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TR6 Fuel Gauge
- Thread starter davjac889
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Is your temp gauge working? You need to have +10 volts going to the gauge, so get your digital volt meter and verify that.
Then unplug the ground wire off of the sender and ground it to the car... see if the gauge goes to full. If it does, it's either the fuel sending unit in the tank or the plastic float is full of fuel. If the gauge does not move after you ground it, then I would suspect the gauge is faulty.
Then unplug the ground wire off of the sender and ground it to the car... see if the gauge goes to full. If it does, it's either the fuel sending unit in the tank or the plastic float is full of fuel. If the gauge does not move after you ground it, then I would suspect the gauge is faulty.
TR3driver
Great Pumpkin - R.I.P
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BTW, when you check power (either at the gauge or at the sender), you may see the voltage jump between 0 and full battery voltage. That is normal if you have the factory type "voltage stabilizer".
I don't recall the TR6 layout very well, but on a Stag the tank sender is a lot easier to access than the gauge. If that is the case, you might want to start there instead. If you pull the green/black wire off the sender, you should be able to see the power being passed through the gauge (ignition on of course), either 10v or flashing 12v/0v (it averages to 10v). And if you can ground that wire and see the gauge move, the sender is the problem.
Lucas warns against running them on full battery voltage, so if it does turn out that the gauge is burned out, be sure to check that the VS is working. If the coil inside burns out, or the VS isn't grounded, it may let the gauge burn out when you have a full tank of gas (needle beyond the full mark).
But my first guess would be a bad sender, either open resistor or the float doesn't.
I don't recall the TR6 layout very well, but on a Stag the tank sender is a lot easier to access than the gauge. If that is the case, you might want to start there instead. If you pull the green/black wire off the sender, you should be able to see the power being passed through the gauge (ignition on of course), either 10v or flashing 12v/0v (it averages to 10v). And if you can ground that wire and see the gauge move, the sender is the problem.
Lucas warns against running them on full battery voltage, so if it does turn out that the gauge is burned out, be sure to check that the VS is working. If the coil inside burns out, or the VS isn't grounded, it may let the gauge burn out when you have a full tank of gas (needle beyond the full mark).
But my first guess would be a bad sender, either open resistor or the float doesn't.
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My experience: Be wary of a cracked float bubble, and what MRV says is correct; there's a great replacement float made of brass or copper and used in a Ford; it fits perfectly.
Unless you had an electrical problem recently, there's a good shot that's the problem. One heck of pain to verify, but if you have current to the gauge, it's possible that's the problem.
Unless you had an electrical problem recently, there's a good shot that's the problem. One heck of pain to verify, but if you have current to the gauge, it's possible that's the problem.
dklawson
Yoda
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Pictures and part numbers for the Ford float can be seen in a picture in the link below. (Sorry, this is a Google storage location and it typically won't allow me to post direct links).
https://www.sites.google.com/site/purlawson/home/pictures
Look on the left for the gauges folder and the first link "Floats-Smiths-n-Ford.jpg" The Ford float is available from many sources (eBay, Amazon, speedshops, etc.) as a LOT of non-Ford cars use it as a replacement.
Start your troubleshooting by looking at the temperature gauge as Gilderman suggested (assuming it is still an electric temperature gauge). If your car still has the Smiths electric temperature gauge and it is working normally, that should indicate that the voltage stabilizer referenced by others above is putting out the average 10V Randall mentioned. Of course, you should also check that all the wires are connected both at the fuel gauge and at the sending unit.
Once you have access to the sending unit, remove the green/black wire connected to it and with the ignition switch in the run position, hold the terminal on the green/black wire to a bare metal ground on the car. If the fuel gauge goes to full, the gauge and the green/black wire are OK. If it does not, you could have a problem with the gauge or the wiring. I don't remember if the TR6 has 2 wires on the sender or not. If there are two wires on the sender, the second wire will be "black". With the ignition still in the run position, hold the terminal of the green/black wire against the terminal on the sender's black wire. Again the gauge should go to "full". If it does not go to full this time but did go to full when you grounded the green/black wire, this indicates a problem with the black wire having lost its connection to ground.
EDIT: If you determine the float is the problem and you buy the Ford float, take one additional step before fitting it to your car. The float arm for the Smiths sending unit will have a loop of wire on the end. Deburr the cut end of that wire loop with a fine file before fitting the Ford part. I failed to do this the first time I used one and in a few weeks my float failed. I small burr had cut through the thin brass allowing the float to fill with gas and sink. That's easily fixed with a bit of solder but it meant taking everything apart again and emptying/drying the float.
https://www.sites.google.com/site/purlawson/home/pictures
Look on the left for the gauges folder and the first link "Floats-Smiths-n-Ford.jpg" The Ford float is available from many sources (eBay, Amazon, speedshops, etc.) as a LOT of non-Ford cars use it as a replacement.
Start your troubleshooting by looking at the temperature gauge as Gilderman suggested (assuming it is still an electric temperature gauge). If your car still has the Smiths electric temperature gauge and it is working normally, that should indicate that the voltage stabilizer referenced by others above is putting out the average 10V Randall mentioned. Of course, you should also check that all the wires are connected both at the fuel gauge and at the sending unit.
Once you have access to the sending unit, remove the green/black wire connected to it and with the ignition switch in the run position, hold the terminal on the green/black wire to a bare metal ground on the car. If the fuel gauge goes to full, the gauge and the green/black wire are OK. If it does not, you could have a problem with the gauge or the wiring. I don't remember if the TR6 has 2 wires on the sender or not. If there are two wires on the sender, the second wire will be "black". With the ignition still in the run position, hold the terminal of the green/black wire against the terminal on the sender's black wire. Again the gauge should go to "full". If it does not go to full this time but did go to full when you grounded the green/black wire, this indicates a problem with the black wire having lost its connection to ground.
EDIT: If you determine the float is the problem and you buy the Ford float, take one additional step before fitting it to your car. The float arm for the Smiths sending unit will have a loop of wire on the end. Deburr the cut end of that wire loop with a fine file before fitting the Ford part. I failed to do this the first time I used one and in a few weeks my float failed. I small burr had cut through the thin brass allowing the float to fill with gas and sink. That's easily fixed with a bit of solder but it meant taking everything apart again and emptying/drying the float.