Re-post: Fuel float trouble

The fuel level shown on the Volvo Penta engine analyzer which comes from the mechanical float is incorrect. I have read that it is rare for the in-tank float to go bad. Can you advise whether we should change the float sending unit, and if so, the part number? Does it come with a new gasket? Or, if it’s an electrical issue from the sending unit to the engine analyzer, how do we troubleshoot that?

More information would be helpful. Year of boat? Model of boat? Is this a new problem or has it always been inaccurate?
The readout for the tank fuel level on the Volvo gauge is notoriously wrong on many of our boats. There are many existing threads on the problem along with many opinions of why it happens and how to fix it. After wasting time and money replacing the sending unit and attempting to recalibrate the gauge, mine is still way off from the actual quantity remaining. Like most others, I just use the Garmin calculated fuel level as it is extremely accurate.

This is a photo of the sending unit. It is a KUS USA that does come with a Gasket. The model number correlates with the length of the sending unit. It uses a 5 hole mounting pattern. If properly calibrated to the Volvo Penta EVC reading is very accurate. Photo below shows the comparison from the Garmin and the sending unit reading using the EVC with a Properly calibrated sending unit to EVC.
.8 gallon difference.

This is a post I made several years ago about calibrating the sending unit to the EVC.

Hey Brian. Glad you were able to get yours working correctly. I read your post on calibration procedures. Unfortunately I am not an electrician and was not as successful using the published standard calibration procedures. Hope the guy who posted this has better luck than I did.

Thank you all for the assistance. My boat is a 2017 R-29 S LE. The fuel tank holds 145 gallons. We bought the don’t in Sept. and the Volvo gauge and Garmin were in sync for 6 months. Suddenly, the Volvo gauge now reads either 145 gallons or zero gallons. I will review the 2018 discussion threads and then attempt further troubleshooting.

Chris
“Blue Heron”
Charleston, SC