I don't know what voltage you should expect, but I do know that if you take out the sender you will most likely see wires wound around a flat piece of bakelite, and an arm which travels across them. Those windings tend to bunch up due to the arm pushing them.
Apart from getting a new one, I've never been sure how to fix this. The arm only just touches the windings, so you don't want to stuff around with it all too much. But I did once entertain the thought of pushing them all back where they should be and trhen super gluing them in place.
Or getting the same kind of card from another car and hoping the resistance is the same.
HiPics below of a new old stock sender that I have if they are of any use. '12V' is noted on the white plastic section.
Upon inspection they don't look to be very solid or 'rebuildable' at all. As described by Beano above the arm only just touches the winding or metal strip and the whole thing is very delicate.
I had a fluctuating gauge in the past and an auto electrician just popped the dash top off and added an earth direct from the back of the gauge to part of the chassis metal nearby and it fixed the issue. Id try that first. Sounds like you have voltage at the rear of the car so it may be at the gauge area.
This gauge is for an 'Early' car as per the sticker and Im not sure if they changed later on or when.
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Adding an earth was exactly what i did to a 604 and it was actually accurate, possible the only accurate 604 fuel gauge ever !!!Pics below of a new old stock sender that I have if they are of any use. '12V' is noted on the white plastic section.
Upon inspection they don't look to be very solid or 'rebuildable' at all. As described by Beano above the arm only just touches the winding or metal strip and the whole thing is very delicate.
I had a fluctuating gauge in the past and an auto electrician just popped the dash top off and added an earth direct from the back of the gauge to part of the chassis metal nearby and it fixed the issue. Id try that first. Sounds like you have voltage at the rear of the car so it may be at the gauge area.
This gauge is for an 'Early' car as per the sticker and Im not sure if they changed later on or when.
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thats right, gauge cant be wrong thenI thought 604's all ran around near empty?