Fuel Tank sender unit
Discussion
has anyone got their car in bits and can easily check the resistance values of the fuel tank sender unit of a Taimar or 3000M?
Looking to make some aluminium fuel tanks and would like to supply with a modern bolted sender unit, but need to know the resistance in Ohms when empty and full if possible please, so that the sender until will work the guage properly.
Looking to make some aluminium fuel tanks and would like to supply with a modern bolted sender unit, but need to know the resistance in Ohms when empty and full if possible please, so that the sender until will work the guage properly.
If you have Smiths gauges (I think that's right for an M ) then the fuel sender should range from about 260 ohms empty to 20 ohms full, with a bit of variation around those numbers, and about 80 ohms half full.
As far as I know, most Smiths senders are the same calibration, so try any BL/Triumph one which fits can be adjusted for correct sweep, but I could be wrong on that.
I used a Dolomite one in my S3 I think..... or it could have a been a Triumph 2500 estate .... can't remember for sure.
I repaired my Stewart Warner one in the wedge, the wiper had broken, luckily the resistance wire winding was fine...
As far as I know, most Smiths senders are the same calibration, so try any BL/Triumph one which fits can be adjusted for correct sweep, but I could be wrong on that.
I used a Dolomite one in my S3 I think..... or it could have a been a Triumph 2500 estate .... can't remember for sure.
I repaired my Stewart Warner one in the wedge, the wiper had broken, luckily the resistance wire winding was fine...
For info, if you're fiddling around with gauges etc.....
Smiths used 10 volt setup (with the mechanical voltage regulator) and I think temp and fuel gauges were actually calibrated the same....
they are both hot wire types, and about 15-20 ohms gives full scale, ~ 60 is half scale, and 250 or more is empty/cold, or hardly any movement.
Ford used 5 volt setup, with lower resistances, so their half scale is more like 30-40 ohms .... so those lower resistance fuel senders are probably Ford ones....
That doesn't cater for all the aftermarket ones though ....who knows what they use...
Today of course, you can easily make up an LM317 adjustable electronic regulator, and they are cheap enough to have one per gauge if you wish, which gives a whole new way of adjusting the calibration......
Smiths used 10 volt setup (with the mechanical voltage regulator) and I think temp and fuel gauges were actually calibrated the same....
they are both hot wire types, and about 15-20 ohms gives full scale, ~ 60 is half scale, and 250 or more is empty/cold, or hardly any movement.
Ford used 5 volt setup, with lower resistances, so their half scale is more like 30-40 ohms .... so those lower resistance fuel senders are probably Ford ones....
That doesn't cater for all the aftermarket ones though ....who knows what they use...
Today of course, you can easily make up an LM317 adjustable electronic regulator, and they are cheap enough to have one per gauge if you wish, which gives a whole new way of adjusting the calibration......
Has anyone fitted a bolt in sender to the existing tank? The bayonet fitting never seems to seal properly, at least for long.
Thinking of replacing the existing one with a 5 hole bolt in sender. I'll have to grind off the existing fitting and obviously drill some holes. Anyone done same? Alternative would be to have a proper fitting inserted into tank.
I know it won't be the same without the smell of petrol
Thinking of replacing the existing one with a 5 hole bolt in sender. I'll have to grind off the existing fitting and obviously drill some holes. Anyone done same? Alternative would be to have a proper fitting inserted into tank.
I know it won't be the same without the smell of petrol
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