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My 1970 vette gas gauge registers past the full mark. I bought a new sending unit and it did not solve the problem, Anyone have this problem and tell me how to fix it. Thanks
Does it move toward Empty as you use the fuel... as in, is it only registering full after filling up or is it always full and never moves? The older sender/gauge technology certainly wasn't all that sensitive or accurate. I recall my cars staying on Full for extended periods of time, only to begin dropping after a number of miles (like 75+).
My 1970 vette gas gauge registers past the full mark. I bought a new sending unit and it did not solve the problem, Anyone have this problem and tell me how to fix it. Thanks
you need to measure the sending unit resistance in the full up position. Normally 90 ohms is considered full.
Then measure the resistance required to position the gauge at the full mark. They should match in an ideal case.
After replacing a fuel gauge they usually are off. Wilcox corvette. did sell a adjuster electronic circuit to help calibrate the sending unit / guage readings.
If it is way way past full, then you have a connection problem. Like mentioned above, 90 ohms is full, infinite ohms (no connection) is like way to the right. I just spent a few days getting mine adjusted so E was E (different problem). The new sender I got showed E when it was really about 1/4. I had to reach into the tank and bend the sender down to get it right.
Does anyone have any experience with the 90 ohm c2 fuel sending unit from csmdowest? I have tested several 120 ohm versions and they are not accurate. They read correct (120 ohms) at full tank but at 3/4 tank they read approx 25 ohms. I have modified the float position and get a slightly better reading but still significantly off. I don’t believe they can be made accurate do to the position of the rheostat (sp) and the resulting arc of the arm. At mid arc position I get 60 ohms but that position is above the 3/4 mark and above 7.5” of gas in the tank. tks, jb
Note the float has been removed to enable reading the diagram I created showing gas tank level, max and min arc of float, and ohm outputs at various positions.
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Does anyone have any experience with the 90 ohm c2 fuel sending unit from csmdowest? I have tested several 120 ohm versions and they are not accurate. They read correct (120 ohms) at full tank but at 3/4 tank they read approx 25 ohms. I have modified the float position and get a slightly better reading but still significantly off. I don’t believe they can be made accurate do to the position of the rheostat (sp) and the resulting arc of the arm. At mid arc position I get 60 ohms but that position is above the 3/4 mark and above 7.5” of gas in the tank. tks, jb
Note the float has been removed to enable reading the diagram I created showing gas tank level, max and min arc of float, and ohm outputs at various positions.
Please don’t tack onto created from 2022 with a completely unrelated question.
