vortec engine in my 76 vette the tempature sending unit out of my stock engine will not fit the vortec heads because it is 1/2 & and the vortec head takes a 3/8 any suggestion on what i can do to solve this problem i no when using a differnt sending unit you have to be careful of the olms because this can change the reading of your gauge ?
Thanks Kenny
Thanks Kenny
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Joined: Aug 2000
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From: Semper ubi, sub ubi
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Re: sending unit questiion (sprtsjunky32)
I've got the same problem on my Vortec heads, I was told to try the sending unit from an 82 'vette. I haven't tried it yet, because I haven't started my motor yet. There is a place on the Vortec Performer manifold for a 1/2" temp sender out of my 69 engine, I'm going to put it there and hook it up. It won't be as accurate as it was in the head, but it is better than nothing. After I get some readings I'll try switching to the 82 sender and compare the readings.
There have been a number of post here about the inaccuracies of the new senders, some people have gone as far as to get an aftermarket gauge and hook it up under their hood for reference. With a matched gauge and sender you should be close enough to be safe.
A good shop can also use an infrared heat gun to help you calibrate your gauge by installing resistors in the gauge wire.
There have been a number of post here about the inaccuracies of the new senders, some people have gone as far as to get an aftermarket gauge and hook it up under their hood for reference. With a matched gauge and sender you should be close enough to be safe.
A good shop can also use an infrared heat gun to help you calibrate your gauge by installing resistors in the gauge wire.
Melting Slicks
Joined: Jul 1999
Posts: 3,030
Likes: 17
From: White Pine / Dandridge TN
Re: sending unit questiion (Smokehouse69)
No need to use an aftermarket gauge or sender from the incorrect year. You can find an adapter at your local hardware store. I'm also using a new a/c delco temp sending unit with no problem. This should be an easy project.
Regards,
Jim
Regards,
Jim
Drifting
Joined: Aug 2000
Posts: 1,758
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From: Medford, Or
Re: sending unit questiion (sprtsjunky32)
sprtsjunky32-
I had the same problem with my LT1 conversion. The stock transducer for the '76 gauge measures around 800 ohms cold, where as the '95 transducer measured 2400 ohms. I installed a 150 ohm resistor in parallel to the sending unit wire and read the exact temperature as the PCM reads from the transducer. 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. I verified that the temperature reading at the PCM was the same as the temp. gauge by using the X-Ray OBD-1 PCM reader. You can use an ’95 Corvette or Camaro Z28 sending unit. I used the dual sending unit from ’94 thru ’95 ZR1. It feed both the PCM and the gauge and is located in the LT1 water pump. The part numbers for the 3 wire dual sending unit and connector pigtail are available at any Chevrolet dealer are:
PN-10096181 - PCM/Gauge sending unit. Used on the'94 thru '95 LT5 ZR1 Corvette
PN-12102748 - Connector Pigtail
Good luck,
Dan
I had the same problem with my LT1 conversion. The stock transducer for the '76 gauge measures around 800 ohms cold, where as the '95 transducer measured 2400 ohms. I installed a 150 ohm resistor in parallel to the sending unit wire and read the exact temperature as the PCM reads from the transducer. 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. I verified that the temperature reading at the PCM was the same as the temp. gauge by using the X-Ray OBD-1 PCM reader. You can use an ’95 Corvette or Camaro Z28 sending unit. I used the dual sending unit from ’94 thru ’95 ZR1. It feed both the PCM and the gauge and is located in the LT1 water pump. The part numbers for the 3 wire dual sending unit and connector pigtail are available at any Chevrolet dealer are:
PN-10096181 - PCM/Gauge sending unit. Used on the'94 thru '95 LT5 ZR1 Corvette
PN-12102748 - Connector Pigtail
Good luck,
Dan
