fuel sender unit problems

[phila]

Hi,
Just wondering if someone could help me with a bit of advice on my Falcon. (67 club coupe)
Ive attached a picture of the fuel level sender unit. Since I've had my car the gas guage on the dash has never indicated above empty. I drained the tank and removed the unit yesterday. I checked the circuit and contact etc and, while out of the tank, it worked properly. I was able to get the Gas guage to register full on the dash by actuating the float arm while I had it connected. I re-installed the unit and refilled the tank to about 1/3 to 1/2 full and for some reason it still doesnt register past empty again. The pin does move a bit but stops at the empty line.... The only thing I can think of is that the float itself is getting saturated. Can someone tell me if this is possible or if they have experienced the same symptoms? ..
If its just the float bubble I will try to get a replacement. I'm in Australia and the replacement sender units here are not the same so I cant just buy one of ours ....
any help would be greatly appreciated
regards
phil a

[Jon Richard]

I experienced this on a 1970 ranchero and it was indeed the float. The float on my ranchero was brass or tin. I found a pin hole and soldered it, afterwards it worked properly. I have not had this happen with the plastic float but it seems you have eliminated all other possibilities.

[Jeff W]

The float on my '62 had the same problem. I had to solder so many cracks on my brass float I was concerned the extra weight of the solder would cause it to drop so fast it would dent the bottom of the tank. It worked wonderfully for several years. It was only replaced later due to a lager tank installation. Go for it!

[phila]

Jon/Jeff,
Thanks for your replies. I'm going to take the unit back out and have another look ... I never checked if the float is hollow or solid. If its hollow and has a hole that should be OK to fix ..... interestingly though if you check the picture the arm goes right through the middle of the float with a retaining nut on the end . If its solid then I can only assume that it has become porous with age and soaking up the fuel.. If so I'll need to find a replacement or seal it somehow.
regards
Phil

[phila]

Hi all
Looks like it was the float. I removed the unit a week or so ago and removed the old float. I was stumped for a while about what to do , but then realised that I had an old carby float lying around so I adapted the arm to carry the other float and refitted the sender. I works fine but It does need a bit of an adjustment... anyway fixed!
Thanks to those who helped
regards
phil

[redfalken]

GoodOnYa Phil! A float is a float if it floats... And I doubt anyone will see it anyway.

I've heard a lot of people complain about the gauges not being accurate. Mine moves very slow for the first 3/4 tank and then goes to empty pretty quick even though there's still 2-3 gallons in it. Just something I've gotten used to. It's kind of a hassle to empty the tank, make an adjustment, and reassemble until you get it right.

[phila]

Hi
thanks... you're right it wont be seen ....but at this stage the mine is way out .. when the tank is full it only registers at just past half way..... at least its conservative but I think I'll need to adjust it a bit ... the weather is really bad here at the moment as its middle of winter so I might wait a month or so before I have a go next.


regards
phil