Fuel Gauge Stopped Working - Page 2

GC427 · #21 (**permalink**) 02-01-2011, 09:05 PM

Blas,

The resistance test across the two terminals on the back of the fuel gauge indicates an OPEN circuit. NO READING whatsoever. It appears the fuel gauge part number is BF2242-03C with Caerbont Automotive LTD above the part number. The voltage reading across the two terminals with the key in the off position is 0.00 volts. With the key in the on position, the voltage reading across the two terminals is 9.86 volts. Looks like the fuel gauge is the problem. I did not check the voltage from each wire connected to the fuel gauge to ground. Do you think it's the fuel gauge?

I tried to respond sooner but could not log-in and kept getting a Database error message: "The Club Cobra database has encountered a problem." Seems to be working now.

Gil

Blas · #22 (**permalink**) 02-01-2011, 09:43 PM

A resistance test across the two terminals on the back of the gauge (with the wiring disconnected) a good gauge reads about 62 Ohms.
The wires were off for your resistance test right?
0 Volts is correct for the key off position test. 9.8V is good for power from the stabilizer. (to power feed side of the gauge)
So voltage going to the gauge means the stabilizer is ok...
I'm a little confused with the 9.8V THRU the gauge comment. That says there is conductivity thru the gauge...
But 0 Ohms resistance THRU the gauge means it's a paper weight...But you get voltage thru the gauge?
Connecting the 2 wires at the tank with the ignition on does not move the gauge?
Check your email.

GC427 · #23 (**permalink**) 02-02-2011, 10:06 AM

Blas,

Yes, the wires where off the fuel gauge for the resistance test.

Clarification: The 9.8 volt reading is across the wires to the back of the fuel gauge with the fuel gauge disconnected.

The reading is not zero ohms through the fuel gauge. Explanation about this ohm meter: When I touch the ohm meter probes together, the meter reads 0.00 ohms. The meter reads 0.L when the probes are not touching anything. When I place the meter probes across the posts on the back of the fuel gauge, the ohm meter reading is 0.L, as if the circuit inside the fuel gauge is a completely OPEN circuit. Therefore, there is no conductivity through the fuel gauge. At least that's what I believe the reading indicates. You indicated 0 ohms resistance through the fuel gauge means the fuel gauge is a paper weight. I'm guessing if there is no conductivity whatsoever through the fuel gauge, it's time for a new fuel gauge. I'll check my e-mail.

Gil

Blas · #24 (**permalink**) 02-02-2011, 11:13 AM

Great...
Now back to shoveling snow....18"+ with 36"+ drifts.....
Wonder if they have a plow attachment for my SPF?

GC427 · #25 (**permalink**) 02-02-2011, 11:16 AM

Blas,

I talked to Chuck at APT Instruments International (GaugeGuys.com). He said, as you indicated, the ohm reading across the posts (with no wires connected) should read about 62 ohms. Chuck also mentioned that if there is no ohm reading whatsoever (in this case) the fuel gauge is defective. I'll have the new gauge by Friday.

Thanks to all for your help.

Gil

ReMorton · #26 (**permalink**) 05-15-2011, 04:51 PM

...I'm having just the opposite problem. Smiths fuel gage is pegged on full, and only when about 1/2 empty does it move. Float had pinhole leak and was replaced by previous owner. Apparently the gage needs to be recalibrated.
Any suggestions on how to recalibrate?
Bob
SPO2089

Barnsnake · #27 (**permalink**) 05-15-2011, 09:26 PM

Bob:
The previous owner may have installed the sender turned the wrong direction or, more likely, bent the float arm during installation. He may also have installed a replacement sender with the wrong resistance range.
Most senders are variable resistors moved by a float on the end of a wire arm. It should be verified that the arm can move freely in the tank without striking obstructions, like baffles or return tubes. To calibrate the sender you bend the arm so the float is at the bottom of the tank at the bottom of its travel, and at the top of the tank at the top of the sender travel. Many senders have a telescopic section to accommodate various tank depths, while others pivot at the top and have a longer float arm that must be cut and/or bent to match the tank depth.
Remove the sender and attach a ohm meter to the sender post and the mounting plate. Move the float arm through its range and note the resistance. It should smoothly change resistance throughout the travel. Verify that the resistance range matches the specified range for your gauge. Measure the depth of the tank at the sender location and bend (or otherwise adjust) the float arm to that the top of the float is full up when 1/8"-1/4" below the plane of the mounting plate and fully down when the bottom of the float is at tank depth below the mounting plate. Make sure it is pointing in a direction free of obstructions when reinstalled.

ReMorton · #28 (**permalink**) 05-16-2011, 10:07 AM

Thanks for the help. Yeah, I suspected that the problem probably has to do with the floats, but was reluctant to open the gas tank up and start fooling with the hardware until I had a better basis to start checking, and could do it safely. So, we'll proceed and see if the situation improves.
One of the other members has the same problem with his level gage, so I'll pass the info along to him also.
Bob.