Fuel Sending Unit Question
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Fuel Sending Unit Question
Hello,
I installed the complete new fuel pump and sending unit assembly in my 1982 Corvette. I soldered the two connection needed and heat shrinked them and before putting in the tank I checked to make sure the float triggered the fuel gauge in the car. Once I added the fuel nothing happens. I pulled it back out and tested again and it worked outside the tank. what could be causing this to not work while in the fuel? The fuel pump works and the cars runs fine.
I installed the complete new fuel pump and sending unit assembly in my 1982 Corvette. I soldered the two connection needed and heat shrinked them and before putting in the tank I checked to make sure the float triggered the fuel gauge in the car. Once I added the fuel nothing happens. I pulled it back out and tested again and it worked outside the tank. what could be causing this to not work while in the fuel? The fuel pump works and the cars runs fine.
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Is the system grounded back at the tank? The only 'signal' coming from that sender is the resistance of the slide rheostat attached to the float arm. If you measure the resistance between the sender signal wire and chassis ground, you should get something in the 0 ohm (empty) to 90 ohm (full) range. If you don't get a reading, either there is a problem with the signal wire or the ground connection (to chassis) is missing at the tank.
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I will have to try and peak in there while lowering it down in. I am not doing any grounding other than the wires already connected on the complete assembly. When I take it out of the tank I hold it up and lift the float and watch the gas gauge rise. I don't see any additional wires beside the connector outside the tank.
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
What does the gauge read when installed, high/low? It may be hanging up inside the tank, it is somewhat a dick dance to get them in correctly. If it works electrically outside the tank you have issues inside. There is also a bladder inside the tank on an original 82 tank that may be causing you issues as well almost 40 years later. I would have a good look inside the tank first. The new aftermarket tanks do not come with the bladder in them. There is no other ground for that unit other than the connector that attaches to it.
Last edited by Buccaneer; Jan 19, 2021 at 08:28 AM.
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The gauge reads empty. I added 10 gallons of gas. I will take it loose and move it around to see if it could be hanging up inside. If it is I am assuming I would need to gentle adjust the float arm by bending it some?
Before I installed the new assembly I completely cleaned the tank. I didn't have any rubber bladder but the tank was plastic inside.
Before I installed the new assembly I completely cleaned the tank. I didn't have any rubber bladder but the tank was plastic inside.
Safety Car
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Never saw or heard of plastic inside an 82. I have had my original tank out of my car, so I know there is a bladder and found another original tank to install, same thing. This was before they even were re-poping 82 tanks and you couldn't buy one.
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you are correct it is a rubber bladder and not a plastic liner.
I can see the float was rubbing on the bladder but not sure why even tweaking the float arm it doesn't seem to want to work correctly when I align the bolts. It goes to completely empty and I have gallons of gas in it so it should register something. It seems to be functioning correct when I raise it manually slowly.
I can see the float was rubbing on the bladder but not sure why even tweaking the float arm it doesn't seem to want to work correctly when I align the bolts. It goes to completely empty and I have gallons of gas in it so it should register something. It seems to be functioning correct when I raise it manually slowly.
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Hello,
i recently had my oil change on my 17 grand sport when it was refilled it only took 6.5 qts but the dip stick shows its full. There are no service or trouble lights displaying. We drained the oil and repeated the process. Has anyone else experienced the same problem? The book calls for 9.8 ots. With the dry slump system.
i recently had my oil change on my 17 grand sport when it was refilled it only took 6.5 qts but the dip stick shows its full. There are no service or trouble lights displaying. We drained the oil and repeated the process. Has anyone else experienced the same problem? The book calls for 9.8 ots. With the dry slump system.
Safety Car
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Hello,
i recently had my oil change on my 17 grand sport when it was refilled it only took 6.5 qts but the dip stick shows its full. There are no service or trouble lights displaying. We drained the oil and repeated the process. Has anyone else experienced the same problem? The book calls for 9.8 ots. With the dry slump system.
i recently had my oil change on my 17 grand sport when it was refilled it only took 6.5 qts but the dip stick shows its full. There are no service or trouble lights displaying. We drained the oil and repeated the process. Has anyone else experienced the same problem? The book calls for 9.8 ots. With the dry slump system.
Last edited by Buccaneer; Jan 23, 2021 at 03:26 PM.
