hi, now my 06 st is away for winter i need to do some repairs etc, i have the usual dodgy fuel sender and have read lots of threads on it, i get down to a single bar but when i fill it up can never get more than 16 litres or so , i will try cleaning sender if possible but my question is, if fuel level sender is in upper tank how does it know whats in lower tank ? if 27litre capacity then it must be at least 8l in lower tank no? i am going to replace filter in lower tank anyway but confused how it gets an accurate level when all working correctly,
confused on fuel sender
- Thread starter expat-mike
- Start date
The top 7 segments are driven by the float in the upper tank. When that drops low, the last segment starts flashing when the thermistor on the fuel pump bracket is exposed, and the display should show a calculated distance to empty. That should happen after 24L consumed/5L remaining. If you are seeing the low level flash after 16L used then that means the float in the upper tank may be reading low which could be the sensor itself, a bent float arm or a damaged wire. First thing would be to clean the sectors on the potentiometer at the float. After that, the thermistor on the pump bracket (or its wiring) sounds like it could be faulty. There are some basic tests that can be done in the manual pages 22-17 to 19.
Andrew Shadow
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Interpreting the ST1300 Fuel Gauge
Tank Capacities
Normal Indications
Three or More Bars
There is still fuel in the upper tank.
Two Bars
The float in the upper tank has bottomed out. There is still a small amount of fuel remaining in the upper tank.
One Flashing Bar and Estimated Remaining Range
The upper tank and the hose connecting it to the lower tank are empty. The thermistor in the lower tank has been exposed to air and the computer has estimated that there are are 5 liters (1.32 US gallons, 1.10 Imperial gallons) remaining. The fuel consumption display switches to Estimated Remaining Range (ERR).
Tank Capacities
| Tank | Liters | US Gallons | Imperial Gallons | Sensor |
|---|---|---|---|---|
| Upper | 20.80 | 5.50 | 4.57 | Float/sender |
| Lower | 8.20 | 2.17 | 1.81 | Thermistor |
| Total | 29.00 | 7.67 | 6.38 |
Normal Indications
Three or More Bars
There is still fuel in the upper tank.
Two Bars
The float in the upper tank has bottomed out. There is still a small amount of fuel remaining in the upper tank.
One Flashing Bar and Estimated Remaining Range
The upper tank and the hose connecting it to the lower tank are empty. The thermistor in the lower tank has been exposed to air and the computer has estimated that there are are 5 liters (1.32 US gallons, 1.10 Imperial gallons) remaining. The fuel consumption display switches to Estimated Remaining Range (ERR).
thats a great help, thankyou!
thankyou,
Carefully lift the tank, turn it over, and you'll see the mounting point. Remove the screws, carefully lift it out, and take a soft pencil eraser and clean the surface of the gauge.
Check the condition of the O-ring, and replace everything.
Your gauge should read correctly now.
While you've got the tank off, check the condition of the Joint Fuel Tube, that connects the two tanks together.
These get rock hard from heat, and crack, and will dump the entire contents of your fuel tank down on the hot engine etc.
The entire hose should be soft, if the ends are hard, and you have a soft spot in the middle, replace it, as it is getting ready to crack/split on you.
Attachments
so great to have pictures too! will help a lot , and in the second pic is the joiner tube the big thick one? about 1" diameter or so?Carefully lift the tank, turn it over, and you'll see the mounting point. Remove the screws, carefully lift it out, and take a soft pencil eraser and clean the surface of the gauge.
Check the condition of the O-ring, and replace everything.
Your gauge should read correctly now.
While you've got the tank off, check the condition of the Joint Fuel Tube, that connects the two tanks together.
These get rock hard from heat, and crack, and will dump the entire contents of your fuel tank down on the hot engine etc.
The entire hose should be soft, if the ends are hard, and you have a soft spot in the middle, replace it, as it is getting ready to crack/split on you.
Yes