Fuel Gauge/ Sender Issue

[tazdevl20062008]

Ok guys, I posted this in both the Electrical and Fuel System Forums seeing I didn't know exactly which it belonged to. My bike is a 2003 HD Night Train with the EFI (Stock Fuel System and stock tank).

PROBLEM: Fuel Gauge was constantly reading full, even when tank was empty.

DIAGNOSIS: The Fuel Gauge was receiving about 40 ohms from the sender, which per the manual is the correct ohms for a full tank (tank only had about 1 gallon of gas out of a 5 gallon capacity). This indicated the gauge was not the issue and was operating properly.

The gauge needle moves freely from full to empty when the bike is shut on and off, so the needle is not sticking.

I pulled the whole sending unit/ fuel pump assembly out from the tank. Per the manual, the sender should read about 40 ohms at full and 260 ohms when empty. When I checked the sender with a voltmeter, the ohms read as they should. With the arm all the way down simulating an empty tank it read about 200 ohm, and all the way up simulating a full tank the ohms read about 40.

I saw no obvious signs of scratching on the tank walls to indicate the fuel sender's arm was getting hung up on the tank. Also, the float arm moves freely and does not bind at all.

The Gauge got stuck at full after I had filled the tank.

So my question is, why was the gauge stuck at full? Was it a freak thing where the float arm got stuck for some reason? Am I missing something here? There is about 3/8" of the float arm sticking out past the float. Could that little bit be getting hung up, should I trim it? Thanks for the help.

[rtb]

Sometimes, especially if you fill the tank to the very top, the float will stick to the inside middle of the tank. Sometimes hitting a pot-hole will knock it loose and it will follow the gas level again. If you go back into the tank, bend the arm to the left to keep the float away from the middle of the tank.

[LoCo1969]

Just cut off the extra bit of metal sticking out from the float and that'll take car of it.

[tazdevl20062008]

thanks for the response guys. I will cut off the extra metal and bend it a little to see if that helps.

[tazdevl20062008]

Problem fixed. Bent the float arm slightly away from the tank's tunnel and re-installed. Gauge works fine now. I could see in the tank where the float had been rubbing the tunnel for some time now. The float itself had a flat spot on it. You'd thing HD would have thought of this and moved the float a little farther away from the tunnel. Sometimes their engineering baffles the hell out of me.