hi all, i was looking at setting up the fuel system today when i came across a problem, when calibrating the fuel sender unit does the sender arm have to be vertical when there is no fuel in the tank, or does it just have to be resting on the bottom. i assume that as the tank is filled with fuel then the float on teh end of the arm will more through its arc path until it is horizontal when the tank is full?

thanks guys, pictures would help if you can

Alex

i got the empty point (lowermost) by holding the sender to the outside of the tank and bending the wire to the poing where the float is at the bottom when gauge reads zero. This has left me with a small amount of fuel still in bottom of tank. Then lift the sender till it reads max and modify the bend to suit - again re-checking the zero point. You can also get it close on the bench with a piece of paper - marking the top and bottom of tank and bending so the float can work in a complete arc. Its worth checking with sender wired to gauge first to work out what angles read empty and full first.

I havent quite got the full to read right but this is the general method.

The other method involves cutting the wire and joing with something like a screw in cable connector. Bending is preferred if you can get it right. It is fiddly.

Make it so that the float just barely is off the bottom of the tank when empty. This way it will read empty correctly. It may stay at full for a while when you fill up but seems better to know when youre nearly out of fuel rather than be accurate at 3/4tank
Cheers.

Im running bird clocks with an mk sender and still cant set the bloody thing up, ive ran out 3 times now!!

What sender are you using? got mine from Greengauges and when fitted following instructions to the letter found the gauge to be reading backwards . Don't think I'm the only person who has had this problem so may be worth checking sender operation with a multimeter before fitting if you have one of theirs.

Don't know if te greengauges sender is like the VDO one but just fit the arm in from the other side.
Rescued attachment sender.jpg