Fuel Tank Sender

[NIPete]

Hi. Hopefully somebody can help!. The fuel gauge on my 1967 Minor Saloon seems to be faulty. It works when tank is half full or less. However when filling tank the gauge shows empty. Not until the petrol runs low and you go over a ramp / bump the gauge registers again.

Could this be a sticking float or is the unit likely to need replacing. Im willing to have a go at removal and repair but wondered if these items are normally servicable.

Any thoughts or comments would be greatly appreciated.

[dalebrignall]

it sounds like its sticking i have a new one in mine and it stuck at 3/4 full on the way down from yorkshire.when i got home 200 miles away i went over a bump andwas under 1/4.new ones are available from bull motiff.there are two types so make sure you get the correct one

[NIPete]

Thanks Dale for your reply.I have since removed,cleaned and replaced th sender unit.Gauge is showing half full now when car seems to have more fuel than that.Looks like I need a new one.

[rob.hardy1]

i fitted a new sender to my 67 traveller ( that sounds so COOL to say, its the only job i've ever done on my own ) The part was about £12 so i thought not worth messing with. Disconnect the spade clip from the top of the tank and earth it, it should go to full. The one i took out was pretty well seized and rivetted together so not much chance of reliable servicing

[Willie]

If you have fitted the sender in the wrong position into the tank it can be prevented from rising high enough to read 'full' when it should do.
Looking from the rear of the car the sender units terminal should be on the left hand side.

[NIPete]

If you have fitted the sender in the wrong position into the tank it can be prevented from rising high enough to read 'full' when it should do.
Looking from the rear of the car the sender units terminal should be on the left hand side.

thanks Rob and Williefor comments. Have just checked position of sender in tank as per Willie's suggestion and currently sender is fitted as straight up and down,ie float is pointing straight out of the rear of the boot., due south as it were if the bonnet is due north.Ref Willie's note the terminal is at about 12.15 on the clock face.

[Willie]

That is wrong, the float swings across the car not front to rear but if it is
180 degrees out the float hits an internal obstuction.

[jackkelleher]

Aha! That explains a lot. I've had the same problems, never got round to asking....

[Axolotl]

Looking from the rear of the car the sender units terminal should be on the left hand side.

This must vary from car to car, or time to time. My Traveller has the (Lucar) terminal on the right. It has had two senders, because the original one leaked, and neither had a problem with the float hitting any obstruction.

Did this change with the old (screw terminal) vs. new (Lucar) style sender?

[Willie]

Axelotti, you are absolutely right! I have just dismantled the boot gear
in the snow and the Lucar blade is pointing to the right,looking from the
rear. I remember the original nutted terminal pointing the other way but
I swopped them many years ago. I have never understood why the
sender unit was not made so that it would only fit one way round because if
it is in the wrong position the reading will not cover the full range. The
criteria would appear to be that the Lucar blade should be in line with
the rear axle i.e. across the car wheel to wheel. That is assuming that the Lucar blade was always bent in the same direction during manufacture which is likely. We have seen many queries on here re faulty readings which were resolved by repositioning the sender.
If this exercise does not improve the readings it is always worth supplying a good earth to the tank so check that rust is not causing the problem.