74 fuel guage issue
Thread Starter
Intermediate
Joined: May 2018
Posts: 30
Likes: 0
From: Nova Scotia, Canada
74 fuel guage issue
The fuel sending unit has 23 ohms and moves when I manually lift the float. Wires, ground and tan connect to the fuel guage. 12 volts at the guage cluster. When I manually move the guage needle on the cluster and turn on the key, it will go from empty to full over hard on the needle stop. So all the parts work. Why doesn’t the guage read correctly?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Your sending unit should go from basically '0' to 90 ohms. I have seen them to to like 110 ohms...but you get the point.
I do not know how you are testing this or your set-up. But I can check the sending unit out of the car to see if the sending unit is fine.
Depending on the year model. I can check them while they are still installed in the fuel tank.
DUB
I do not know how you are testing this or your set-up. But I can check the sending unit out of the car to see if the sending unit is fine.
Depending on the year model. I can check them while they are still installed in the fuel tank.
DUB
Thread Starter
Intermediate
Joined: May 2018
Posts: 30
Likes: 0
From: Nova Scotia, Canada
Your sending unit should go from basically '0' to 90 ohms. I have seen them to to like 110 ohms...but you get the point.
I do not know how you are testing this or your set-up. But I can check the sending unit out of the car to see if the sending unit is fine.
Depending on the year model. I can check them while they are still installed in the fuel tank.
DUB
I do not know how you are testing this or your set-up. But I can check the sending unit out of the car to see if the sending unit is fine.
Depending on the year model. I can check them while they are still installed in the fuel tank.
DUB
Instructor
Joined: May 2013
Posts: 177
Likes: 17
From: Turin Italy
You could connect an appropriate potentiometer (90 ohms) instead of the sending unit. Maybe you will find a 100 ohms potentiometer because is a more commercial value. But it's ok for the test.
Last edited by oVoSanto; May 20, 2018 at 02:51 AM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
IF the sending unit checks out as I described. IT can be used.
Because going out and getting another tool that will obviously do the same as the GOOD sending unit...is kinda insane.
The gauge is only going to do what it is being told to do from the sending unit...or the tool that you gout and buy.
NOW..if your sending unit is NOT GOOD...that may be your problem.
DUB
Because going out and getting another tool that will obviously do the same as the GOOD sending unit...is kinda insane.
The gauge is only going to do what it is being told to do from the sending unit...or the tool that you gout and buy.
NOW..if your sending unit is NOT GOOD...that may be your problem.
DUB
