Series 2 fuel gauge is always showing full

Hi,
I have a issue with my series 2 fuel gauge always reading full.
I have 10v onto the gauge and 6.5v coming back out of the gauge which goes off to the sender unit. If i remove the spade connector from the sender the gauge still reads full. If i earth that wire to the body the gauge drops to empty. It's a negative earth system and im assuming the sender earths itself through the bolts that hold it to the tank as there's no earth connection. Can anyone tell me if the gauge is faulty or the sender unit? Cheers

Car new to you or a new fault?

Have you tried putting a decent earth onto the sender plate, if you look on Paddock spares and search "Series 2 fuel sender unit " on the 3 units shown they all have an earth tag fitted to the sender plate. Is yours petrol or diesel.
It would help to identify which sender you have as there are 2 terminal units with no earth tag.

Series 2 sender is different type to series 3 and needs 12V post a picture of your gauge and sender the gauges should have an arrow point if series 2 and sender has raised box on it . Series 3 gauge just has pointer snipped at thge end no arrow head sender is flat on top. The two set ups are not compatible.

Blackburn said:

Series 2 sender is different type to series 3 and needs 12V post a picture of your gauge and sender the gauges should have an arrow point if series 2 and sender has raised box on it . Series 3 gauge just has pointer snipped at thge end no arrow head sender is flat on top. The two set ups are not compatible.

Click to expand...

I think the op has gone!

I'm back.

So i have found the issue which turned out to be the fuel sender. Its the type with the box on top, and i can confirm its a series 2 gauge with the arrow.
The slider that runs up the coil has a load of play so its's not coming in to contact with the coil.

New problem - So i have bought a new sender from paddocks which is supposed to work with the 2/2A. Works perfectly but it's all in reverse... So the sender is in the empty position but the gauge reads full and vise versa. Checked the ohms reading on the original smiths and turns out they work in the opposite way in terms of resistance.

I'm told the vehicle is ex MOD. Would the fuel sender be different to a normal civillian one?

MrCountry said:

I'm back.

So i have found the issue which turned out to be the fuel sender. Its the type with the box on top, and i can confirm its a series 2 gauge with the arrow.
The slider that runs up the coil has a load of play so its's not coming in to contact with the coil.

New problem - So i have bought a new sender from paddocks which is supposed to work with the 2/2A. Works perfectly but it's all in reverse... So the sender is in the empty position but the gauge reads full and vise versa. Checked the ohms reading on the original smiths and turns out they work in the opposite way in terms of resistance.

I'm told the vehicle is ex MOD. Would the fuel sender be different to a normal civillian one?

Click to expand...

Early series 2 senders are quite rare, I believe thats what you have and I do not think you can buy them any more, original or copy.
They work arse about face compared to the later ones hence the reason your gauge is now reading incorrectly.