Fuel gauge/sender issue, Question about fuel gauge/sender issue Options

[lonewolfe]

I've searched ad found several postings on overhauling/repairing fuel senders and have followed those suggestions and continue to have and issue with my fuel gauge. I've tried 3 different fuel senders in my tank and none of them have solved the problem. I get different fuel tank readings with each of the three senders I've tried. One reads just below half full, the second just above half full and the third shows just about 3/4 full. My car has had a full tank of gas when tested. One of the senders is the one that came in the car, one out of another 914 parts car and one I purchased used from EASY in Emeryville. I've cleaned the inside wires and contacts on these used senders as described in the various posts put up on 914world.com, pelicanparts.com and 914club.com and none of these senders have changed readings. I realize the possibility that each of these senders may no longer be good but it seems that many people have had excellent results with repairing their senders after cleaning them out. it seems that if there is a problem with my fuel gauge that it would read the same regardless of which fuel sender I'm using. it seems odd that I get different fuel level readings using different senders. I'd think if the fuel gauge is bad then it would continue to show the same level and not change depending on the sender.

So, I'm asking for your suggestions before going out and spending $100+ on a new fuel sender. Is there something else I should check or do before ordering a new sender? I'm getting pretty frustrated.

Any suggestions will be greatly appreciated!

[timothy_nd28]

Have you tried testing with the sender out of the tank and the shell off? You can physically move the float to the full position, and your gauge should reflect it. Then move the float to the empty position, the guage should also show this as well. If you try this, and it coincides with the gauge, your problem isn't electrical. It's possible the float lost its buoyancy and giving you erroneous readings.
After testing this, and electrically all is well, I would consider buying a new sender. I suppose you could try finding some fuel resistant epoxy, and coat the float assembly. However, you'll need to epoxy something buoyant to the float, to help offset the weight of the epoxy that you just used to seal the float.

[Mike Bellis]

The floats themselves may be bad. They may no longer be buoyant. You may need to open and put in a bucket of gasoline and see if they sink.

If you completely give up (not that you should), Autometer makes a sender that fits perfect in the 914 tank. Bolts right in, but you need an Autometer gauge with it.

[slu234]

I rebuilt mine. The wire inside was broken so I replaced it. It works like a Wheatstone bridge, the resistance changes as the float moves. You really need to put an Ohm meter on it and check the resistance as you move the float up and down to confirm that the resistance is changing over the whole range of the sender. This could help you determine if it is the sender or the gauge wiring.

Also, the wiring to my gauge was pretty flaky giving different readings if I wiggled the wires on the back of the gauge. Check the gauge contacts out, remove, clean, tighten and try again.

Brian

[lonewolfe]

Thanks for all your tips. I've followed what others have done on other threads and opened the sender, cleaned the wires and contacts and still the three I've tried did not work correctly. I believe the floats are probably bad in these old senders. I gave in and ordered a brand new fuel level sender today. That should do the trick! I guess for peace of mind knowing how much fuel I have will make it worth it. My odometer also does not work even though the speedometer works so it's been impossible to gauge my fuel consumption. Looking forward to having the gauge work and not spending any more time on this isssue. There are plenty others to pursue as I get this car straightened out. Thanks again everyone!!!