I wanted to share with everyone how I fixed the issue I had with my fuel gauge going into flashing mode with around 3 bars left. First some background, I have a non-ABS 2003 ST1300. The bike had relatively low-miles when I bought it, ~8000. The flashing-gauge issue happened within 100 miles of my purchasing the bike. I looked on this forum and learned the issue could be related to the fuel-sending unit, however, I'm cheap and wanted to try to "fix" it myself.
The first thing I noticed was how loosely the green-wire fit on the bottom fuel tank. I posted about the arcing it was causing and thanks to people on this forum I was able to understand why it was happening. I fixed the loose connector and immediately noticed the behavior of my flashing-gauge changed, from flashing at the 3-bar mark, to flashing at the 2-bar mark. So while the situation had improved, it was still not ideal.
I then decided to check the fuel-sending unit itself. For this I had to remove the tank, which resulted in a about 2 gallons of fuel spilling through a cracked fuel hose (lesson learned was don't lift the tank unless empty and your hoses are not corroded). Once I removed the tank and the fuel-sending unit, I noticed all of the crap on it. The sending unit was full of "gunk". I used a small toothbrush and some mineral spirits to clean it and viola, my flashing-gauge problem is solved. While I had the sending unit out, I tested its resistance following the manual and confirmed it was within spec; 1-6ohm full and 213-219ohm empty.
In summary; make sure the green wire is properly connected. Make sure the fuel-sending unit is not full of gunk, if so, clean it.
I hope this helps.
P.S. Given the fuel hose was corroded and stiff, you can bet your fuel-sending unit o-ring will be as well. So learn from me and order one BEFORE you remove your sending unit
The first thing I noticed was how loosely the green-wire fit on the bottom fuel tank. I posted about the arcing it was causing and thanks to people on this forum I was able to understand why it was happening. I fixed the loose connector and immediately noticed the behavior of my flashing-gauge changed, from flashing at the 3-bar mark, to flashing at the 2-bar mark. So while the situation had improved, it was still not ideal.
I then decided to check the fuel-sending unit itself. For this I had to remove the tank, which resulted in a about 2 gallons of fuel spilling through a cracked fuel hose (lesson learned was don't lift the tank unless empty and your hoses are not corroded). Once I removed the tank and the fuel-sending unit, I noticed all of the crap on it. The sending unit was full of "gunk". I used a small toothbrush and some mineral spirits to clean it and viola, my flashing-gauge problem is solved. While I had the sending unit out, I tested its resistance following the manual and confirmed it was within spec; 1-6ohm full and 213-219ohm empty.
In summary; make sure the green wire is properly connected. Make sure the fuel-sending unit is not full of gunk, if so, clean it.
I hope this helps.
P.S. Given the fuel hose was corroded and stiff, you can bet your fuel-sending unit o-ring will be as well. So learn from me and order one BEFORE you remove your sending unit
