Low fuel light comes on too soon mod, works.

[Mechaniac]

I was changing out my fuel pump and wanted to see if there was anything I could do to extend the mileage before the low fuel warning light comes on. As built the light would start coming on usually around 85 miles from a fill up. Filling up and comparing amounted needed to fill and published specs revealed there was still a lot of fuel in the tank. I've actually gone 120+ miles before it ran out of fuel and was able to coast into a station that was just ahead. I actually did this recently trying to get the tank as empty as possible for the fuel pump job.

I've seen one person suggest cutting down the fuel level sensor's mounting arm to use the top hole in the bottom bracket hole. But after looking it over closely I decided on a different route and it worked perfectly in my opinion.

After detaching the sensor bracket from the pump frame I noticed that the sensor is soldered to a metal tab that is also wrapped around the bracket leg, a round metal pin, and soldered in a strait up index. Meaning it's sitting on top. I noticed the soldering was light and that if removed might allow the sensor to be rotated 180 degrees downwards thereby placing it about 25 mm lower in the tank but still a good deal above the tank floor. So I got out an air powered cut off wheel tool and carefully removed the soldered ends from the tab to bracket joint. After I couldn't see anymore solder I used two pair of flat bill pliers to twist on them and they popped loose. Interestingly the tab got tight at top and bottom, so it would probably sit at bottom just fine but I got out the soldering gun and redid the joints I had just ground off to ensure it stayed put. I finished the fuel pump change and put it all back together.

Since I had used the bike after running it out of petrol on purpose it had 85 miles on this tank. Upside down it just came to the fuel pump flange without overflowing, but a little did spill during the work. Probably one miles worth was wasted.

On the road with the odometer still at 85 miles the light was off until I reached 102 miles, at which point it seemed like it was starting to glow, the indicator just looked brighter than the rest of the gauge. By 105 it was coming on bright. I was at a station then and filled up just over 3 gallons.

Mission accomplished. No more premature nagging light, now just a "Hey Dummy" light.

[andyvh1959]

Thanks. I too have been bothered by a low fuel light coming on way too early. On my BMWs I know I can get 40 miles on the bike when the fuel light comes on steady. I like that on my BMWs I can easily go 200 miles before I even have to consider getting gas. So when I work on my VN1600 this winter I'll also rework the fuel sender to get something close to 30 miles to go when the fuel light finally comes on. I know my 1600 gets about 38mpg on average, so with a 5.5 gallon tank I'll reset the fuel sender so I can go over 180 miles before I know I REALLY have to get fuel.

One of the many things I like about my BMW 1200 is it makes 110hp, and still gets 48mpg on a regular basis. If I cruise steady on the highway it can exceed 50 mpg. But then, it has lots of electronic engine controls to achieve that along with a 12.0:1 compression ratio to squeeze out a lot of power and efficiency. The VN1600 compression ratio is much lower at 9:1.