Fuel sender not reading

[Ausflyer]

Recently I reinstalled my fuel tank after fixing a fuel flow problem and installing a Moeller fuel gauge. But I found that the Dynon reads the tank as empty. In the VAF archives I found very clear instructions for testing the sender with an ohmmeter. It showed the sender was faulty ? infinite resistance between the screw and the flange, instead of 30 to 200 ohms

I had noted when I tightened the screw on the centre of the sender, that the sender centre turned with the screw with a modest tightening. I left it at that, after doing a few revolutions of the screw plus fitting.

I can?t remember the setup behind that screw and flange, but I fear some wire has been twisted past breaking point. Or could it be a displaced wiper (something else I read in a VAF message)?

So I need answers to a few questions please.
? If the centre piece rotates, could it break the conductors? Perhaps someone could look at an uninstalled sender for me.
? Can the wiper be dislodged?
? Can I simply unscrew the flange, pull out the sender and check it? I?m so tempted.
? Is the sender likely to be repairable? Or should I just order a new one now?
? I don?t think I used unreasonable force to tighten the connector screw. Has anyone else had this problem and made a warranty claim?
Rod

 

[vernhendershott]

Recently I reinstalled my fuel tank after fixing a fuel flow problem and installing a Moeller fuel gauge. But I found that the Dynon reads the tank as empty. In the VAF archives I found very clear instructions for testing the sender with an ohmmeter. It showed the sender was faulty ? infinite resistance between the screw and the flange, instead of 30 to 200 ohms

I had noted when I tightened the screw on the centre of the sender, that the sender centre turned with the screw with a modest tightening. I left it at that, after doing a few revolutions of the screw plus fitting.

I can?t remember the setup behind that screw and flange, but I fear some wire has been twisted past breaking point. Or could it be a displaced wiper (something else I read in a VAF message)?

So I need answers to a few questions please.
? If the centre piece rotates, could it break the conductors? Perhaps someone could look at an uninstalled sender for me.
? Can the wiper be dislodged?
? Can I simply unscrew the flange, pull out the sender and check it? I?m so tempted.
? Is the sender likely to be repairable? Or should I just order a new one now?
? I don?t think I used unreasonable force to tighten the connector screw. Has anyone else had this problem and made a warranty claim?
Rod

Hi Rod,

It is only about a $ 25 part so I would get one to be ready to change it if you find a fault with the old one, they are available from most any large auto parts chain.

Yes you can just remove the sender and check it and if you find anything wrong with it just replace it with a new one. If the float and wire is OK they can be reused to save some work and you will need some tank sealant to put it back on, perhaps you can find a builder near you that has a fresh can if yours is out of date as you will only need about 20 grams to do the plate and screws, be sure to clean off the old tank sealant on the tank and scuff the surface again, one of the benefits of a new sender is not having to clean the old one. It is important to let the tank sealant cure for a day or two is better before you add fuel to the tank.

You may want to recalibrate the fuel quantity in the Dynon as these units vary some from one to the next. This is also simple to do as you have to drain the tank to change the sender just follow the calibration instructions in the Dynon installation manual as you add fuel to the tank when you are done with the sender install.

Good luck.

Best regards,
Vern

 

[Jamie]

Yes, Rod unfortunately the sender is broken. I did the same thing last fall when I removed the sender to repair a leak. If you are really good with a soldering iron you may be able to fix your existing one although my meager skills prevented me from doing so.